EK-V13XX-TP-001
VT330/VT340
Programmer Reference Manual
Volume 1: Text Programming
USER'S INFORMATION MAP
Installing and Using
The VT330/VT340 Video Terminal
VT330/VT340
Programmer Reference Manual
Install and set
up the terminal
Chapters
2 and 3
Run dual
sessions
Chapters
3 and 8
Use the
Set-Up screens
Chapter
5
Compose
characters
Chapter
6
Define
function keys
Chapter
7
Print data on
a local printer
Chapter
11
Use a modem
Chapter
11
Learn to program
the terminal
Appendix
C
Solve problems
and get service
Chapters
2 and 12
Learn about
character
encoding
Volume 1,
Chapter 2
Find the
code tables
for
character sets
Program the
terminal ' s
text features
Volume 1,
Chapter 2
Volume 1
Chapters
3 to 13
Program the
terminal 's
graphics
features
Volume 2
^-003 {ps^/as
EK-VT3XX-TP-001
VT330/VT340
Programmer Reference Manual
Volume 1: Text Programming
Prepared by Educational Services
of
Digital Equipment Corporation
1st Edition, March 1987
Copyright © 1987 by Digital Equipment Corporation.
All Rights Reserved.
Printed in Taiwan.
The reproduction of this material, in part or whole, is strictly prohibited. For
copy information, contact the Educational Services Department, Digital
Equipment Corporation, Maynard, Massachusetts 01753.
The information in this document is subject to change without notice. Digital
Equipment Corporation assumes no responsibility for any errors that may ap-
pear in this document.
AT&T is a trademark of American Telephone and Telegraph Company.
Tek and Tektronix are trademarks of Tektronix, Inc.
Vadic is a trademark of Racal-Vadic.
The following are trademarks of Digital Equipment Corporation, Maynard,
Massachusetts.
DEC
DECconnect
DECmate
DECnet
DECpage
DECserver
DECsystem-10
DECSYSTEM-20
DECtalk
DECUS
DECwriter
DIBOL
LA12, LA36
LA50, LA75
LA100, LA120
LA210
LN01, LN03
MicroVAX
MicroVMS
PDP
P/OS
Professional
Rainbow
ReGIS
RSTS
LQP02, LQP03 RSX
SSU
UNIBUS
VAX
VMS
VT
VT52, VT100, VT101, VT102
VT125, VT131, VT220, VT240
VT330, VT340
Work Processor
This manual was prepared using DECpage V2.0 software and other in-house
documentation software.
CONTENTS
ABOUT THIS MANUAL • ix
PART 1 INTRODUCTION TO YOUR VT330/VT340
TERMINAL
CHAPTER 1 VT300 FEATURES • 3
The VT330/VT340 Terminal, 3
New Features, 5
General Features, 7
Operating States, 10
Operating Modes, 10
CHAPTER 2 CHARACTER ENCODING • 12
Coding Standards, 13
Characters and Character Sets, 15
Code Table, 15
VT300 Character Sets, 20
Control Characters, 28
Control Functions, 34
Working with 7-Bit and 8-Bit Environments, 40
Display Controls Mode, 41
PART 2 CONTROL FUNCTIONS SENT TO THE HOST
CHAPTER 3 KEYBOARD CODES • 47
Keyboard Codes, 47
Special Cases, 58
CONTENTS Hi
PART 3 CONTROL FUNCTIONS RECEIVED FROM THE
HOST
CHAPTER 4 EMULATING VT SERIES TERMINALS • 65
Level 1 (VT100 mode), 66
Level 3 (VT300 mode), 66
All Levels, 66
Selecting an Operating Level, 68
Sending Cl Controls to the Host, 69
National Replacement Character Set Mode (DECNRCM), 70
CHAPTER 5 USING CHARACTER SETS • 71
Selecting Character Sets (SCS), 72
Soft Character Sets, 82
CHAPTER 6 PAGE MEMORY • 102
What is Page Memory?, 103
Controlling the Page Format, 106
Moving to Another Page, 109
Summary, 111
CHAPTER 7 SETTING VISUAL CHARACTER AND LINE
ATTRIBUTES • 114
Setting Visual Character Attributes, 114
Setting Line Attributes, 116
Summary, 117
CHAPTER 8 EDITING AND CHARACTER PROTECTION • 118
Editing, 119
Character Protection, 126
Independent Protection. 126
Visual Attribute Protection, 129
Summary, 131
CHAPTER 9 LOCAL EDITING • 134
How Local Editing Works, 135
Selecting Edit Mode, 136
Defining the Size of the Character Block, 137
Selecting the Characters to Send. 141
End-of-Block and Unused Space Characters, 144
iv CONTENTS
Sending Edited Data to the Host, 148
Block Transmission Examples, 149
Character Sets and Block Transmission, 153
Summary, 156
CHAPTER 10 CURSOR MOVEMENT AND PANNING • 159
The Cursor, 161
Moving the Cursor on the Current Page. 161
Panning, 163
Cursor Coupling, 164
Summary, 167
CHAPTER 11 KEYBOARD, PRINTING, AND DISPLAY
COMMANDS • 169
Keyboard Control Functions, 170
User-Defined Keys (DECUDK), 175
Printer Port Control Functions, 181
Printing Functions, 182
Printing Visual Attributes, 185
Screen Display Control Functions, 186
Summary, 190
CHAPTER 12 VT300 REPORTS • 195
Device Attributes (DA), 196
Terminal Identification (DECID), 200
Device Status Reports (DSR), 201
Terminal State Reports, 205
Presentation State Reports, 209
Mode Settings, 218
Control Function Settings, 225
Saving and Restoring the Cursor State, 229
Window Reports, 230
User-Preferred Supplemental Set, 231
Summary, 233
CHAPTER 13 RESETTING THE TERMINAL • 241
Soft Terminal Reset, 242
Hard Terminal Reset, 244
Tab Clear, 245
Summary, 241
CONTENTS v
PART 4 DUAL SESSIONS
CHAPTER 14 SESSION MANAGEMENT • 249
Dual Sessions, 249
Two Ways to Manage Sessions, 250
Session Resources, 252
Multiple System Communications (MSC), 254
Session Support Utility, 254
Selecting Sessions (MSC or SSU Software), 255
APPENDIX A VT52 MODE CONTROL CODES • 257
Entering VT52 Mode, 257
Exiting VT52 Mode, 258
APPENDIX B COMMUNICATIONS • 259
Character Format, 260
Making Connections, 260
Communicating with Non-Digital Systems. 261
VT300 Communication Ports, 265
Modems, 271
Communications Set-Up Screen, 272
Flow Control Features, 272
Character Format Features, 274
Modem Features, 275
Break, 279
Standards and Certification, 280
GLOSSARY • 285
INDEX OF CONTROL FUNCTIONS • 303
GENERAL INDEX • 321
FIGURES
1-1 VT330/VT340 Video Display Terminal, 4
2-1 7-Bit ASCII Code Table, 1 7
2-2 7-Bit Code, 17
2-3 8-Bit Code Table, 19
2-4 8-Bit Code, 19
vi CONTENTS
2-5 DEC Multinational Character Set, 21
2-6 ISO Latin Nr 1 Supplemental Character Set, 23
2-7 DEC Special Graphic Character Set, 26
2-8 DEC Technical Character Set, 27
2-9 Display Controls Font, 42
3-1 Four Key Groups (North American/U.K. Keyboard). 48
3-2 Standard Key with a Data Processing Character, 49
5-1 Character Set Selection, 73
5-2 Designating and Mapping Character Sets in VT100 Mode, 76
5-3 Designating and Mapping Character Sets in VT300 Mode, 77
5-4 Character Cell Sizes for 80- and 132-Column Fonts, 83
5-5 Character Body Sizes for 80- and 132-Column Fonts, 84
5-6 Example of an Uppercase D in an 80-Column Font, 85
5-7 Sixel-to-ASCII Conversion, 89
6-1 A Page in Page Memory, 103
6-2 Page Sizes for a Single Session, 104
6-3 Page Sizes for Dual Sessions, 105
9-1 Sending Data in Edit Mode, 150
10-1 The Difference Between Scrolling and Panning, 160
14-1 Typical MSC Environments, 251
14-2 Typical SSU Environment, 252
TABLES
2-1 National Replacement Character Sets, 25
2-2 CO (7-Bit) Control Characters Recognized, 28
2-3 CI (8-Bit) Control Characters Recognized, 31
2-4 8-Bit Control Characters and Their 7-Bit Equivalents, 32
3-1 Codes Sent by Editing Keys, 51
3-2 Codes Sent by Arrow Keys, 52
3-3 Codes Sent by Numeric Keypad Keys, 53
3-4 Codes Sent by the Top-Row Function Keys, 55
3-5 Keys Used to Send 7-Bit Control Characters, 57
3-6 Keys Affected by Local Editing Mode, 58
4-1 Control Functions Ignored in Level 1 (VT100 mode), 67
5-1 Character Sets Available, 72
5-2 Designating Character Sets, 74
5-3 Mapping Character Sets with Locking Shifts, 78
CONTENTS vii
5-4 Guidelines for Designing Soft Characters, 83
5-5 Converting Binary Code to an ASCII Character, 87
5-6 DECDLD Parameter Characters, 92
5-7 Valid DECDLD Parameter Combinations, 96
6-1 Page Format Sequences, 112
6-2 Sequences for Moving Through Page Memory, 113
7-1 Visual Character Attribute Values, 115
7-2 Character and Line Attribute Sequences, 117
8-1 Control Functions Affected by Character Protection, 119
8-2 Editing Sequences, 131
8-3 Character Protection Sequences, 133
9-1 Defining the Character Block Size for Transmission, 138
9-2 Selecting Character Fields for Transmission, 141
9-3 Local Editing Sequences, 156
10-1 Cursor Movement and Panning Sequences, 167
11-1 Keyboard Control Sequences. 191
11-2 Programming UDKs, 192
11-3 Printing Control Sequences, 193
11-4 Screen Display Control Sequences, 194
12-1 Alias Primary DA Responses from the VT300, 199
12-2 ANSI Modes for DECRQM, DECRPM. SM and RM, 220
12-3 DEC Private Modes for DECRQM. DECRPM, SM and RM, 220
12-4 Control Functions for DECRQSS REquests, 226
12-5 Sequences for VT300 Reports, 233
13-1 Soft Terminal Reset (DECSTR) States. 242
13-2 VT300 Reset Sequences, 246
A-l VT52 Escape Sequences, 258
B-l Cables to Terminal Servers, Modems, and Statistical Multiplexers, 263
B-2 Cables to Digital Printers
B-3 EIA Interface Signals for the 25-Pin RS232 Connector, 266
B-4 Common Speed Settings for Modems, 269
B-5 Worldwide Modem Protocols, 272
viii CONTENTS
ABOUT THIS MANUAL
This reference manual is for people with a general knowledge of computer pro-
gramming. If you are a programmer, this manual provides the information you
need to program the text features of your VT330 or VT340 terminal. Volume 2
covers graphics programming features. The VT330 is a text and monochrome
graphics terminal. The VT340 is a text and color graphics terminal.
This manual is part of the VT300 user documentation package. Each manual in
the package is for a certain audience.
• Installing and Using the VT330/VT340 Video Terminal
For the installer and general user
• VT330/VT340 Programmer Reference Manual
Programmers writing applications for the VT330/VT340
Volume 1 Text applications
Volume 2 Graphics applications
Pocket Guide Summary of volumes 1 and 2
ORGANIZATION
The manual is divided into four parts.
Part 1, Introduction to Your VT300 Terminal
covers the information you need to know before you begin programming the
terminal.
• Chapter 1, "VT300 Features," provides an overview of the terminal.
The chapter briefly describes the terminal's major features and oper-
ating modes.
IX
• Chapter 2, "Character Encoding," describes the character-encoding
concepts used when the VT300 operates as a text terminal. The
chapter also describes the terminal's character sets, and control
function format.
Part 2, Control Functions Sent to the Host
covers the codes sent from the keyboard.
• Chapter 3, "Keyboard Codes," describes the characters and control
functions that the terminal sends to the host.
Part 3, Control Functions Received from the Host
covers all the control functions you can use to program the terminal.
• Chapter 4, "Emulating VT Series Terminals," describes the control
functions used to emulate Digital's other VT series terminals.
• Chapter 5, "Using Character Sets," describes the control functions
used to select the terminal's built-in character sets and your own
soft character sets.
• Chapter 6, "Page Memory," describes the control functions used to
format and move through the terminal's page memory.
• Chapter 7, "Setting Visual Character and Line Attributes," de-
scribes the control functions used to highlight text, such as holding
and underlining.
• Chapter 8, "Editing and Character Protection," describes the control
functions used to edit or protect characters in the terminal's page
memory.
• Chapter 9, "Local Editing," describes the control functions that let
the terminal perform local editing tasks. To use this feature, your
host system must support local editing.
• Chapter 10, "Cursor Movement and Panning," describes the control
functions used to move the cursor and pan through data in page
memory.
• Chapter 11, "Keyboard, Printing, and Display Commands," de-
scribes the control functions used to program the terminal's key-
board, printer port, and display screen.
x ABOUT THIS MANUAL
• Chapter 12, "VT300 Reports," describes the control functions used
to request reports on the operating state of the terminal. The chap-
ter also describes the format of the reports sent by the terminal,
and the control functions use to restore the terminal to a previous
state.
• Chapter 13, "Resetting the Terminal," describes the control func-
tions used to reset the terminal's operating features to factory-
default or saved settings.
Part 4, Dual Sessions
describes two methods for managing sessions on the VT300.
• Chapter 14, "Session Management," describes the commands used
to control the terminal's dual-session capability. You can use
Digital's SSU software to run dual sessions over a single communi-
cation line.
Appendix A, "VT52 Mode Control Codes," describes control functions used
when the terminal is in VT52 mode.
Appendix B, "Communication," describes how the terminal communicates with
the host system and local devices, such as modems and printers. The appendix
also describes how to connect to non-Digital systems and provides cabling
information.
Appendix C, "Compatibility with Other Digital Terminals," compares the
VT330 and VT340 terminals to other VT series terminals.
CONVENTIONS USED IN THIS MANUAL
• This manual uses the term VT300 when describing features common
to the VT330 and VT340 terminals.
• Notes and programming tips appear throughout this manual.
— Notes provide general operating information.
— Programming tips provide helpful suggestions to consider when
writing applications.
• Set-up features and keyboard keys appear in bold type.
Examples
Press the Return key.
ABOUT THIS MANUAL xi
Use the Clear Communications feature in the Set-Up Directory
screen.
Characters used in control functions appear in bold type. Below each
character is a column/row number that indicates the character's po-
sition in a standard code table.
Example
ESC #6 <— Control function
1/11 2/3 3/6 <— Column/row numbers
Glossary entries appear in italics when first used in text.
Example
The VT300 stores information in its page memory.
xii ABOUT THIS MANUAL
PART 1
INTRODUCTION TO YOUR
VT330/VT340 TERMINAL
VT300 FEATURES
1
The VT330/VT340 Terminal, 3
New Features, 5
Dual Sessions, 5
User Windows, 5
Page Memory, 6
Local Editing, 6
ROM Cartridge Firmware, 7
General Features, 7
Set-Up, 7
Display Features, 7
Text Features, 8
Character Sets, 9
Communication Features, 9
Operating States, 10
On-Line, 10
Local, 10
Operating Modes, 10
The VT330/VT340 Terminal
This chapter provides an overview of the VT330 and VT340 video terminals.
The chapter briefly describes the major features and operating modes of each
terminal. Each section tells you where to look in the manual for more informa-
tion on that feature.
The VT330 is a monochrome text and graphics terminal. The VT340 is a text
and color graphics terminal. Each terminal has two major components, a
monitor/terminal unit and keyboard. The monitor has a tilt-swivel base. See
Installing and Using the VT330/VT340 Video Terminal for a description of
these components.
This manual covers the programming information you need to use the text fea-
tures for both terminals. Each terminal uses control functions specified by the
American National Standards Institute (ANSI) and the International
Organization for Standardization (ISO). Volume 2 covers the graphics features
for the VT330 and VT340.
This manual uses the term VT300 when describing features common to all both
models. The manual only refers to a specific model when a feature is unique to
that model. Most text features work on both VT300 models.
Figure 1-1 shows a typical VT300 terminal. The next section describes some of
the more important new features of the VT300.
Figure 1-1 VT330/VT340 Video Display Terminal
4 VT300 FEATURES
NEW FEATURES
The VT300 is compatible with Digital's VT220 terminal and offers major new
features such as dual sessions, user windows, added page memory, and local
editing.
Dual Sessions
When you electronically connect to a host system from your terminal, you start
an interactive session. The VT300 lets you run two sessions at the same time.
That is, you can connect to two different jobs on your system. If you connect
your VT300 to two systems, you can log in to both systems and run those
sessions at the same time. If you connect your VT300 to a terminal server that
supports several systems, you can run two sessions, each on a different system.
The dual sessions feature gives you two terminals in one. The VT300 maintains
the two sessions separately. You can easily switch back and forth between the
two sessions by pressing a single key.
The VT300 has two different methods for managing dual sessions, multiple sys-
tem communications (MSC) and Digital's Session Support Utility.
MSC Uses two separate communication lines to maintain two
sessions at the same.
SSU software Uses one communication line and Digital's proprietary SSU
software protocol to maintain two sessions at the same
time.
You can select different operating features for each session. For example, you
can use different set-up selections, page memory format, and user-defined keys.
For more information on session management, see Chapter 14.
User Windows
The VT300 lets you view data from two sessions at the same time. To view
data from two sessions, you divide the screen into two windows.
By default, each session you open with a VT300 terminal uses the complete
screen. This means the terminal can only display data from one session at a
time. To divide the screen into two windows, you press a sequence of keys.
Each window is assigned to a session. Information from one session appears in
one half of the screen, information from the second session appears in the
other half.
VT300 FEATURES 5
You can divide the screen vertically or horizontally. When you divide the screen
vertically, a border appears down the middle of the screen from line 1 to line
24. When you divide the screen horizontally, a border appears across the mid-
dle of the screen from column 1 to the last column.
For more information on user windows, see Chapter 8 of Installing and Using
the VT330/VT340 Video Terminal.
Page Memory
The VT300 has a multiple-page display memory. This feature lets the terminal
store more text than appears on the screen. For example, when you use dual
sessions the terminal can store up to three screen areas of text (three 24-line
pages) for each session.
You can select different page sizes. The page sizes available depend on whether
you are running dual sessions or a single session.
Dual Sessions
3 pages of 24 lines x 80 or 132 columns
2 pages of 36 lines x 80 or 132 columns
1 page of 72 lines x 80 or 132 columns
Singi
e Session
6 pages of 24 lines x 80 or 132 columns
4 pages of 32 lines x 80 or 132 columns
2 pages of 72 lines x 80 or 132 columns
1 page of 144 lines x 80 or 132 columns
A page is a section of the terminal's page memory. Each page has left, right,
top and bottom margins. You can define the size and layout of a page by using
set-up features or control functions.
For more information on page memory, see Chapter 6.
Local Editing
The VT300 lets you perform local editing, also known as block mode editing.
However, local editing requires host software support.
Local editing lets you edit and store data in the terminal, so the host system is
free to perform other tasks. When you finish editing, you can send the edited
data to the host in a block.
VT300 FEATURES
Local editing mode is compatible with the local editing feature on Digital's
VT131 terminal, with some added functions.
For more information on local editing, see Chapter 9.
ROM Cartridge Firmware
All firmware for the VT300 is on a ROM cartridge, installed at the rear of the
terminal. This cartridge must be installed for the terminal to operate. The ter-
minal comes with the ROM cartridge already installed.
GENERAL FEATURES
This section describes the general operating and communication features of the
VT300. You can set many of these features from the keyboard, using set-up.
Set-Up
Set-up is a series of display screens. Each screen lists a group of features, such
as communications or printing.
You can use set-up screens to examine and change the current settings for
features. For example, you can select the keyclick feature, transmit or receive
speeds, page size, and type of session management.
The VT300 set-up feature is similar to the VT200 set-up feature. However, the
VT300 set-up screens have an enhanced format that provides more information
and is easier to use. Installing and Using the VT330/VT34O Video Terminal
describes the set-up screens in detail.
Display Features
The VT300 screen has the following basic features.
Monitor VT330: 359 mm (14 inch), flat screen monitor
VT340: 333 mm (13 inch), conventional color monitor
Display area 25 lines x 80 or 132 columns
800 (horizontal) x 500 (vertical) pixels
Status line on the 25th display line
Character size For 80 columns:
9 x 12 pixel body in 10 x 20 character cell
VT300 FEATURES 7
For 132 columns:
5 x 12 pixel body in 6 x 20 character cell
Bitmap
VT330: 2 plane (permits 4 shades of gray, out
of a possible 64)
VT340: 4 plane (permits 16 shades or colors,
out of a possible 4096)
Scrolling
Horizontal split-screen scrolling on any line boundary
(same as VT100)
Text Features
The VT300 provides a variety of text and editing features.
Character sets
(See next
section.)
Top-row
function keys
Editing
functions
Visual
character
attributes
Line
attributes
Character
protection
styles
Control
functions
5 sets of 94 characters each
1 set of 96 characters
Down-line-loadable character set (94 or 96 characters)
5 local function keys
15 user-definable keys
All VT200 editing functions
Erasure mode
Local editing
Normal, bold, underline, blinking,
reverse video, and invisible characters
Single-width/single-height lines
Double-width/single-height lines
Double-width/double-height lines
Independent (not based on visual character
attributes)
Visual attribute (VT131 style)
7-bit and 8-bit control characters
ANSI control functions
DEC private control functions
Ability to display control functions
8 VT300 FEATURES
Character Sets
The VT300 has the following built-in character sets.
ASCII
DEC Supplemental Graphic
ISO Latin Alphabet Nr 1 supplemental graphic
12 National replacement character sets (NRCs)
DEC Technical
DEC Special Graphic (VT100 line drawing)
You can also design a soft character set and load it from the host system into
the terminal.
Together, the ASCII and DEC Supplemental Graphic sets make up the DEC
Multinational character set. When you turn on or reset the terminal, the
VT300 automatically uses the DEC Multinational set. The ASCII and ISO
Latin-1 supplemental sets make up the ISO Latin-1 character set.
Chapter 2 describes the VT300 character sets. Chapter 5 describes how to se-
lect and use different character sets.
Communication Features
The VT300 provides the following features for communicating with the host
system.
Character format 7-bit or 8-bit
Baud rate Asynchronous communication speeds up to
19. 2K bits per second
Connectors Two DEC-423 host ports, allowing longer
distances between the terminal and host(s)
One RS232-C host port, with a 25-pin
D-subminiature connector for a host or
external modem
One DEC-423 printer port
One 7-pin micro-DIN connector for a mouse or
graphic tablet
VT300 FEATURES 9
OPERATING STATES
The VT300 has two major operating states. You select the operating state in
set-up.
On-line
Local
On-Line
The on-line state lets the terminal communicate with a host system. The termi-
nal sends data entered at the keyboard to the host. The terminal displays data
received from the host on the screen.
Local
The local state lets you place the host system on hold. Data entered at the
keyboard is sent to the screen, but not to the host. The terminal stores data
received from the host, until you put the terminal back on-line.
OPERATING MODES
The VT300 has four major operating modes for text operations. You can select
each mode from the keyboard via set-up, or from the host via control codes.
The VT300 uses standard ANSI functions in all operating modes, except VT52
mode.
VT300 mode, 7-bit controls (default)
VT300 mode, 8-bit controls
VT100 mode
VT52 mode
VT300 mode, 7-bit controls is the default operating mode. This mode provides
the full range of VT300 capabilities, using 8-bit characters and 7-bit control
characters. All character sets are available. This mode provides full compatibil-
ity with Digital's VT200 series terminals. Digital recommends this mode for
most applications.
VT300 mode, 8-bit controls provides the full range of VT300 capabilities, using
8-bit characters and 8-bit control characters. All character sets are available,
and the terminal recognizes both 7-bit and 8-bit controls. This mode will run
VT200 applications that use 8-bit control characters. The terminal operates
most efficiently in this mode, but many systems and applications do not yet
support 8-bit operation.
10 VT300 FEATURES
VT100 mode provides full compatibility with Digital's VT102 terminal. This
mode restricts the terminal to a 7-bit environment. The keyboard is restricted
to VT100 keys, and the only available character sets are ASCII, national re-
placement characters, and DEC Special Graphic. You can use this mode with
applications that require strict VT100 compatibility.
VT52 mode provides full compatibility with Digital's VT52 terminal. This mode
only uses Digital's private control functions, not standard ANSI functions. You
use this mode with applications written for the VT52.
Chapter 2 describes the format for 7-bit and 8-bit character codes. Chapter 4
describes how the VT300 can emulate other VT series terminals.
VT300 FEATURES 11
2
CHARACTER ENCODING
Coding Standards, 13
Characters and Character Sets, 15
Code Table, 15
7-Bit ASCII Code Table, 16
8-Bit Code Table, 18
VT300 Character Sets, 20
DEC Supplemental Graphic Character Set, 21
ISO Latin Alphabet Nr 1 Supplemental Graphic Character Set, 23
National Replacement Character Sets (NRC Sets), 24
DEC Special Graphic Character Set, 26
DEC Technical Character Set, 27
Down-Line Loadable (Soft) Character Set, 28
Control Characters, 28
Control Functions, 34
Sequence Format, 35
Escape Sequences, 35
Control Sequences, 36
Device Control Strings, 37
Using Control Character in Sequences, 39
7-Bit Code Extension Technique, 39
Working with 7-Bit and 8-Bit Environments, 40
Conventions for Codes Received by the Terminal, 40
Conventions for Codes Sent by the Terminal, 41
Display Controls Mode, 41
12
The VT300 uses a communication line to exchange information with a host sys-
tem. The terminal and the host do not send data in the form you see on your
screen. They must encode the information first. They also must be able to de-
code the information received from each other.
This chapter describes the character-encoding system that the VT300 uses for
text. The terminal uses a different system for graphics. You must have a basic
understanding of the character-encoding system described in this chapter before
you use the control functions in the rest of this manual.
The chapter also describes the VT300 character sets and the format for send-
ing control functions to the terminal. You can select character sets for different
countries or for special uses, such as technical characters. You use control func-
tions to make the terminal perform special functions, such as editing or print-
ing.
CODING STANDARDS
All terminals and computers encode information as binary digits, or bits. Older
systems use 7 bits to encode each character. Newer systems such as the
VT300 use 8 bits, which provide more codes. The newer systems can also use
the 7-bit codes.
The VT300 uses an 8-bit character-encoding system and a 7-bit code extension
technique. The "7-Bit Code Extension Technique" section in this chapter ex-
plains what 7-bit code extensions are.
The American National Standards Institute (ANSI) and International
Organization for Standardization (ISO) specify standards for character encoding
in the information processing industry. The VT300 terminal is compatible with
the following ANSI and ISO standards.
Standard Description
dpANS X3. 134.1 8-Bit ASCII structure and rules
dpANS X3. 134.2 Code for information interchange of 7-bit
and 8-bit ASCII supplemental multilingual
graphic character set
ANSI X3.4 — 1977 American Standard Code for Information
Interchange (ASCII)
CHARACTER ENCODING 13
Standard
ANSI X3.41 — 1974
ANSI X3.32- 1973
ANSI X3.64 — 1979
ISO 646 — 1977
ISO 2022
ISO 6429
ISO 8859-1
ISBN 2-12-953907-0
Description
Code Extension Techniques for Use with
the 7-Bit Coded Character Set of
American National Code Information
Interchange
Graphic Representation of the
Control Characters of American
National Code for Information
Interchange
Additional Controls for Use with
American National Standard for
Information Interchange
7-Bit Coded Character Set for
Information Processing Interchange
7-Bit and 8-Bit Coded Character
Sets — Code Extension Techniques
Additional Control Functions for
Character Imaging Devices
8-Bit single byte code graphic character
sets-Part 1: Latin Alphabet Nr 1
ISO international register of character
sets used with escape sequences
You can order ANSI and ISO standards from the following sources.
ANSI Standards
Sales Department
American National Standards Institute
1430 Broadway
New York, NY 10018
ISO Standards
CCITT
UN Book Store
United Nations Building
New York, NY 10017
14 CHARACTER ENCODING
CHARACTERS AND CHARACTER SETS
In Digital's computing environment, a character is a symbol represented by an
8-bit binary code. These symbols include letters, digits, and punctuation marks,
as well as other symbols used to organize, control, or represent data.
Here are a few examples of characters and their corresponding 8-bit codes.
Character
Code
A
}
CSI
01000001
01111101
10011011
There are two types of computing environments, 7-bit and 8-bit. In a 7-bit envi-
ronment, only the last 7 bits of the character code define the character. In an
8-bit environment, all 8 bits define the character.
The A character above is defined in a 7-bit or 8-bit environment, because the
eighth bit of the code is 0. The 8-bit form of the CSI character is defined only
in a 8-bit environment, because its eighth bit is 1.
A coded character set is a group of characters that conform to certain rules
and standards. These standards are set by organizations such ANSI and ISO.
Each character in a character set is represented by a different combination of 8
bits.
CODE TABLE
A code table is a convenient way to show all the characters in a character set
with their codes. Most standard character sets put similar characters into
groups, so they have similar codes. A code table lets you see groups of charac-
ters and their relative codes clearly.
There are two basic types of characters, graphic characters and control charac-
ters. These two character types are defined by ANSI and ISO standards. The
VT300 processes received characters based on these two character types.
Graphic characters are characters you can display. Graphic characters include
letters, numbers, punctuation marks, and any other characters you can display.
Control characters are characters you do not usually display. They make the
terminal or host system perform specific functions in data communications and
text processing.
CHARACTER ENCODING 15
NOTE: You can display control characters on the screen, to help you debug
your applications. To display control characters, use the Control
Representation Mode feature in the Display Set-Up screen. See the "Display
Controls" section at the end of this chapter.
This section describes the format for 7-bit and 8-bit code tables.
7-Bit ASCII Code Table
Figure 2-1 is the 7-bit ASCII code table. The table has 128 character codes,
arranged in 8 columns and 16 rows.
Every character in a row uses the same binary code for its four least signifi-
cant bits (Figure 2-2). This value appears at the left of each row. For example,
every character in row uses the binary code 0000 for its four least significant
bits.
Every character in a column uses the same binary code for its three most sig-
nificant bits. This value appears at the top of each column. For example, every
character in column uses the binary code 000 for its three most significant
bits
The ASCII table also shows the octal, decimal, and hexadecimal code for each
character. Different programmers may prefer using octal, decimal, or hexade-
cimal codes for different purposes.
This manual refers to characters by their position in the table. For example,
the character H is at 4/8 (column 4, row 8). You can use the column/row num-
ber to find a character and its codes in the table. For example
ESC # 6
1/11 2/3 3/6
means
The ESC character is at column 1, row 11.
The ft character is at column 2, row 3.
The 6 character is at column 3, row 6.
The ASCII graphic characters are in positions 2/1 through 7/14 of the ASCII
table. ASCII graphic characters include all American and English alphanumeric
characters, plus punctuation marks and various text symbols. Examples are C,
n, ", !, +, and $. (The British pound sign is not an ASCII graphic character.)
16 CHARACTER ENCODING
COLUMN
1
2
3
4
5
6
7
ROW
hfi BITS
67
66
bS
b4 S3 b? bl
1
NUL
o
DLE
zo
10
SP
40
32
20
60
48
30
@
100
64
p
120
30
50
x
140
96
60
P
112
70
1
1
SOH
;
DC1
IXONI
21
17
!
41
33
21
1
49
31
A
65
Q
121
81
51
a
141
61
q
161
113
71
2
10
STX
2
2
2
DC 2
18
12
M
42
34
22
2
62
50
32
B
102
66
42
R
B2
52
b
9S
62
r
114
72
3
1 1
ETX
3
3
3
DC 3
(XOFFI
23
19
13
#
43
35
3
63
51
33
C
103
67
43
S
123
B3
53
c
143
99
63
s
lb J
•15
73
4
D 1
EOT
4
DC4
20
$
36
24
4
64
52
34
D
104
T
124
B4
54
d
144
100
64
t
164
116
74
5
10 1
ENQ
5
5
5
NAK
25
21
15
%
25
5
65
53
35
E
105
69
45
U
125
85
5b
e
101
65
u
:G5
75
6
110
ACK
■5
S
5
SYN
26
22
&
40
38
26
6
66
54
36
F
106
70
46
V
126
86
56
f
146
102
66
V
166
11B
76
7
111
BEL
ETB
23
17
'
47
39
27
7
67
55
37
G
10/
w
127
e?
57
g
147
103
67
w
167
119
8
1
BS
10
CAN
30
24
Ifi
(
50
40
2B
8
70
56
3a
H
110
72
X
130
as
58
h
150
104
68
X
170
120
78
9
10 1
HT
9
S3
EM
25
19
)
51
41
29
9
71
57
39
1
111
73
49
Y
131
89
59
i
151
105
69
y
171
121
79
10
10 10
LF
13
10
SUB
32
26
1A
#
52
42
2A
72
58
3A
J
112
z
132
90
Sit
J
152
106
6A
z
172
122
7A
11
lO'i
VT
13
B
ESC
33
27
IB
+
53
43
2B
;
73
59
3B
K
113
75
46
[
133
91
k
153
107
6B
{
173
123
7B
12
110
FF
14
12
C
FS
31
28
1C
,
44
2C
<
74
60
3C
L
76
\
134
92
SC
1
154
103
60
1
174
124
7C
13
110 1
CR
15
13
D
GS
35
29
ID
"
55
45
2D
-
75
61
3D
M
115
77
4D
]
135
93
5D
m
155
109
6D
>
175
125
7D
14
1110
SO
(6
F
RS
3G
30
IE
56
46
2E
>
76
62
3E
N
116
78
4E
A
136
94
5E
n
156
110
6E
""
126
7E
15
1111
SI
17
15
US
37
31
1F
/
57
2F
?
77
63
3F
117
4F
-
137
95
5F
157
6F
DEL
177
127
7F
GL CODES
"(ASCII GRAPHIC )
KEY
CHARACTEf
ESC
33
27
IB
OCTAL
DECIMA
Figure 2-1 7-Bit ASCII Code Table
BIT
BIT'
BIT
BIT
BIT
BIT
BIT
7
6
5
4
3
2
1
4 ►♦«
1 3 MOST
SIGNIFICANT BITS
4 LEAST
SIGNIFICANT BITS
(DECIMAL VALUE IS
COLUMN IN
CODE TABLE)
(DECIMAL VALUE
IS ROW IN
CODE TAB LEI
Figure 2-2 7-Bit Code
CHARACTER ENCODING 17
The ASCII control characters are in positions 0/0 through 1/15 (columns and
1) of the ASCII table. The SP character (2/0) may act as a graphic space char-
acter or a control character, depending on the context. DEL (7/15) is always a
control character.
ANSI and ISO standards define control character codes and their functions.
These standards also define the mnemonic used to represent each control char-
acter in a code table. Here are some examples of ASCII control characters with
their mnemonics.
ASCII Control Character Mnemonic (Appears in Code Table)
Carriage return
CR
Form feed
FF
Cancel
CAN
8-Bit Code Table
Figure 2-3 shows the format for an 8-bit code table. It has the same number of
rows as the 7-bit table, but twice as many columns and character code posi-
tions.
Each character in a row of the 8-bit table uses the same binary code for its
four least significant bits (Figure 2-4). Each character in a column uses the
same binary code for its four most significant bits.
The codes on the left half of the 8-bit table (columns through 7) work like the
codes in the 7-bit table. You can use these codes in a 7-bit or 8-bit environ-
ment. The eighth bit of these codes is 0.
The codes on the right half of the table (columns 8 through 15) have an eighth
bit of 1. You can only use these codes in an 8-bit environment.
The 8-bit code table has two sets of control characters, CO (control zero) and
CI (control one). The VT300 uses the ANSI definitions for the functions of CO
and CI controls. The CO controls are in columns and 1. The CO controls are
the same as the ASCII control characters in the 7-bit table. You can use CO
controls in a 7-bit environment.
The CI controls are in columns 8 and 9. They perform different functions than
the CO controls. You can only use CI controls directly in an 8-bit environment.
You can select CI codes indirectly in a 7-bit environment. The "7-Bit Code
Extension Technique" section in this chapter explains how to select CI con-
trols indirectly. Some CI code positions are blank, because their functions are
not yet standardized.
18 CHARACTER ENCODING
COLUMN
ROW V
00
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
00
MJL
OLE
SP
DCS
01
SOH
DC1
PU1
02
STX
DC2
PU2
03
ETX
DC3
STS
04
EOT
OC4
IND
CCH
OS
ENQ
NAK
NEL
MW
06
ACK
SYN
SSA
SPA
07
BEL
ETB
ESA
EPA
08
as
CAN
HTS
09
HT
EM
HTJ
10
LF
SUB
VTS
11
VT
ESC
PLD
CSI
12
FF
FS
PLU
ST
13
CB
GS
Rl
OSC
14
SO
RS
SS2
PM
15
SI
LIS
DEL
SS3
APC
*C1 CODE^I"
-7-BIT CODE TABLE-
MA-Q892-83
Figure 2-3 8-Bit Code Table
BIT
8
BIT
7
BIT
6
BIT
5
BIT
4
BIT
3
BIT
2
BIT
1
I,
r 1 -
.1
r"
1
4 MOST
SIGNIFICANT BITS
4 LEAST
SIGNIFICANT BITS
(DECIMAL VALUE IS
COLUMN IN
CODE TAB LEI
(DECIMAL VALUE
IS ROW IN
CODE TABLE)
Figure 2-4 8-Bit Code
CHARACTER ENCODING 19
NOTE: The VT300 does not recognize all CO and Cl codes. Tables 2-2 and 2-3
list the codes the terminal recognizes. The terminal generally ignores all other
control codes.
The table also has two sets of graphic characters, GL (graphic left) and GR
(graphic right). There are 94 GL codes in positions 2/1 through 7/14. You can
use GL codes in 7-bit or 8-bit environments.
There are 96 GR codes in positions 10/0 through 15/15. Some 8-bit character
sets only use 94 of these GR codes. You can use GR codes only in an 8-bit
environment.
Together, the GL and GR sets make up the terminal's in-use table. The in-use
table contains the graphic characters the terminal can currently use. Before the
terminal can display and send characters from a character set, the set must be
mapped into the in-use table. Chapter 5 describes the in-use table in detail.
VT300 CHARACTER SETS
The VT300 provides the following built-in character sets.
ASCII
DEC Supplemental Graphic
ISO Latin Alphabet Nr 1 supplemental graphic
12 national replacement character sets (NRCs)
DEC Special Graphic
DEC Technical
You can also design and load a soft character set into the terminal.
Down-line-loadable (soft) set
All the VT300 character sets contain graphic and control characters. The func-
tion of control characters never change, no matter what character set you use.
The terminal always interprets CO and Cl control codes as defined by ANSI.
The terminal stores the codes for graphic characters in GL and GR tables.
Selecting a new character set changes the characters associated with the GL or
GR codes. When you turn on or reset the terminal, you automatically select the
following character sets.
ASCII in GL
DEC Supplemental (or ISO Latin-1 supplemental) graphic in GR
Together, the ASCII and DEC Supplemental Graphic sets are known as the
DEC Multinational character set.
20 CHARACTER ENCODING
DEC Supplemental Graphic Character Set
This 8-bit character set has 94 graphic characters. The graphic characters in-
clude letters with accents and diacritical marks, used in many European lan-
guages. There are also special symbols, such as currency signs.
When you first turn on your terminal, you automatically select the ASCII char-
acter set and the DEC Supplemental Graphic set. The terminal maps the
ASCII set into its GL table, and the DEC Supplemental Graphic set into its
GR table. Together, these two character sets are known as the DEC
Multinational character set (Figure 2-5).
COLUMN
1
2
3
4
5
6
7
ROW
bs BITS
b?
b6
bb
01 B3 52 b1
1
1
]
1
NUL
□
DLE
20
16
10
SP
40
32
20
60
48
30
@
100
40
p
120
80
50
x
140
96
60
p
160
112
7C
1
i
SOH
;
DC1
(XON>
21
17
i
41
33
21
1
61
49
3!
A
101
41
Q
121
81
51
a
97
61
q
161
113
2
10
STX
2
2
2
DC2
22
12
Tl
42
34
22
2
62
bO
32
B
102
66
42
R
122
82
52
b
142
96
62
r
162
3
11
ETX
3
3
3
DC 3
(XOFF)
23
19
13
#
43
35
23
3
63
51
33
C
103
57
43
S
B3
53
c
143
99
s
163
115
73
4
10
EOT
a
4
DC4
24
20
S
44
36
24
4
64
52
34
D
104
68
44
T
124
84
54
d
144
100
64
t
164
116
5
10 1
ENQ
5
5
5
NAK
25
21
15
/
45
37
25
5
65
53
35
E
105
69
45
U
35
55
e
145
101
65
u
1S5
117
75
6
110
ACK
6
6
SYN
26
22
16
A
46
38
26
6.
66
54
36
F
106
46
V
126
36
56
f
146
102
V
166
76
7
1-11
BEL
7
7
7
ETB
71
23
17
'
47
39
27
7
67
55
37
G
107
71
47
w
127
87
57
9
147
103
67
w
'67
119
77
8
10
BS
10
a
CAN
3(1
24
IE
(
SO
40
28
8
70
S6
3a
H
110
72
48
X
130
58
h
150
104
6E
X
170
120
78
9
10 1
HT
9
9
EM
31
25
)
51
41
29
9
71
57
39
1
73
49
Y
131
89
59
i
•51
105
69
y
•71
121
79
10
10 10
LF
12
10
SUB
32
26
4t
52
42
2A
72
58
3A
J
112
74
2
132
90
5A
i
152
106
6A
z
172
122
11
10 11
VT
13
B
ESC
33
27
IB
♦
53
43
2B
;
73
59
3B
K
75
4B
[
133
91
5B
k
153
107
66
<
173
123
7B
12
110
FF
12
C
FS
34
28
,
54
44
?C
<
74
80
3C
L
114
4C
\
134
92
5C
1
154
108
6C
1
174
124
7C
13
110 1
CR
15
13
D
GS
35
29
ID
•
55
45
20
■
75
61
3D
M
115
77
4D
]
13b
93
5D
m
155
109
6D
}
175
125
7D
14
1110
SO
E
RS
36
30
1E
46
2E
>
76
62
3E
N
116
78
4E
A
136
94
5E
n
156
110
6E
**•
176
126
7E
15
SI
17
IS
F
US
37
31
1F
/
57
47
2F
?
77
63
3F
l 17
79
4F
-
137
95
5F
o
111
6F
DEL
177
127
7F
GL CODES
(ASCII GRAPHIC )
KEY
CHARACTER
ESC
33
27
IB
MA-0S93-B3
Figure 2-5 DEC Multinational Character Set
(Left Half - CO and GL Codes)
CHARACTER ENCODING 21
NOTE: All control function descriptions in this manual assume that the termi-
nal is using the DEC Multinational set.
The DEC Supplemental Graphic set is the right half of Figure 2-5. The CI
controls are in columns 8 and 9. The graphic characters are in columns 10
through 15.
You can select the DEC Supplemental Graphic set as the default by using con-
trol functions or set-up. You can only use the DEC Supplemental Graphic set
in VT300 mode.
8
9
10
11
12
13
14
15
COLUMN
1
i
i
i
i
1 ,
" b 7 BITS
a
,
c
1
1
i
T
b5
54 03 b2 bl
ROW
200
22D
'/////
240
o
260
300
.120
340
360
128
BO
DCS
144
90
W/a
160
AO
1/6
SO
A
192
CO
208
DO
a
224
60
240
FO
201
221
241
J61
r
A
ini
1?1
141
Tfil
129
PU1
145
I
161
±
177
193
N
209
225
241
1
1
81
B1
CI
L)l
E1
202
222
242
2
?F?
A
A
302
322
A
342
*
167
13D
PU2
146
c
162
176
194
210
226
742
10
?
82
92
A3
B2
C2
D2
E2
VI
203
223
243
3
263
«*
303
323
141
3fi1
131
STS
147
£
163
179
A
195
211
227
243
11
3
83
93
A3
B3
C3
D3
b3
F3
204
224
244
264
304
A
324
144
A
IND
133
CCH
148
164
1HU
A
196
212
22B
244
10
4
84
94
A4
C4
D4
E4
F4
205
225
241
765
305
175
NEL
133
MW
149
Y
165
M
181
A
197
213
a
?7fl
245
10 1
5
85
95
A5
B5
C5
D5
E5
F5
7Dfi
226
246
?fifi
306
V>F,
346
SSA
134
SPA
150
166
11
182
/E
198
214
a
230
246
110
6
36
96
A6
B6
C6
D6
t«
(-6
207
227
247
267
307
127
347
ESA
135
87
EPA
151
97
§
A7
183
H7
9
199
C7
CE
215
D7
9
231
E7
OB
247
F7
111
7
210
?m
250
270
110
1511
170
HTS
136
88
152
98
JO
168
AS
184
E
200
C8
216
DB
e
232
E8
248
FB
10
8
211
231
251
771
r
311
151
HTJ
137
153
(c)
1R9
185
201
u
217
e
733
U
749
10 1
q
aa
99
A9
m
C9
UH
E9
F9
212
232
a
77?
k
312
3.1?
e
15?
372
VTS
138
154
170
186
202
u
218
234
u
250
10 10
in
9A
AA
BA
CA
LA
FA
213
233
253
271
313
A
in
353
PLD
13a
CSI
155
«
171
»
187
E
203
219
235
251
10 11
11
AB
B3
CB
DB
LB
t-B
214
234
254
774
154
PLU
140
SI
156
172
%
IBS
j
204
u
??n
|
236
252
1 1 □
1?
8C
9C
AC
BC
CC
DC
tc
FC
215
235
255
315
155
Rl
141
use
167
173
%
1B9
205
Y
221
237
y
253
110 1
13
80
90
AD
BD
DD
ED
FD
215
236
256
276
A
31G
^3fi
17fi
SS2
142
PM
158
174
190
206
222
73B
254
1110
14
8E
9E
AE
BL
ce
DE
EE
FE
217
237
757
?77
317
1S7
W4
SS3
143
APC
159
175
191
207
It
223
•.•
219
755
1111
15
BF
9F
AF
BK
CF
DF
EF
FF
GR CODES
(DEC SUPPLEMENTAL GRAPHIC )
Figure 2-5 DEC Multinational Character Set
(Right Half — CI and GR Codes)
22 CHARACTER ENCODING
ISO Latin Alphabet Nr 1 Supplemental Character Set
This 8-bit character set has 96 graphic characters. The graphic characters are
similar to those in the DEC Supplemental Graphic set. The ISO Latin-1 sup-
plemental set includes letters with accents and diacritical marks, used in many
European languages. It also has other special symbols and letters, not included
in the DEC Supplemental Graphic set.
Figure 2-6 shows the ISO Latin-1 supplemental set. The CI controls are in
columns 8 and 9. The graphic characters are in columns 10 through 15.
You can select the ISO Latin-1 supplemental set as the default by using control
functions (Chapter 5) or set-up. The combination of the ASCII character set in
GL and the ISO Latin-1 supplemental set in GR is called the ISO Latin
Alphabet Nr 1 character set.
You can only use the ISO Latin-1 set in VT300 mode.
8
9
10
11
12
13
14
15
COLUMN
1
1
i
i
" „, BITS
b6
b5
b4 b3 b2 bl
ROW
30Q
128
30
DCS
220
90
NBSP
240
160
AD
°
260
176
BO
\
A
300
193
CC
■e
320
2D8
DO
a
340
224
eo
%
360
240
FO
201
129
81
PU1
221
US
91
i
241
161
±
261
177
B1
r
A
301
193
CI
N
321
209
D1
a
341
225
El
n
361
241
M
1
1
202
no
82
PU2
222
146
92
t
242
162
A2
2
262
17B
B2
A
A
3G2
194
C2
372
210
D2
k
34.2
22B
E2
o
362
242
F2
1
2
203
131
83
STS
223
147
y3
£
243
163
A3
3
263
179
A
303
195
C3
r
323
211
D3
a"
343
227
E3
*
o
363
243
F3
11
3
IND
204
132
84
CCH
224
148
94
»
244
164
A4
r
264
180
B4
V
304
196
C4
A
324
212
04
a"
344
223
E4
&
364
244
F4
10
4
NEL
205
133
85
MW
225
143
95
X
245
165
A5
M
265
1B1
85
A
305
197
C5
325
213
□6
a
345
229
E5
o
365
245
F5
10 1
5
SSA
206
134
86
SPA
226
150
96
1
1
246
166
A6
H
182
B6
/E
306
19E
326
D6
as
346
230
E6
o
366
246
F6
110
6
ESA
207
135
87
EPA
227
97
§
247
167
A7
267
183
B7
?
307
199
C?
X
327
215
D7
5
347
231
E7
-r
367
247
F7
111
7
HTS
210
136
88
230
152
98
II
250
168
A8
9
270
184
B8
E
310
200
ce
330
216
DB
e
350
232
370
24B
F8
10
8
HTJ
137
85
231
153
99
©
251
169
A9
1
271
185
89
e
E
311
201
C9
u
331
217
D9
w
e
351
233
ES
\
U
371
249
F9
10 1
9
VTS
212
138
8A
232
154
9A
a
252
170
AA
272
186
BA
A
E
312
202
CA
1
u
332
218
DA
4
362
234
EA
w
u
372
250
FA
10 10
10
PLD
213
139
SB
CSI
233
155
98
«
253
171
AS
»
273
137
V
313
203
C8
A
u
333
219
DB
V
353
235
EB
A
U
3/3
251
F8
10 11
11
PLU
140
ST
234
15G
9C
—y
254
172
AC
%
274
1B8
BC
I
314
204
CC
if
334
220
DC
1
354
236
EC
*u
374
252
FC
110
12
Rl
215
141
8D
OSC
235
157
9D
—
255
AD
%
275
189
BD
r
I
315
205
CO
V
335
221
DD
r
355
237
ED
V
375
253
FD
, , o ,
13
SS2
216
142
3E
PM
J36
15S
9E
®
2&6
174
AE
%
276
190
BF
f
315
206
CE
p
336
222
DE
A
1
356
238
FE
P
376
254
FE
1110
14
SS3
217
143
BF
APC
237
159
9F
-
257
175
AF
c
277
191
V
317
207
CF
JJ
337
223
OF
V
357
239
EF
V
377
255
FF
, , , ,
15
-CI CODES ■
GR CODES
ISO LATIN-1 SUPPLEMENTAL GRAPHIC
MA-OS94D-83
Figure 2-6 ISO Latin Nr 1 Supplemental Character Set
CHARACTER ENCODING 23
National Replacement Character Sets (NRC Sets)
The NRC sets provide character sets for many European languages. There are
12 NRC sets. Each is a 7-bit character set with 94 graphic characters. The
NRC sets are similar to the ASCII set, except for a few characters.
NOTE: Digital recommends that you operate the terminal in an 8-bit environ-
ment. The NRC sets are only provided for compatibility with 7-bit environ-
ments.
Table 2-1 lists the characters in each NRC set that are different from the
ASCII set. To use an NRC set, you must select national replacement character
set mode. You can select this mode by using a control function or set-up. You
can only use one NRC set at a time. The NRC set used depends on the key-
board selected in set-up, as follows.
Keyboard
United Kingdom
Danish
Dutch
Finnish
Flemish
French/Belgian
French Canadian
German
Italian
Norwegian
Portuguese
Spanish
Swedish
Swiss (French)
Swiss (German)
NRC Set
United Kingdom
Norwegian/Danish
Dutch
Finnish
French
French
French Canadian
German
Italian
Norwegian/Danish
Portuguese
Spanish
Swedish
Swiss
Swiss
24 CHARACTER ENCODING
Table 2-1 National Replacement Character Sets
Ch«racter Set
2/3
4/0
5/11
5/12
5/13
5/14
ASCII
#
@
I
\
]
"
United Kingdom
£
®
I
\
I
,«;'
Dutch
%
y
\>7
Finnish
#
@
A
6
A
French
£
a
o
c
§
French Canadian
# .
a
a
c
e
I
German
#
■§
A
6
*
Italian
£
§
: .©■■
c
e
Norwegian/Danish
# .
@
/E
A
"
Portuguese
#
@
A
C
... .
Spanish
£
§
'
ft
6
'■
Swedish
.#■■
E
A
6
A
Swiss
u
a
e
c
e
J
Character Set
5/15
6/0
7/11
7/12
7/13
7/14
ASCII
i
I
J
s^iWSS
United Kingdom
r
J
■ '■ •
Dutch
f
'/4
.'■^ ■ ■ .'
Finnish
a
6
e
U
French
4
u
e ..
French Canadian
1
Li
8 '
German
a
6
11
R i ;
Italian
a
6
e
I
Norwegian/Danish
ae
a
§|lfll|l
Portuguese
sss
n
c
6
**
Spanish
■
o
n
c
Swedish
a
6
a
ii
Swiss
e
6
a
6
U
; ; '§ : ':'- ; : :
CHARACTER ENCODING 25
DEC Special Graphic Character Set
This 7-bit character set has 94 graphic characters. Most of the graphic charac-
ters are also in the ASCII character set. The other graphic characters include
special symbols and line-drawing characters.
Figure 2-7 shows the DEC Special Graphic set. The CO controls are in columns
and 1. The graphic characters are in columns 2 through 7.
Another name for this character set is the VT100 line-drawing character set.
The line-drawing characters let you create a limited range of pictures when you
use the VT300 as a text terminal.
You can use the DEC Special Graphic set to replace the ASCII set in GL or
the DEC Supplemental Graphic set in GR. Chapter 5 describes how to select
character sets.
COLUMN
1
2
3
4
5
6
7
BITS
B7
B6
B5
B4 B3 B2 91
o
ROW
C
NUL
DLE
20
SP
40
32
20
O
so
43
30
@
100
64
40
P
120
80
50
•
140
96
SCAM 3
160
112
70
1
Q D I
SOH
;
DC1
IXON)
17
I
33
21
1
51
49
31
A
101
65
Q
121
81
51
i
97
61
SCAN 5
161
113
71
2
10
STX
2
2
DC2
22
18
12
ii
47
34
22
2
62
50
32
B
'02
42
R
122
B2
52
\
142
98
62
SCAN 7
'52
72
3
oo't
ETX
3
3
3
DC3
IXOFF)
23
13
#
43
3
G3
51
33
C
103
67
43
S
! 23
83
53
s
143
99
63
SCAN 9
■63
115
73
4
10
EOT
:
DC4
20
14
$
36
24
4
64
52
34
D
104
68
T
121
84
54
\
100
£4
r
161
5
O'Ol
ENQ
r>
5
5
NAK
25
15
%
15
37
25
5
65
53
35
E
105
69
4b
U
125
S5
L bb
F
101
65
\
1'7
75
6
110
ACK
6
6
SYN
26
22
IB
&
45
33
26
6
66
54
36
F
'06
70
46
V
126
86
56
146
102
66
L
1 66
1 18
76
7
1 1 1
BEL
ETB
27
23
17
'
47
33
27
7
67
55
37
G
107
71
47
w
127
87
57
t
147
1C3
67
T
167
119
77
8
10
BS
10
CAN
24
13
(
40
78
8
m
56
3E
H
110
72
48
X
130
se
58
N
L
150
194
1
170
120
78
9
10 0'
HT
11
EM
25
19
)
51
9
71
57
39
I
73
49
Y
131
39
59
1
151
10E
£
121
79
10
10 10
LF
12
10
A
SUB
J?
2c
*
S2
42
2A
72
58
3A
J
]•■?
z
! 32
5A
i
15?
106
6A
£
172
122
7A
11
10 11
VT
13
ESC
33
27
IB
+
53
43
2B
;
73
59
K
■•3
75
4fi
C
133
91
5B
l
15.3
107
66
I
173
123
IB
12
; 1 o o
FF
12
FS
?A
28
,
54
2C
<
74
60
3C
L
114
76
\
92
5C
r
154
108
6C
*
174
124
7C
13
110 1
CR
■5
13
GS
35
29
ID
"
5E>
45
2D
=
75
SI
3D
M
115
77
4D
3
'35
93
5D
L
'55
109
60
£
175
125
70
14
1110
SO
16
E
RS
36
30
IE
55
46
2E
>
76
62
3E
N
P6
/8
4E
A
136
94
5F
f
156
110
6E
175
126
7F
15
SI
17
US
37
3 !
/
57
2F
7
11
53
3F
O
117
79
4F
(BLANKI
'37
95
5F
SCAN 1
'57
i=F
DEL
1 II
17 7
7F
GL CODES
(DEC SPECIAL GRAPHIC )
KEY
ESC
33
27
IB
MA-0893C-83
Figure 2-7 DEC Special Graphic Character Set
26 CHARACTER ENCODING
DEC Technical Character Set
This 7-bit character set has 94 graphic characters. The DEC Technical set has
characters and symbols often used in technical applications, such as schematic
and logic diagrams.
Figure 2-8 shows the DEC Technical set. The CO controls are in columns and
1. The graphic characters and symbols are in columns 2 through 7. You can
use the characters in positions 2/1 through 3/7 to form large composite
characters.
You can use the DEC Technical set to replace the ASCII set in GL or the
DEC Supplemental Graphic set in GR. You can only use the DEC Technical
set in VT300 mode.
BB
B7
BB
65
' ,
" .
i
• ,
1
BITS
GL
GR
GL
GR
GL
GR
GL
GR
GL
GR
GL
UK
B4 B3 B2 B1
CO
LUMN
2
10
3
11
4
12
5
13
6
14
7
15
OW
h
48
30
260
176
BO
•
• •
100
64
40
300
192
CO
n
12C
80
50
320
208
DO
- 1
140
96
60
340
224
Ed
IT
160
117
70
360
240
FO
Q '
1
4
33
21
241
161
A1
V
61
49
31
261
177
Bl
oc
101
65
301
193
*
121
5'
51
321
209
D1
a
97
341
226
El
*
161
113
361
241
Fl
10
2
r
42
34
??
242
162
L
62
50
32
262
178
82
oo
102
66
42
302
194
C2
82
52
322
210
D2
3
142
98
62
342
226
E2
P
162
72
362
242
F2
11
3
-
43
35
23
243
163
\
63
51
33
263
179
B3
f
103
67
43
303
195
C3
z
123
83
03
323
211
03
X
143
99
63
343
227
E3
a
163
115
73
363
243
F3
1
4
r
36
24
164
A4
/
6J
52
34
264
1B0
84
A
104
6B
304
196
C4
124
84
54
324
212
D4
S
100
344
228
E4
T
164
116
;4
364
244
F4
10 1
5
j
45
37
245
165
AS
- 1
65
53
35
265
05
V
105
69
45
305
197
C5
125
55
37b
213
D5
e
145
101
65
345
279
E5
c
165
75
365
245
F5
110
6
i
46
33
246
166
A6
_l
66
54
3E
266
132
B6
$
106
70
46
198
C6
V
126
86
56
214
D6
*
146
102
65
230
ES
/
166
118
76
246
F6
„ , , ,
7
r
30
2?
247
167
A?
>
67
55
37
267
183
B7
r
107
71
47
307
199
C7
A
1??
87
57
215
D7
Y
147
103
67
347
231
E7
u>
167
119
77
367
24 7
F7
10
8
L
50
40
28
250
168
A8
C
m
56
38
270
1B4
68
/*»^
110
72
48
310
200
C8
£
Be
58
33U
216
D8
n
150
104
68
350
232
E9
S
170
120
7B
370
248
F8
10 1
9
i
51
29
351
169
A9
57
39
271
185
B9
*N*
73
49
311
201
C9
T
131
H9
59
331
217
09
i
15'
105
69
351
233
E9
V)
171
171
79
371
249
F9
1 1
10
j
0?
4?
2A
252
170
AA
72
58
3A
272
186
BA
112
312
202
CA
c
132
90
5A
218
DA
e
106
6A
234
EA
t
122
7A
250
FA
10 11
11
r
43
2E
253
171
AB
73
59
3B
273
187
SB
X
113
75
4B
313
203
CB
3
133
91
333
219
DB
K
107
6B
235
EB
«-
123
7B
251
FB
1 1
12
i
54
7C
254
172
AC
<
74
60
3C
774
136
BC
A
114
76
4C
314
204
CC
n
134
82
5C
334
220
DC
X
154
108
6C
354
236
EC
t
124
7C
374
252
FC
110 1
13
^
55
46
2D
255
173
AD
—
'5
61
3D
275
139
BD
O
115
77
4D
315
205
CD
u
135
93
5D
221
DD
155
109
60
237
ED
■*
125
70
253
FD
1110
14
)
56
46
2E
256
174
AE
>
76
3E
276
190
BE
=>
116
78
4E
316
206
CE
A
136
94
SE
336
222
DE
V
15S
110
6E
356
23B
EE
I
176
126
7E
376
254
FE
, , , ,
15
\
57
47
2F
257
175
AF
/
77
63
3F
277
191
EF
11
7S
4F
317
207
CF
V
95
5F
223
DF
a
111
6F
239
EF
LEGEND
CODES
/ \
CHARACTER ,
-A
101
65
301
193
41
CI
♦NOTE:
WHEN SET IS MAPPED INTOGR.
BITB81S1 [V2 0NL.Y).
Figure 2-8 DEC Technical Character Set
CHARACTER ENCODING 27
Down-Line-Loadable (Soft) Character Set
The VT300 lets you down-line-load a character set from the host system. The
character set can have up to 96 graphic characters. You can design your own
character set, then load the set into the terminal. You can use the set in GL or
GR. Chapter 5 describes how to load and use a soft character set.
You can only use this character set in VT300 mode.
CONTROL CHARACTERS
The purpose of a control character is to control an action such as line spacing,
paging, or data flow. The terminal does not display control characters unless
you select display controls mode (described later in this chapter). There are two
groups of control characters.
CO 7-bit control characters, in columns and 1 of the 8-bit code table
CI 8-bit control characters, in columns 8 and 9 of the 8-bit code table
Table 2-2 lists the CO control characters the VT300 recognizes. Table 2-3 lists
the CI control characters the VT300 recognizes. You can also code Cl control
characters as 7-bit escape sequences. Table 2-4 lists the equivalent 7-bit se-
quences for 8-bit control characters. All three tables give column/row locations
to help you find the characters in the character sets.
Table 2-2 CO (7-Bit) €»iuj*of Characters Recognised
Name
Null
Enquiry
Bell
Backspace
Mnemonic
Column/Row
NHL
0/0
ENQ
0/5
BEL
0/7
BS
0/8
Function '
Ignored.
Sends answerback message.
Sounds the bell tone if the bell is
enabled in set-up. '.■' ■ : ■;.:■■: : ,"■•;:' ■
Moves the cursor one character position
to the left. If the cursor is at the left margin, no
action occurs.
28 CHARACTER ENCODING
Tabic 2-2 CO (7-Bit) Coni rol Chai ac toi * Recogni ted (Cont)
Name
Horizontal
tab
Mnemonic
Column/Row
HT
0/9
Line feed
LF
0/10
Vertical
tab
VT :
0/11
Form feed
FF
0/12
Carriage
return
CR
0/13
Shift out
(Locking
shift!)
SO (LSI)
0/14
Function
Interactive mode
Moves the cursor to the next tab stop. If there
are no more tab stops, the cursor moves to the
right margin. HT does not cause text to auto
wrap.
Local editing *>>.ode
Depends on the setting of erasure mode (ERM).
ERM set Moves the cursor to the next tab
stop or field boundary.
ERM reset Moves the cursor to the next unpro-
tected field boundary.
If there are no tab stops or character fields in the
scrolling region, the page scrolls to the next tab
stop or field.
Causes a line feed or a new line
operation dej ending m the setti ig - I line feed/
new line mode.
Treated as LF.
Treated as LF.
Moves the cursor to the left margin
on the current line.
Maps the Gl character set into GL. You
designate Gl by using a select character
set (SCS) sequence (Chapter 5).
CHARACTER ENCODING 29
Table 2-2 CO (7-Bit) Control Characters Recognized (Cont)
\ ■■.;.
Mnemonic
Column/Row Function
Shift in
(Locking
shift 01
SI
0/15
Device .
control 1
(XON)
DC1
1/1
Device
control 3
(XOFF)
DC3
1/3
Device
control 4
DC4
1/4
Cancel
CAN
1/8
Subst.il.uH'
SUB
1/10
Escape
ESC
1/11
Delete
DEL
7/15
Maps the GO character set into GL. You
designate GO by using a select character
set (SCS) sequence (Chapter 5).
Also known as XON. If XON/XOFF flow
control is enabled in set-up. DCl clears
DC3 (XOFF). This action causes the VT300
to continue sending characters.
Also known as XOFF. If XON/XOFF flow
control is enabled in set-up, DCS causes
the VT300 to stop sending characters. The termi-
nal cannot resume sending characters until it re-
ceives a DCl control character.
Introduces an SSI) session management
command. The VT300 and host use this control
to separate SSU commands from ANSI text and
control functions. See Chapter 14.
Immediately cancels an escape sequence,
control sequence, or device control string in pro-
gress. The VT300 does not display any error
characters. ■ ■ ■
Immediately cancels an escape sequence,
control sequence, or device control string in pro-
gress. The VT300 displays a reverse question
mark c for an error character.
Introduces an escape sequence.
ESC also cancels any escape sequence, control se-
quence, or device control string in progress.
Ignored when received, unless a
96-character set is mapped into GL. DEL is not
used as a fill character. Digital does not recom-
mend using DEL as a fill character. Use NUL
Instead. ■■■
30 CHARACTER ENCODING
Table 2-3 CI (8-Bit) Control Characters Recognized
Name
Index
Next line
Start
selected
area
End
selected
area
Horizontal
tab set
Reverse
index
Single
shift 2
Single
shift 3
Device
control
string
Set
transmit
state
Mnemonic
Cchinm/Rim-
IND
8/4
NEL
8/5
SSA
8/6
ESA
8/7
HTS
8/8
HI
8/13
SS2
8/14
SS3
8/15
DCS
9/0
STS
9/3
Function
Moves the cursor down one line in the
same column. If the cursor is at the bottom mar-
gin, the pago scrolls up. ■
Moves the cursor to the first position
on the next line. If the cursor is at the bottom
margin, the page scrolls up. ;.'. : - ':;.-->-"
Defines the cursor position as the start
of a block of data eligible to be sent
;.;fe: : the host (Chapter 9). : :. v
Defines the cursor position as the end of
a block of data eligible to be sent to
the host (Chapter 9).
Sets a horizontal tab stop at the column
where the cursor is. .
Moves the cursor up one line in the same
column. If the cursor hi at the top margin, the
page scrolls down.
Temporarily maps the G2 character set
into GL. for the next graphic character. You des-
ignate the G2 set. by using a select character set
' (SCS) sequence (Chapter 5). ' '
Temporarily maps the G3 character set
into GL. for the next graphic character. You des-
ignate the G3 set by using a select character set
(SCS) sequence (Chapter 5). : : : . :; ; .'.
Introduces a device control string.
The VT300 sends STS to the host to
request a block transmission
(Chapter' 9).
CHARACTER ENCODING 31
Table 2-3 CI (8-Bit) Control Characters Recognized (Cont)
Name
Mnemonic
Column/Row Function
Start
protected
area
SPA
9/6
End
pmtoctod
area
E P \
9/7
Control
sequence
introducer
CSI
9/11
String
terminator
ST
9/12
Operating
system
command
osc
9/13
Privacy
message
PM
9-14
Application
program
command
APC
9/15
Defines the cursor position as the start
of a character string that you cannot
edit from the keyboard.
Defines the cursor position as the end of
« character string that you cannot edit
from the keyboard. : ;: '^ : ':. :.V '{'■: :;/V;V:'.Y ;: .'
Introduces a control sequence.
Ends a device control string. You use ST
in combination with DCS.
Introduces an operating system command.*
Introduces a privacy message string.*
Introduces an application program
command.*
* The VT300 ignores all following characters, until it receives a SUB. ST. or
any other CI control character. V:'.-:. ;; .. ; -.:: ; .;v- .-'/: : . /■■■"' .-';'; ■ ■
Table 2-4 8-Bit Control Characters and Their 7-Bit Equivalents
Name
Index
Next line
8-Bit
7-Bit
Character
Sequence
IND
ESC D
8/4
1/11 4/4
NEL
ESC E
8/5
1/11 4/5
32 CHARACTER ENCODING
Table 2-4 8-Bit Control Characters and Their 7-Bit Equivalents (Cont)
Name
8-Bit
Character
7-Bit
Sequence
Start selected area
SSA
8/6
ESC F
1/11 4/6
End selected area
ESA
8/7
ESC G
1/11 4/7
Horizontal tab set
HTS
8/8
ESC H
1/11 4/8
Reverse index
RI
8/13
ESC M
1/11 4/13
Single shift 2
SS2
8/14
ESC N
1/11 4/14
Single shift 3
SS3
8/15
ESC O
1/11 4/15
Device control string
DCS
9/0
ESC P
1/11 5/0
Set transmit state
STS
9/3
ESC S
1/11 5/3
Start protected area
SPA
9/6
ESC V
1/11 5/6
End protected area
EPA
9/7
ESC W
1/11 5/7
Control sequence
introducer
CSI
9/11
ESC {
1/11 5/11
String terminator
ST
1/11
ESC \
1/11 5/12
Operating system
command
OSC
9/13
ESC 1
1/11 5/13
Privacy message
PM
9/14
esc :
1/11 5/14
Application program
APC
9/15
ESC
1/11 5/15
CHARACTER ENCODING 33
CONTROL FUNCTIONS
You use control functions to make the terminal perform special actions in your
applications. These functions range from the simple — editing data — to the
complex — reporting on the terminal's operating state. The rest of this manual
covers the many uses for control functions. Here are some examples.
Move the cursor.
Delete a line of text.
Select bold or underlined text.
Change character sets.
Make the terminal emulate a VT52 or VT100 terminal.
You can use all control functions in text mode. There are single-character and
multiple-character control functions.
The single-character functions are the CO and CI control characters. You can
use CO characters in a 7-bit or 8-bit environment. Cl characters provide a few
more functions than CO characters, but you can only use Cl characters directly
in an 8-bit environment.
Multiple-character functions provide many more functions than the CO and Cl
characters. Multiple-character functions can use control characters and graphic
characters. There are three basic types of multiple-character functions.
escape sequences
control sequences
device control strings
Many sequences are based on ANSI and ISO standards, and are used through-
out the industry. Others are private sequences created by manufacturers like
Digital for specific families of products. ANSI sequences and private sequences
follow ANSI and ISO standards for control functions.
In this manual, private control functions created by Digital have the prefix
DEC in their mnemonic name. For example, column mode has the mnemonic
DECCOLM. All other control functions are standardized.
The following sections describe the format for escape sequences, control se-
quences, and device control strings.
PROGRAMMING TIP: When you use control functions, remember that the bi-
nary codes define a function — not the graphic characters. This manual uses
graphic characters from the DEC Multinational character set to show control
functions. If you use another character set, the graphic characters for control
functions may change, but the code is always the same.
34 CHARACTER ENCODING
Sequence Format
This manual shows escape and control sequences in their 8-bit format. You can
also use equivalent 7-bit sequences (Table 2-4).
The 8-bit format uses the CO and CI control characters and ASCII characters
from the DEC Multinational character set. The sequences also show each cha-
racter's column/row position in the character set table, below the character. The
column/row code eliminates confusion over similar looking characters such as
(3/0) and O (4/15).
NOTE: Spaces appear between characters in a sequence for clarity. These
spaces are not part of the sequence. If a space is part of the sequence, the SP
(2/0) character appears.
Escape Sequences
An escape sequence uses two or more bytes to define a specific control func-
tion. Escape sequences do not include variable parameters, but may include in-
termediate characters. Here is the format for an escape sequence.
ESC I F
1/11 2/0 to 2/15 3/0 to 7/14
Escape Intermediate Final
characters character
(zero or more (one character)
characters)
ESC introduces escape sequences. After receiving the ESC control character,
the terminal interprets the next received characters as part of the sequence.
I represents zero or more intermediate characters that can follow the ESC
character. Intermediate characters come from the 2/0 through 2/15 range of the
code table.
Fj6 the final character. This character indicates the end of the sequence. The
final character comes from the 3/0 through 7/14 range of the code table. The
intermediate and final characters together define a single control function.
For example, the following escape sequence changes the current line of text to
double-width, single-height characters.
ESC # 6
1/11 2/3 3/6
CHARACTER ENCODING 35
Control Sequences
A control sequence uses two or more bytes to define a specific control function.
Control sequences usually include variable parameters. Here is the format for a
control sequence.
CSI P...P I...I F
9/11 3/0 to 3/15 2/0 to 2/15 4/0 to 7/14
Control Parameter Intermediate Final
sequence (zero or more (zero or more (one character)
introducer characters) characters)
CSI is the control sequence introducer. You can also use the equivalent 7-bit
sequence, ESC (1/11) [ (5/11), as a substitute for CSI. After receiving CSI, the
terminal interprets the next received characters as part of the sequence.
P...P are parameter characters received after CSI. These characters are in the
3/0 to 3/15 range in the code table. Parameter characters modify the action or
interpretation of the sequence. You can use up to 16 parameters per sequence.
You must use the ; (3/11) character to separate parameters.
All parameters are unsigned, positive decimal integers, with the most signifi-
cant digit sent first. Any parameter greater than 9999 (decimal) is set to 9999
(decimal). If you do not specify a value, a value is assumed. A value or
omitted parameter indicates a default value for the sequence. For most se-
quences, the default value is 1.
NOTE: All parameters must be positive decimal integers. Do not use a decimal
point in a parameter — the terminal will ignore the command.
If the first character in a parameter string is the ? (3/15) character, it indicates
that DEC private parameters follow. The terminal interprets private param-
eters according to ANSI X3.64 and ISO 6429.
The VT300 processes two types to parameters, numeric and selective.
Numeric Parameters - A numeric parameter indicates a number value such as
a margin location. In this manual, numeric parameters appear as actual values
or as Pn, Pnl, Pn2, and so on.
The following is an example of a control sequence with numeric parameters.
36 CHARACTER ENCODING
CSI
5
♦
2
r
9/11
3/5
3/11
3/2 3/0
7/2
Control
First
Delimiter
Second
Final
sequence
numeric
numeric
character
introducer
parameter
parameter
This sequence sets the top and bottom margins of the current page. The top
margin is at line 5, the bottom is at line 20. The ; (3/11) separates the two
parameters.
Selective Parameters - A selective parameter selects an action associated with
the specific parameter. In this manual, selective parameters usually appear as
Ps, Psl, Ps2 and so on.
The following is an example of a control sequence using selective parameters.
CSI
9/11
Control
sequence
introducer
1
3/1
First
selective
parameter
3/11
Delimiter
4
3/4
m
6/13
Second Final
selective character
parameter
This control sequence turns on the bold and underline attribute at the the cur-
sor position. The parameters are 1 (indicating the bold attribute)and 4 (indicat-
ing the underline attribute). The ; (3/11) delimiter separates the two
parameters.
I...I are zero or more intermediate characters received after CSI. These charac-
ters are in the 2/0 to 2/15 range.
F is the final character from the 4/0 to 7/14 range. The final character indi-
cates the end of the sequence. The intermediate and final characters together
define a control function. If there are no intermediate characters, the final char-
acter defines the function.
Device Control Strings
Device control strings (DCS), like control sequences, use two or more bytes to
define specific control functions. However, a DCS also includes a data string.
Here is the format for a device control string.
CHARACTER ENCODING 37
DCS
P...P
I...I
F
Data string
ST
9/0
3/0
2/0
4/0
%$:%t%%t%i%:%i$i$:%%:
9/12
to
to
to
3/15
2/15
7/15
Device
Zero or
Zero or
Final
String
String
control
more
more
terminator
string
para-
inter-
introducer
meters
mediates
DCS is the device control string introducer. DCS is the CI control character at
position 9/0. You can also use the equivalent 7-bit sequence, ESC (1/11) P (5/0).
After receiving DCS, the terminal processes the next received characters as
part of the string function.
P..P are parameter characters received after DCS. Parameter characters are in
the 3/0 to 3/15 range. They modify the action or interpretation of the device
control string. You can use up to 16 parameters per string. Each parameter is
separated with a ; (3/11) character. These characters follow the same rules as in
a control sequence. See the "Control Sequences" section in this chapter.
I...I are zero or more intermediate characters received after CSI. These charac-
ters are in the 2/0 to 2/15 range.
F is the final character in the 4/0 to 7/14 range. The final character indicates
the end of the string. The intermediate and final characters define the string.
If there are no intermediates, the final character defines the string.
Data string follows the final character and usually includes several definition
strings. Each definition string can be several characters in length. Individual
strings are separated by the ; (3/11) delimiter.
ST is the string terminator. ST (9/12) indicates the end of a string. You can
also use the equivalent 7-bit sequence, ESC (1/11) \ (5/12).
The following is an example of a device control string.
DCS
1
u
% 5
ST
9/0
3/0
2/1
7/5
2/5 3/5
9/12
Device
Para-
Inter-
Final
Data
String
control
meter
mediate
string
terminator
string
introducer
38 CHARACTER ENCODING
This device control string assigns the DEC Supplemental Graphic set as the
user-preferred supplemental set.
Using Control Characters in Sequences
You can use control characters — ESC, CAN. and SUB — to interrupt or re-
cover from errors in escape sequences, control sequences, and device control
strings.
• You can send ESC (1/11) to cancel a sequence in progress and begin
a new sequence.
• You can send CAN (1/8) to indicate the present data is in error or
to cancel a sequence in progress. The VT300 interprets the charac-
ters following CAN as usual.
• You can send SUB (1/10) to cancel a sequence in progress. The
VT300 interprets the characters following SUB as usual.
The VT300 does not lose data when errors occur in escape or control sequences
and device control strings. The terminal ignores unrecognized sequences and
strings, unless they end a current escape sequence.
7-Bit Code Extension Technique
You can represent all Cl control characters as 7-bit escape sequences. You can
use the Cl characters indirectly, by representing them as 2-character escape
sequences. ANSI calls this technique a 7-bit code extension. The 7-bit code ex-
tension provides a way of using Cl characters in applications written for a 7-bit
environment. Here are some examples.
8-Bit
7-Bit Code Extension
Cl Character
Escap
e Sequence
CSI
ESC
[
9/11
1/11
5/11
SS3
ESC
O
8/15
1/11
4/15
IND
ESC
D
8/4
1/11
4/4
DCS
ESC
P
9/0
1/11
5/0
CHARACTER ENCODING 39
In general, you can use the 7-bit code extension technique in two ways.
• You can represent any Cl control character as a 2-character escape
sequence. The second character of the sequence has a code that is
40 (hexadecimal) and 64 (decimal) less than that of the the Cl
character.
• You can make any escape sequence whose second character is in the
range of 4/0 through 5/15 one byte shorter by removing the ESC
character and adding 40 (hexadecimal) to the code of the second
character. This generates an 8-bit control character. For example,
you can change ESC [ to CSI with this method.
WORKING WITH 7-BIT AND 8-BIT ENVIRONMENTS
There are three requirements for using one of the terminal's 8-bit character
sets.
• Your program and communication environment must be 8-bit
compatible.
• The terminal cannot be in national replacement character set mode
(DECNRCM).
• The terminal must operate in VT300 mode. When the terminal oper-
ates in VT100 mode or VT52 mode, you are limited to working in a
7-bit environment.
The following sections describe conventions that apply in VT300 mode.
Conventions for Codes Received by the Terminal
The terminal expects to receive character codes in a form compatible with 8 -bit
coding. Your application can use the CO and Cl control characters, as well as
the 7-bit Cl code extensions, if necessary. The terminal always interprets these
codes correctly.
When your program sends GL or GR codes, the terminal interprets the charac-
ter codes according to the graphic character sets in use. When you turn on or
reset the terminal, you automatically select the DEC Multinational character
set. This mapping assumes the current terminal mode is VT300 mode.
40 CHARACTER ENCODING
Conventions for Codes Sent by the Terminal
The terminal can send data to an application in two ways.
• Directly from the keyboard
• In response to commands from the host (application or operating
system)
Most function keys on the keyboard send multiple-character control functions.
Many of these functions start with CSI (9/11) or SS3 (8/15), which are Cl char-
acters. If your application cannot handle 8-bit characters, you can make the
terminal automatically convert all Cl characters to their equivalent 7-bit code
extensions before sending them to the application. To convert Cl characters,
you use the DECSCL commands described in Chapter 4.
By default, the terminal is set to automatically convert all Cl characters sent
to the application to 7-bit code extensions. However, to ensure the correct
mode of operation, always use the appropriate DECSCL commands.
NOTE: In VT300 mode, the terminal can send GR graphic characters to an
application, even if the application cannot handle 8-bit codes. However, in a
7-bit environment, the terminal sends Cl controls as 7-bit escape sequences and
does not send 8-bit graphic characters.
New programs should accept both 7-bit and 8-bit forms of the Cl control
characters.
DISPLAY CONTROLS MODE
The VT300 lets you display control characters as graphic characters, when you
want to debug your applications. In this mode, the terminal does not perform
all control functions.
To select this mode, you must set the Control Representation feature in the
Set-Up Display screen to Display Controls. You cannot select this mode with
an escape sequence.
The effect of the Display Controls setting depends on the operating mode you
use.
In VT300 mode
When you select Display Controls, the terminal temporarily loads a special
graphic character set into CO, GL, Cl, and GR. Figure 2-9 shows this special
set, called the display controls font. The terminal uses this font to display con-
trol characters on the screen.
CHARACTER ENCODING 41
In VT52 or VT100 mode
When you select Display Controls, the terminal temporarily loads the left half
of the display controls font into CO and GL. The terminal uses this half of the
font to display all CO and GL characters. {CI and GR are meaningless in VT52
or VT100 mode.)
COLUMN
1
2
3
4
5
6
7
ROW
us BITS
b7
b6
b5
b4 b3 b? bl
a
1
a
1
N
u
L
D
20
16
10
SP
40
32
20
60
48
30
®
100
64
40
p
120
80
50
\
140
96
60
P
160
112
70
1
1
\
i
D
21
17
I
33
1
61
49
31
A
101
65
Q
121
SI
51
a
(41
97
61
q
16!
113
71
2
10
X
2
2
2
\
22
18
12
?i
42
34
22
2
62
50
32
B
102
66
42
R
122
82
52
b
142
88
62
r
162
72
3
D 1 1
X
3
3
D
C
3
23
19
13
#
43
35
23
3
63
51
33
C
103
67
43
S
123
83
53
c
143
99
63
s
163
115
73
4
1.00
T
'
\
24
20
$
44
36
24
4
64
52
34
D
104
68
T
124
84
54
d
144
100
64
t
164
116
74
5
1 1
e
N
Q
5
5
5
N
A K
25
21
15
%
45
37
25
5
65
53
35
E
105
69
45
U
125
35
55
•
145
10.
65
u
165
117
75
6
110
A
C
K
6
6
6
N
26
22
16
&
46
38
26
6
66
64
36
F
106
70
46
V
126
86
56
f
146
102
66
V
166
118
76
7
1 : 1
B
E
L
7
E
T
B
27
23
'
47
30
7
67
55
37
G
107
71
47
w
127
87
57
9
147
103
67
w
167
119
77
8
1 C
1
to
8
8
C
\
30
13
(
50
40
23
8
m
56
38
H
110
72
48
X
130
88
58
h
150
68
X
no
120
78
9
i o a i
H
T
9
E
M
31
19
)
51
29
9
57
39
I
49
Y
131
89
59
i
151
105
69
y
171
121
79
10
10 10
L F
12
10
c
32
26
1A
*
52
42
2A
72
58
3A
J
74
z
132
90
i
152
106
6A
z
172
122
7A
11
10 11
V
T
13
11
B
E
S
c
33
2?
IB
+
53
43
2B
;
73
59
3B
K
113
75
4B
C
133
91
5Q
k
153
107
66
<
173
173
7B
12
1 "l □
F
F
12
C
F
S
34
23
1C
,
54
2C
<
74
60
3C
L
76
4C
\
134
92
5C
1
154
108
GC
1
174
124
7C
13
110 1
C R
"5
13
D
G
S
35
29
ID
-
55
45
20
=
75
61
3D
M
115
77
4LP
]
135
93
m
155
109
60
>
175
125
7D
14
1110
s
16
E
R
S
36
30
IE
56
46
2E
>
76
62
3E
N
116
7B
4E
A
136
94
5E
n
156
HO
6E
~-
176
126
7E
15
s
1
17
15
F
%
37
31
IF
/
57
47
2F
7
77
63
3F
117
79
4F
-
137
96
5F
o
15?
Ill
6F
■*
177
127
7F
GL CODES
"(ASCII GRAPHIC )"
KEY
Character
ESC
33
27
1B
OCTAL
DECIMAL
MA-0893-83W
Figure 2-9 Display Controls Font (Left Half)
42 CHARACTER ENCODING
Exceptions
Some control functions still work in this mode.
• LF, FF, and VT cause a carriage return and line feed (CR LF) that
move the cursor to a new line. The terminal displays the LF, FF, or
VT character before performing the new line function.
• XOFF (DC3) and XON (DC1) maintain flow control, if enabled in
set-up. The terminal displays the DC1 or DC3 character after per-
forming the control function.
• The terminal does not display SSU session management commands
(Chapter 14).
8
9
10
11
12
13
14
15
COLUMN
D
i
i
'\„BITS
li6
1)5
64 b3 L2 61
ROW
8 o
200
139
SO
D
C
S
220
H4
90
s p
240
160
Afl
°
260
175
BO
A
300
192
CO
*>
320
20a
OD
a
340
224
EO
%
360
240
FO
O Q
8
1
201
129
81
P
U
1
221
91
i
241
161
+
261
61
r
A
301
193
CI
N
321
209
01
a
341
225
El
rf
361
241
F1
1
1
8
2
202
13D
B2
\
222
92
t
242
162
A2
2
262
178
B2
A
A
302
194
C2
322
210
D2
A
a
342
226
E2
o
362
242
F2
1
2
8
3
203
131
33
s
223
U7
93
£
243
163
A3
3
263
179
63
A
303
196
C3
r
323
D3
£
343
227
t3
r
363
243
F3
11
3
I
N
D
204
132
S4
c
R
H
224
148
94
»
244
'
264
180
B4
A*
3D4
196
C4
A
324
212
D4
¥
344
228
E4
A
o
364
244
F4
10
4
N
E
L
205
133
85
M
W
225
149
95
X
165
AS
V-
181
B5
A
305
197
C5
325
213
D5
a
345
229
E5
o
355
245
F5
10 1
s
S
S
A
206
134
86
S
"a
226
ISO
96
1
246
166
A6
\
266
182
B6
/E
306
196
C6
326
214
D6
ae
346
230
E6
'o
366
246
P6
O110
6
1
A
207
135
87
E
P A
227
151
97
§
247
167
A7
267
183
a?
s
307
199
C7
X
327
215
D7
9
347
231
E7
■r
367
247
F7
111
7
H
T
S
210
136
88
%
230
152
98
II
250
A8
r
270
184
Be
E
310
2O0
C8
330
216
DB
e
350
232
E8
#
370
248
F8
10
8
H
T
J
2'1
137
89
9
3
231
153
99
©
251
169
A9
1
271
186
B9
E
311
201
C9
>
u
331
217
D9
r
e
351
233
E9
\
u
371
249
F9
10 1
9
V
T
S
212
138
8A
9
A
232
154
9A
a
252
170
AA
o
272
186
BA
A
E
312
202
CA
u
332
216
DA
4
352
234
EA
w
U
372
250
FA
1 1
10
P
213
139
8B
C
s
1
233
155
9B
«
253
171
AB
s>
273
1B7
BB
E*
313
203
ca
A
u
333
219
V
353
235
EB
u
373
261
FB
10 11
11
P
214
1*0
BC
s
T
234
156
9C
-1
754
172
AC
Va
274
1BS
BC
1
314
2D4
cc
u"
334
220
DC
1
354
236
EC
"u
374
252
FC
110
12
R
1
215
141
GD
s
c
235
157
90
-
265
173
AD
Vi
275
1B9
BD
r
1
315
205
CD
V
335
221
nn
w
1
355
237
ED
y
375
253
FO
110 1
13
1
2
216
142
8E
p
M
.'36
158
9E
®
256
174
AE
%
276
190
BE
A
1
316
206
CE
}
336
222
DE
A
356
238
EE
I
376
254
FE
1110
14
\
217
143
8F
A
237
159
9F
-
257
175
AF
L
277
191
BF
V
317
207
CF
JS
337
223
DF
V
357
239
EF
V
377
255
FF
, , , ,
15
|- — CI CODES
GR CODES
ISO LATIN-1 SUPPLEMENTAL GRAPHIC
MA-0401-86
Figure 2-9 Display Controls Font (Right Half)
CHARACTER ENCODING 43
PART 2
CONTROL FUNCTIONS
SENT TO THE HOST
KEYBOARD CODES
3
Keyboard Codes, 47
Main Keypad, 48
Standard Keys, 48
Function Keys, 50
Editing Keypad, 51
Numeric Keypad, 52
Top-Row Function Keys, 55
7-Bit Control Codes, 55
Special Cases, 58
Local Editing Mode, 58
Turning Autorepeat On and Off, 60
Unlocking the Keyboard, 61
This chapter describes the codes that the terminal can send to an application
program. The chapter assumes that you are familiar with the character-
encoding concepts described in Chapter 2.
In VT300 or VT100 mode, the keyboard keys send codes that are compatible
with ANSI standards. In VT52 mode, some keys send codes that differ from
those sent in the ANSI-compatible modes. This chapter lists VT52 codes that
differ from the ANSI-compatible codes.
The terminal can use 16 different national keyboards. This chapter describes
significant differences among the keyboards.
KEYBOARD CODES
The keyboard (Figure 3-1) has four groups of keys: a main keypad, an editing
keypad, an auxiliary keypad, and the top-row function keys.
47
TOP ROW FUNCTION KEYS
_ VISUAI ,
INDICATORS
jRF^^yTlRRRRRr TlRRRrW^T lRRPR
mm
mm
Em
-MAIN KEYPAD-
L—EDITING-J
KEYPAD
NUMERIC,
KEYPAD
V1A-0414-86
Figure 3-1 Four Key Groups (North American/U.K. Keyboard)
Main Keypad
The main keypad has standard keys and function keys. You use the standard
keys to send letters, numbers, and other symbols. You use the function keys to
send special function codes.
Standard Keys - The standard keys send alphanumeric characters. You must
use more than one key to produce some special characters.
Some standard keys vary on the different keyboards. On the North American/
United Kingdom keyboard, all standard keys are ASCII characters and send
only ASCII codes. The North American/U.K. keyboard does not have any stan-
dard keys that send DEC Supplemental Graphic or ISO Latin-1 supplemental
characters alone.
The North American/U.K. keyboard is a special case. Most other keyboards
have some standard keys that send DEC Supplemental Graphic or ISO Latin-1
supplemental characters, as well as ASCII characters. For example, many of
the European keyboards have standard keys that send characters with accent
marks or diacritical marks.
You can create any DEC or ISO Latin-1 supplemental character that is not
available on a standard key by typing a compose sequence. Chapter 6 of
Installing and Using the VT330/VT34O Video Terminal explains how to use
compose sequences.
48 KEYBOARD CODES
Each graphic character has a unique code. This code is always the same, no
matter which keyboard you use or how many keys you press to create that
character. The code is based on the character's position in the 8-bit code table
(Chapter 2).
You can use GL characters in a 7-bit or 8-bit environment. You can use GR
characters only in an 8-bit environment. VT52 and VT100 modes are intended
for use in 7-bit environments, as well as data exchange over a 7-bit host line.
VT300 mode is intended for use in 8-bit environments, as well as data ex-
change over an 8-bit host line.
Some standard keys can work as data processing keys. Every keyboard except
the North American/U.K. keyboard has some data processing keys. Data pro-
cessing keys have three or four characters on the top of their keycap, rather
than the normal two. The data processing keys send characters that are com-
monly used in data processing applications. Figure 3-2 shows an example.
You can select "Typewriter Keys" or "Data Processing Keys" in the Keyboard
Set-Up screen. When you select "Data Processing Keys," the data processing
keys send the character on the right side of their keycap. When you select
"Typewriter Keys," they send the character on the left side of their keycap.
You can select shifted (upper) character codes for these keys by holding the
Shift key down.
□Daannaaaaannnaa
HE
□□□
□En
□□□
□□□
=t=\
10 | ■
MA-0990-86
Figure 3-2 Standard Key with a Data Processing Character
(French/Belgian Keyboard)
KEYBOARD CODES 49
Function Keys - This section describes the function keys on the main keypad.
Remember, the column/row numbers that appear after a character tell you the
position of the character in the code table (Chapter 2). For example, the DEL
character is at column 7/ row 15.
Key
<X]
Tab
Return
Ctrl
Lock
Shift
(2 keys)
Space bar
Compose
Character
Function
The <X] key sends a delete character (DEL, 7/15) or a
backspace character (BS, 0/8), depending on the backar-
row key mode selected. You can select the mode by
using set-up or a control function.
The Tab key sends a horizontal tab character (HT, 0/9).
The Return key sends either a carriage return (CR,
0/13), or a carriage return (CR, 0/13) and line feed (LF,
0/10), depending on the state of line feed/new line mode
(LNM). See Chapter 11.
The Ctrl key alone does not send a code. You use Ctrl
with another key to send a control code.
The Lock key alone does not send a code. You use
Lock to set or clear the "caps lock" or "shift lock"
state. You select "caps lock" or "shift lock" in the
Keyboard Set-Up screen.
The Shift key alone does not send a code.
You use Shift with another standard key, to send the
top character shown on the key.
The space bar sends a space character (SP, 2/0).
The Compose Character key does not send a
code. Pressing Compose Character starts a compose se-
quence. You can use compose sequences to create char-
acters that do not appear on any single key (such as
characters from the DEC Supplemental Graphic set).
You can disable the Compose Character key in set-up.
See Installing and Using the VT330/VT340 Video
Terminal.
50 KEYBOARD CODES
Editing Keypad
The editing keypad includes the editing keys and arrow keys. Table 3-1 lists
the codes sent by the editing keys, and Table 3-2 lists the codes sent by the
arrow keys. Normally, you use the arrow keys to control the cursor on the
screen.
Table 3-1 Codes Sent by Editing Keys
Code Stmt
Key
VT300 Mod
e
VTJ.00, VT52 Mi»d«s
Find
CSI
1
■-
The editing keys do not
9/11
3/1
7/14
send codes in these two
modes.
Insert Hers
CSI
2
~ '.':..'
9/11
3/2
7/14
Remove
CSI
3
9/11
3/3
7/14
Select
CSI
4
.
9/11
3/4
7/14
Prev Screen
CSS
5
-'.■■■
9/ .; 1
3/5
7/14
Next Screen
CSF
6
: '~ y
9/11
3/6
7/14
KEYBOARD CODES 51
Table 3-2 Codes Sent by Arrow Keys
Cursor Key Mode Setting (DECCKM)
: : ' ANSI Mode . : " : ' VT52 Modu* ■
Key
Cursor
Applicaliou
m
CSI
A
SS3
A
9/11
4/1
8/1 5
4/1
m
CS?
B
SS3
B
9/11
4/2
8/1 ft
4/2
\-~ »[
CSI
C
SS3
C
9/11
4/3
8/: 5
4/3
E3
CSI
D
SS3
D
9/1 1
4/4
8/15
4/4
Cursor
ESC
1/1 J
Application
A
4/1
ESC B
1/11 4/2
ESC C
1/11 4/3
ESC D
1/11 4/4
ESC
1/11
ESC
1/1 i
ESC
1/11
ESC
1/11
A ■
4/1
B
4/2
: e'
4/3
D
4/4
* ANSI mode applies to VT300 and VT100 modes. VT52 mode is not compati-
':■' ble with ANSI mode. ■
Numeric Keypad
The characters sent by the numeric keypad depend on the setting of VT52
mode and keypad numeric mode. The application usually selects the application
keypad codes. However, you can select the application keypad codes in the
Keyboard Set-Up screen. See Chapter 11 for more information about the nu-
meric keypad.
Table 3-3 lists the character codes sent by the numeric keypad in ANSI modes
(VT100 and VT300) and in VT52 mode.
52 KEYBOARD CODES
Table 3-3 Codes Sent by Numeric Keypad Keys
Keypad Mode Setting (DECNKM)
ANSI Mode*
VT52 Mode*
Key
Numeric
Application
Numeric
Application
SS3
P
ESC
■ P
3/0
8/15
7/0
3/0
1/11
3/15 7/0
1
1
SS3
q
1
ES€
? q
3/1 .
8/15
7/1
3/1
1/11
3/15 7/1
2
2
S3
r :
2
ESC
? r
3/2
8/15
7/2
3/2
1/11
3/15 7/2
3
3
SS3
s
3
ESC
? s
3/3
3/15
7/3
3/3
1/11
3/15 7/3
4
4
SS3
t
4
ESC
? t
3/4
8/15
7/4
3/4
1/11
3/15 7/4
5
5
SS3
u
5
ESC
? u
3/5
8/15
7/5
3/5
1/11
3/15 7/5
6
6
SS3
V
6
ESC
? V
3/6
8/15
7/6
3/6
l.'ll
3/15 7/6
7
7
SS3
w
££:&$:^&s'K
ESC
? w
3/7
8/15
7/7
3/7
I'll
3/15 7/7
8
8
SS3
x
8 .
ESC
? X
3/8
8/15
7/8
3/8
1/11
3/15 7/8
9
9
SS3
y
9
ESC
? .v
3/9
8/15
7/9
3/9
1/11
3/15 7/9
ANSI mode applies to VT300 and VT100 modes,
patible with ANSI standards.
VT52 mode is not com-
KEYBOARD CODES 53
Table 3-3 Codes Sent by Numeric Keypad Keys (Cont)
Keypad Mode Setting (DECNKM)
.".: ; ' ANSI Mode* VT52Mode*
Key
Numeric
Application
Numeric
Application
-■"■
(minus)
SS3
m
'.■■■'■
ESC
?
m
2/13
8/15
6/13
2/13
1/11
' 3/15
6/13}
♦
(comma)
SS3
1
■V
ESC
?
1
2/12
8/15
6/12 '
/ 2/12
1/11
3/15
6/12}
.
(period)
SS3
■ n ■
. #
ESC
?
n
2/14
8/15
6/14
2/14
1/11
3/15
6/14
Enter
CR or
SS3
M
CRor
ESC
?
M
0/13
8/15
4/13
0/1 3
1/11
3/15
4/13
■ CR LP
CR
LF |
0/130/10
0/13 0/10
PF1
SS3 P
SS3
P
ESC
P
ESC
P
8/15 5/10
8/15
5/0
1/11
5/0
1/11
5/0
PF2
SS3 Q
SS3
Q
ESC
Q
ESC
Q
8/15 5/1
8/15
5/1
1/11
5/1
1/11
5/1
PF3
SS3 R
SS3
R
ESC
R
ESC
R
8/15 5/2
8/15
5/2; ■' -
1/11
5/2
1/11
5/2
PF4
SS3 S
SS3
S
ESC
S
ESC
S
8/15 5/3
8/15
5/3
1/11
5/3
1/11
5/3}
* ANSI mode applies to VT300 and VT100 modes. VT52 mode is not com-
patible with ANSI standards.
| You cannot use these sequences im a VT52 terminal.
=(= Keypad numeric mode. Enter sends the same codes as Return. You can use
line feed/new line mode (LNM) to change the code sent by Return. When
LNM is reset, pressing Return sends one control character (CR). When
LNM is set. pressing Return sends two control characters (CR. LFI.
54 KEYBOARD CODES
Top-Row Function Keys
There are 20 top-row function keys, Fl through F20. The first five keys —
labeled Hold Session, Local Print, Set-Up, Switch Session, and Break — are lo-
cal function keys that do not send codes. You use these keys to perform prede-
fined functions local to the terminal. Keys F6 through F20 send the codes
listed in Table 3-4. For more information, see Chapter 4 of Installing and
Using the VT330/VT340 Video Terminal.
7-Bit Control Characters
Table 3-5 lists the key or keys you use to send each 7-bit control characters.
This table applies to all keyboards. The 7-bit control characters are the CO
characters. You cannot send 8-bit CI control characters from the keyboard.
Table 3-4 ' '■■ ■■■'. Codes Scut by the Top-Row Function Keys .-. ' -^ ■ '/^
■;/: ■ Code Sent
Name on
Legend Strip
Hold Session
Local Print
Set-Up
Switch Session
Break
Key
Number
(Fl)*
(F2)*
(F3t*
(F4I*
IF5)*
VT30O Mntlr
VT100.
VT52 Modes
F7
F7
CSI
9/11
i
3/1
7
3/7
7/14
CSI
9/11
I
3/1
■8
7/14
* Fl through F5 are local function keys that do not send codes.
KEYBOARD CODES 55
Table 3-4 Codes Sent by the Top-Row Function Keys (Cont)
Code Sent
Name on
Legend Strip
Key
Number
VT300 Mode
VT100,
VT52 Modes
F8
PS
CSI
9/11
1
3/1
9
3/9
7/14
- . ;■ ■ ■;.■ ■■ ■ -^-U^ ■ /■ /- .-■ " v - -vv V^
F9
F9
CSI
9/11
2
3/2
3/0
7/14
: '(<.-'; : -* : ;'■'..'
F10
F10
CSI
9/11
2
3/2
1
3/1
7/14
\' : >,,/'^-- : :'
Fll (ESC)
Fll
CSI
9/11
2
3/2
3
3/3
7/14
ESC
1/11
F12IBS)
F12
CSI
9/1 J
2
3/2
4
3/4
7/14
BS
0/8
F13 (LF)
F13
CSI
9/11
2
3/2
5
3/5
7/14
LF
0/10
F14
F14
CSI
9/1 !
2
3/2
6
3/6
7/14
■'•'■■ ■ —
Help
;.. F15
CSI
9/11
2
3/2
8
3/8
7/14
:;;:■■:■— - :-;.;
Do
F16
CSI
9/11
2
3/2
9
3/9
7/14
—
F17
F17
est
9/11
3
3/3
1
3/1
7/14
'. .'— .'■':■
F18
F18
CSI
9/11
3
3/3
2
3/2
7/14
'■ _
F19
F19
CSI
9/1 1
3
3/3
3
3/3
7/14
■ —
F20
F20
CSI
9/11
3
3/3
4
3/4
7/14
—
56 KEYBOARD CODES
Table 3-5 Keys Used to Seucl 7-Bit Control Codes
Control
Code
Character
Table
Key Pressed With
Dedicated
Mnemonic
Position
Ctrl (All Modes)
PuuttioiJ Key
NUL
0/00
2 or space bar
'■'■.'—'■.■'.
SOH
0/01
'-A '■;■■■ .'
^^:^ : h^W^0 : W : :
STX
0/02
B
':;:;v:' :: ;--v : '.;:^' : ;;';;.:;:.-;' :: :-:' :
ETX
0/03
'€."'.■'
^•^^■■■ : .:h!B: : fS : i
EOT
0/04
D
i^^-^i^yM^
ENQ
0/05
E
■■■.—'■.■'■.■'
ACK
0/06
. F
; H :l : S^SStJv
BEL
0/07
■o
■■:: ; :::vV--'^ : ; ; ;v : .'.'- ; --:;'.:' ; X ; --
HS ■ .
0/08
II
F12IBSI*
HT
0/09
■ ■ I '.-.''
Tab
LI 7
0/10
"J. ■ '
F13 (LF)*
VT
0/11
K
^■^WK'U;:
IT
0/12
L
S^XV^V^:^
CR
0/!M
M
Return
SO
0/14
■ "-N- '"'■'.''■■'.'■ '
^X^a^l^^vW :
SI
0/15
.0
"0M^M^:i:^:^
DLE
1/00
P
v^|Xrloi5X. ; 'X ; XH
DC1
1/01
Q{
'■' ;: - ; : :; .: : ^- : ;r:' ::; . : .'.'' : .'" ; ' v . : ' : ''
DC2
1/02
R
:" : -:V: ; ^^X:;;:i(VX;E,fe;
DC3
1/03
S|
^'v:;: : -:^-;" ; . ;
DC4
1/04
T
';;.;':■■■'. :;^;- ; :^.;V:>';'::::' : -'.:V;./ : '
NAK
1/05
u. ■ ' . ■ ' ■
^J^^^.'
SYN
1/06
V
■ ; SrKA^^^ : : ; ;.:^- : -^V;f
ETB
1/07
w
W:. ; SS^: -il^v /';:■; v;^;;;
CAN
1/08
' x ■'■.-. ■
^S^^^Vir^^?-^^
EM
1/09
MM'&MMWM'M:
■';::: ! : ; -V:':'ffi:':- : : ;; X3;: : : ; : ;: : : .:0:i ; . :;
SUB
1/10
"■■■■%■ .■'■■■■'■'"".''■'.'
IfeS&S^CXX^SS
ESC
1/11
3or{
Fll (ESC)*
FS
1/12
4or/
''^^■xf'^^--^^
GS
1/13
■ 5 or].
: :j. ; ; ; \ ; ;;-~ ; - ; : ) :;:;
RS
■ 1/14
6or~
: S^§2^S : :^Vv^
US
1/15
7 or?
'■;;■ : :: --; ; ';..
DEL
7/15
8 '
Delete
* 7-bit control codes sent in VT100 and VT52 modes only.
} 7-bit control codes sent only when XON/XOFF support is off.
KEYBOARD CODES 57
SPECIAL CASES
This section describes special functions and modes that affect the keyboard.
Local Editing Mode
When the terminal is in local editing mode, certain keys on the editing and
numeric keypads have local editing functions. Table 3-6 lists the local editing
keys.
See Chapter 9 for details on local editing mode. Chapter 9 of Installing and
Using the VT330/VT340 Video Terminal describes the local editing keys.
Table 3-6 ' : y- -$Mfs Affected By Loral Editing Mode ; :
Interactive Mode
Locat Editing Mode
Name on Top
Name on From
. Local Editing ■, ; ■
of Key
of Key or Template
' Function '
Return
If DECLNM is set. sends a block
of text to the host.
Find
Home Cursor
Moves the cursor to the top left
corner of the scrolling region.
fnsy.-t Hero
Insert/Overstrike
Switches between insert and
overstrike modes {Chapter 8).
Remove
CLR PAGE*
Erases the characters
Clr Field
on the current page, or erases the
characters in a field.
To select this function, you press the Shift key and this key.
58 KEYBOARD CODES
Table 3-6 Keys Affected By Local Editing Mode
Interactive Mode Local Editing Mode
Name on Top
of Key
Select
Prev Screen
Next. Screen
PF1
PF2
PF3
PF4
Enter
Name era Front
of Key or Template
EDIT*
Prev P;iiy
Next Page
Tab[<— *
->i
Insert Line
Delete Line
Delete Char
(Space)
Transmit
Local Editing
Function
Switches the terminal between
interactive mode and local editing
mode.
Displays the previous page in
page memory on the screen.
Display.; the next page in ^age
memory on the screen.
Tabs to the next
unprotected field or
tab stop.
Shift-Tab tabs to the
previous unprotected
field or tab stop.
Inserts a line of character posi-
tions on the page.
Deletes a line of character posi-
tions from the current page.
Deletes a character from the cur-
rent page.
Inserts a space character or a
comma, depending on the setting
of the Keypad comma feature in
Keyboard Set-Up.
Sends a block of characters to
the host.
* To select this function, you press the Shift key and this key.
KEYBOARD CODES 59
Turning Autorepeat On and Off
The autorepeat feature makes most keys send their character repeatedly when
you hold the key down. You can turn the autorepeat feature on and off by
using the Keyboard Set-Up screen or the DECARM control function (Chapter
11).
The following keys do not repeat: Hold Session, Local Print, Set-Up, Switch
Session, Break, Compose Character, Shift, Return, Lock, and Ctrl. Shifted keys
and keys pressed with Ctrl can repeat. When the terminal is in edit mode, the
editing keys listed in Table 3-6 do not repeat.
Keys that can auto repeat usually start repeating after a delay of 0.5 seconds.
The autorepeat speed depends on the baud rate of the host system and the
type of key. At speeds of 2400 baud or above, all keys repeat 30 times per
second. At lower speeds, the keyboard is divided into three groups.
Group A Main keyboard
Group B Cursor keys and keypad keys
Group C Top-row function keys and editing keys
The keys in each group repeat at the fixed rate set by the baud rate of the
host, regardless of how many codes the key actually sends.
lost
Autorepeat Rate (Chare
cters
aud Rate
Group A
Group B
Gro
2400
30
30
30
1200
30
30
24
600
30
20
12
300
30
12
12
150
6
6
6
110
6
6
6
75
6
6
6
In general, the Transmit Rate Limiting feature in the Communications Set-Up
screen does not affect repeat rates. The terminal can send codes at the speed
of 150 characters per second at most baud rates. In local mode, keys repeat at
30 keystrokes per second.
Unlocking the Keyboard
Two conditions can cause the keyboard to lock.
• An application sends a control function to set the keyboard action
mode (KAM), as described in Chapter 11.
60 KEYBOARD CODES
• The keyboard input buffer is full.
When the keyboard is locked, all keys except Hold Session, Local Print,
Set-Up, Switch Session, and Break are disabled. Also, the keyboard's Wait indi-
cator turns on.
Any of the following events can unlock the keyboard.
• The output buffer becomes less than full (assuming KAM is not set).
• The terminal receives KAM when the output buffer is not full
(Chapter 11).
• You select Clear Communications, Reset Session, or Recall Factory
Default Settings from the Set-Up Directory screen. (Entering set-up
unlocks the keyboard. If you do not select one of these functions in
set-up, the keyboard locks again when you leave set-up.)
• The terminal performs the power-up self-test (DECTST) or a hard
reset (RIS). See Chapter 13.
KEYBOARD CODES 61
PART 3
CONTROL FUNCTIONS
RECEIVED FROM THE HOST
EMULATING VT SERIES TERMINALS
4
Level 1 (VT100 Mode), 66
Level 3 (VT300 Mode), 66
All Levels, 66
Selecting an Operating Level, 68
Sending CI Controls to the Host, 69
Select 7-Bit Cl Control Characters (S7C1T), 69
Select 8-Bit Cl Control Characters (S8C1T), 69
National Replacement Character Set Mode, 70
The VT300 terminal can operate like VT200, VT100, and VT52 series termi-
nals. This feature lets you use the VT300 with applications designed for these
terminals. You can select from two possible levels of operation.
Level 1 for VT100 operation
Level 3 for VT200 and VT300 operation (default)
When you operate the terminal at level 1, you cannot use some VT300 control
functions. Table 4-1 lists the functions you cannot use.
The following paragraphs describe other limits that apply to each operating
level. The chapter also describes how to select an operating level and how to
send 7-bit or 8-bit Cl controls to the host.
Appendix A describes how to use VT52 mode.
NOTE: Level 3 includes level 2 (VT200 operation). Applications designed for
level 2 will run in level 3.
65
LEVEL 1 (VT100 Mode)
The following limits apply to operating level 1.
• The keyboard only sends 7-bit ASCII characters.
• The terminal interprets keystrokes that send DEC Supplemental
Graphic or ISO Latin-1 supplemental characters as errors.
• The following keys do not operate.
— special-function keys, except Fll (ESC), F12 (BS), and F13 (LF)
— six editing keys
— user-defined keys
• Only the ASCII, national replacement (NRC), and DEC Special
Graphic character sets are available.
• Soft character sets are not available.
• The terminal sets the eighth bit of all received characters to 0.
• The terminal sends all CI control characters as 7-bit escape se-
quences (ESC Fe).
LEVEL 3 (VT300 Mode)
In VT300 mode, you can use all VT300 features. This mode is fully compatible
with Digital's VT200 series terminals. All keyboard functions are available. You
can use all control functions and device control strings described in this
manual.
ALL LEVELS
You can use the following features at any operating level.
Printer port
Edit mode (DECEDM) and the keyboard editing functions
Status line (You can enable or change the status line at any level.)
Session management
User windows
66 EMULATING VT SERIES TERMINALS
Table 4-1 Control Functions Ignored in Level 1 (VT100 mode)
Mnemonic
Name
DECCIR
Cursor information report
DECCTR
Color table report
DECDLD
Down-line-loadable set
DECRPDE
Report displayed extent
DECRPM
Report mode
DECRPSS
Report selection or setting
DECRQDE
Request displayed extent
DECRQM
Request mode
DECRQPSR
Request presentation state
DECRQSS
Request selection or setting
DECRQTSR
Request terminal state
DECRSPS
Restore presentation state
DECRSTS
Restore terminal state
DECSASD
Select active status display
DECSCA
Select character attribute
DECSED
Selective erase in display
DECSEL
Selective erase in line
DECSSDT
Select status display type
DECSTR
Soft terminal reset
DECTABSR
Tabulation stop report
DECTSR
Terminal state report
DECUDK
User-defined keys
DSR
Locator device port
DSR
UDK and keyboard language
ECH
Erase character
ICH
Insert character
LS2
Locking shift 2
LS3
Locking shift 3
LS1R
Locking shift 1 right
LS2R
Locking shift 2 right
LS3R
Locking shift 3 right
S7C1T
Send 7-bit Cl controls
S8C1T
Send 8-bit Cl controls
EMULATING VT SERIES TERMINALS 67
SELECTING AN OPERATING LEVEL (DECSCL)
You select the terminal's operating level by using the following select compati-
bility level (DECSCL) control sequences. The factory default is level 3 (VT300
mode, 7-bit controls).
NOTE: When you change the operating level, the terminal performs a hard re-
set (RIS). See Chapter 13 for details.
Sequence Level Selected
CSI
6
1
If
P
Level 1
VTluO mode
9/11
3/6
3/1
2/2
7/0
Level 3*
CSI
6
2
a
P
VT300 mode, 8-bit controls
9/11
3/6
3/2
2/2
7/0
CSI
6
2
*
II
P
VT300 mode, 8-bit controls
9/11
3/6
3/2
3/11
3/0
2/2
7/0
CSI
6
2
»
2
a
P
VT300 mode, 8-bit controls
9/11
3/6
3/3
3/11
3/2
2/2
7/0
CSI
6
3
II
P
VT300 mode, 8-bit controls
9/11
3/6
3/3
2/2
7/0
CSI
6
3
)
II
P
VT300 mode, 8-bit controls
9/11
3/6
3/3
3/11
3/0
2/2
7/0
CSI
6
3
)
2
a
P
VT300 mode, 8-bit controls
9/11
3/6
3/3
3/11
3/2
2/2
7/0
CSI
6
2
)
1
a
P
VT300 mode, 7-bit controls
9/11
3/6
3/2
3/11
3/1
2/2
7/0
(default)
CSI
6
3
?
1
a
P
VT300 mode, 7-bit controls
9/11
3/6
3/3
3/11
3/1
2/2
7/0
(default)
* Level 3 includes level 2.
68 EMULATING VT SERIES TERMINALS
SENDING C1 CONTROLS TO THE HOST
The VT300 can send CI control characters to the host as single 8-bit charac-
ters or as 7-bit escape sequences. You should select the format that matches
the operating level you are using. You can use the following sequences to select
the format for Cl control characters. See Chapter 2 for information on working
with 7-bit and 8-bit environments.
Select 7-Bit C1 Control Characters (S7C1T)
The following sequence causes the terminal to send all Cl control characters as
7-bit escape sequences.
ESC sp F
1/11 2/0 4/7
This sequence changes the terminal mode as follows.
Mode Before Mode After
VT300 mode, 8-bit controls
VT300 mode, 7-bit controls
VT100 mode or VT52 mode
VT300 mode,7-bit controls.
Same. Terminal ignores sequence.
Same. Terminal ignores sequence.
Select 8-Bit C1 Control Characters (S8C1T)
The following sequence causes the terminal to send Cl control characters to
the host as single 8-bit characters.
ESC sp G
1/11 2/0 4/6
This sequence changes the terminal mode as follows.
Mode Before Mode After
VT300 mode, 8-bit controls
VT300 mode, 7-bit controls
VT100 mode or VT52 mode
Same. Terminal ignores sequence.
VT300 mode, 8-bit controls.
Same. Terminal ignores sequence.
EMULATING VT SERIES TERMINALS 69
NATIONAL REPLACEMENT CHARACTER SET MODE
(DECNRCM)
The terminal has twelve 7-bit character sets for different national languages.
Only one national replacement character set is available at a time.
To use an NRC set, you must select national replacement character set mode.
When you reset this mode, the terminal uses the DEC Multinational or ISO
Latin-1 character set.
Default: Multinational
Mode
Sequence
Function
Set
(national)
CSI ?
9/11 3/15
4
3/4
2
3/2
h
6/8
The terminal uses 7-bit
characters from an NRC set
Reset
(multi-
national)
CSI ?
9/11 3/15
4
3/4
2
3/2
1
6/12
The terminal uses 7-bit
and 8-bit characters
from the DEC Multinational
or ISO Latin-1 set.
Notes on DECNRCM
When DECNRCM is reset, the VT300 operates as a level 3 termi-
nal. The terminal can send and receive 8-bit characters from the
DEC Multinational or ISO Latin-1 character set.
When DECNRCM is set (national), the VT300 operates as a level 3
terminal. However, the terminal can only send and receive 7-bit
characters. Also, the terminal uses one of the national replacement
character sets.
Setting DECNRCM causes the terminal to change character sets to
their default state (at power-up or reset).
If the North American/U.K. keyboard is currently selected in set-up,
the terminal ignores DECNRCM.
70 EMULATING VT SERIES TERMINALS
USING CHARACTER SETS
5
Selecting Character Sets, 72
Designating Character Sets (SCS Sequences), 73
Mapping Character Sets, 76
Locking Shifts, 78
Single Shifts, 79
National Replacement Character Sets, 79
Preferred Supplemental Character Sets, 80
ANSI Conformance Levels, 80
Soft Character Sets, 82
Designing a Soft Character Set, 82
Coding the Soft Character Set, 84
Down-Line-Loading Soft Characters. 90
Designating the Soft Character Set, 97
Soft Character Set Example, 98
Clearing a Soft Character Set, 101
This chapter describes how you can select different character sets to use with
your VT300 terminal. This chapter assumes you are familiar with the character-
encoding concepts described in Chapter 2.
You can use two types of character sets in the terminal, hard sets and soft
sets. Hard character sets are the character sets built into the VT300, such as
the ASCII and DEC Supplemental Graphic sets. Soft character sets are sets
that you down-line-load into the terminal from a host computer. You can design
your own soft character sets.
71
The VT300 has seven hard character sets. However, the number of hard sets
available depends on the operating mode you select, VT100 or VT300 (Chapter
4). Table 5-1 lists the hard character sets you can select at each operating
level. VT300 mode supports VT200 operation.
Table 5-1 Character Sets Available
' Level 1
Level 3
(VT100 mode)
(VT300 mode)
ASCII
Yes
All character
DEC Supplemental Graphic
No
sets are
ISO Latin- 1 supplemental
No
available.
User-preferred supplemental
No
National replacement (NRCs)
Yes
DEC Special Graphic
Yes
DEC Technical
No
Soft character sets (DRCS)
No
SELECTING CHARACTER SETS
To understand how to select character sets, you must first understand the
function of the terminal's in-use table. The in-use table contains the character
sets the terminal can currently access. You can place any two character sets in
the terminal's in-use table. The in-use table consists of the graphic left (GL)
and graphic right (GR) logical tables.
Each time you turn on the terminal, the terminal places the following default
character sets into the in-use table.
ASCII in GL
DEC Supplemental Graphic (or ISO Latin-1 supplemental) in GR
The ASCII and DEC Supplemental Graphic sets together make up the DEC
Multinational set.
You can select a different character set by following these two steps.
1. Designate the set as GO, Gl, G2, or G3.
GO through G3 are logical sets that the terminal uses to access
character sets. You can designate up to four character sets and have
them ready for use in the in-use table.
2. Map the designated set into the in-use table.
After you map the set into the in-use table, you can display or send
any character from that set using 8-bit codes.
72 USING CHARACTER SETS
Figure 5-1 shows how you select character sets. The following sections describe
the control functions you use to designate and map character sets.
IN-USE TABLE
MAPPING
FUNCTIONS: L
LOCKING
SHIFTS AND
SINGLE SHIFTS
DESIGNATING
FUNCTIONS
(SCS)
VT300 CHARACTER SETS
ASCII
DEC SUPPLEMENTAL 1
ISO SUPPLEMENTAL J
NRC SETS
DEC SPECIAL GRAPHIC
DEC TECHNICAL
DOWN-LINE-LOADABLE
USER- PREFERRED
SUPPLEMENTAL
MA-0070-86
Figure 5-1 Character Set Selection
Designating Character Sets (SCS Sequences)
You designate a hard character set as GO through G3 by using a select charac-
ter set (SCS) escape sequence. You cannot designate a 96-character set as GO.
SCS sequences use the format shown in Table 5-2. The table lists the code
used to select each available character set.
NOTE: The ISO Latin-1 supplemental character set is the only 96-character
hard set available in the terminal. All other hard sets have 94 characters.
USING CHARACTER SETS 73
Table 5-2 Designating Character Sets
ESC
liiteu*.v.H)hiw
1/1 1
********
Intermediate
Final
To Select Use
To Select
94-Character Sets
ASCII
Final
****
GO
Gi
G2
G3
2/8
2/9
2/10
+
2/1 1
96-Character Sets
Gl
G2
G3
2/13
2/14
l
2/15
DEC Supplemental
Graphic ■
ISO Latin-1
supplemental
(96 characters)
User-preferred
supplemental
(VT300 mode only)
Use
B
4/2
2/5 3/5
A
4/1
<
3/12
DEC Special Graphic
3/0
DEC Technical
>
3/14
National Replacement Character Sets*
Rrir.ish
Dutch
A
4/1
4
3/4
Only one national character set is available at a time. You must select
national mode to use national character sets. See "National Replacement
Character Sets" in this chapter.
Digital recommends using the first code shown.
74 USING CHARACTER SETS
Table 5-2 Designating Character Sets (Cont)
Intermediate
Final
To Select
Use
To Select
Use
National Replacemen
' Character Sets (Contf*
Finnish}
5 or
C
3/5
4/3 ■
French
R
5/2
French Canadian!
9 or Q
'H9 5/1
German .
K
4/11
Italian
Y
5/9
Norwegian/Danish}
or
E or 6
6/0
4/5 3/6
Portuguese
% 6
2/5 3/6
Spanish
Z
5/10
Swedish!
7 or
11
3/7
4/8
Swiss
.'/=.'. ;'V
3/18
Only one national character set is available at a time. You must select
national mode to use national character sets. See "National Replacement
Character Sets" in this chapter. ; ■ '■■■\.-; : ' ; . ; ;;
Digital recommends using the firsl cole shown.
USING CHARACTER SETS 75
Examples
• The following sequence designates the DEC Special Graphic charac-
ter set as the Gl logical set.
ESC)0
• The following sequence designates the ISO Latin-1 supplemental
character set as the G3 logical set.
ESC /A
Mapping Character Sets
After you designate a character set as GO, Gl, G2, or G3, you must map the
set into the in-use table as GL or GR. To map a set, you use locking-shift or
single-shift control functions.
Figure 5-2 shows how you use locking shifts and single shifts in VT100 mode.
Figure 5-3 shows how you use locking shifts and single shifts in VT300 mode.
IN-USE TABLE
MAPPING
FUNCTIONS
V_/ LSO (SI)
^J LS1 (SO)
© SS2
Q SS3
CO
L
1) 2) 3) (4
GO
G1
DESIGNATING
FUNCTIONS (SCSI
G2
ESC ( FINAL
ESC) FINAL
VT300 CHARACTER SETS
(7- BIT ONLY)
ASCII
DEC SPECIAL GRAPHIC
ALL NRC SETS
MA-0071-86
Figure 5-2 Designating and Mapping Character Sets
in VT100 Mode
76 USING CHARACTER SETS
IN-USE TABLE
MAPPING FUNCTIONS
(7) LSO(SI)
@ LS1 (SO)
© LS2 (SS2)
(4) LS1R
(D LS3 (SS3)
(6) LS2R
(7) LS3R
DESIGNATING FUNCTIONS (SCS)
(a) ESC ( FINAL (94-CHAR SET)
(£) ESC) FINAL (94-CHAR SET)
ESC - FINAL (96-CHAR SET)
(c) ESC * FINAL (94-CHAR SET)
ESC . FINAL (96-CHAR SET)
(5) ESC + FINAL (94-CHAR SET)
ESC / FINAL (96-CHAR SET
VT300 CHARACTER SETS
ASCI
DECSUPPLEMENTA
ISOSUPPLEMENTA
NRCSETS
*L \ US
L JsL
SER PREFERRED
SUPPLEMENTAL
DEC SPECIAL GRAPHIC f^ 300 M0DE 0NLY)
DEC TECHNICAL
DOWN- LINE-LOADABLE
MA-0072-86
Figure 5-3 Designating and Mapping Character Sets in VT300 Mode
USING CHARACTER SETS 77
Locking Shifts - When you use a locking shift, the character set remains in
GL or GR until you use another locking shift. Table 5-3 lists all locking shifts
available.
Table 5-3 Mapping Character Sets with Locking Shifts
Locking Shift
Code
Function
LSO (locking shift 0(
SI
0/15
Map GO into GL. (default)
LSI (locking shift 1)
SO
0/14
MapGl intoGL.
NOTE: The following locking shift functions are available only in
VT300modc. M'i;^ " \'l
LS1R (locking shift 1,
right! ■
ESC
1/11 7/14
MapGl intoGR.
LS2 (locking shift 2)
ESCn
1/11 6/14
Map G2 into GL,
LS2R (locking shift 2.
right)
ESC !
1/11 7/13
Map G2 into GR.
LS3 (locking shift 3)
ESC o
1/11 6/15
MapG3 intoGL.
LS3R (locking shift 3,
right)
ESC |
1/11 7/12
Map G3 into GR.
Examples
The following sequence designates the DEC Technical character set
as Gl, then maps Gl into GL.
ESC ) > SO
designate as Gl map Gl into GL
The following sequences designate the ISO Latin-1 supplemental
character set as G2, then map G2 into GR.
ESC . A ESC }
designate as G2 map G2 into GR
78 USING CHARACTER SETS
Single Shifts - You use a single shift when you want to display the next char-
acter from a different character set. A single shift maps the G2 or G3 set into
GL. The character set is active for only one character. Then the terminal re-
turns to the previous character set in GL.
The terminal has two single-shift control functions available.
Single-Shift
8-Bit
7-Bit Equivalent
Control
Character
Sequence
Function
Single shift 2
SS2
ESC N
Maps G2 into GL
8/14
1/11 4/14
for the next
character.
Single shift 3
SS3
ESC O
Maps G3 into GL
8/15
1/11 4/15
for the next
character.
Example
Suppose the ASCII character set is in GL. You want to display the alpha char-
acter from the DEC Technical character set, already designated as G3. You do
not want to replace the ASCII set just to display one character. Instead, you
can use single shift 3 to temporarily map the DEC Technical set (G3) into GL.
SS3
8/15
single
shift 3
a
6/1
alpha
character
After displaying the alpha character, the terminal maps the ASCII set (Gl)
back into GL, replacing the DEC Technical set (G3).
National Replacement Character Sets
The terminal has twelve 7-bit character sets for different national languages
(Chapter 2). Only one national replacement character set is available at a time.
To use a national replacement character set, you must select national replace-
ment character set mode. When you reset this mode, the terminal uses 7-bit
and 8-bit characters from one of the multinational character sets (DEC
Multinational or ISO Latin-1). When you set this mode, the terminal uses 7-bit
characters from an NRC set.
See "National Replacement Character Set Mode" at the end of Chapter 4.
USING CHARACTER SETS 79
Preferred Supplemental Character Sets
You can assign the supplemental character set you use most often as a special
standby set. This standby set is called the user-preferred supplemental set.
This feature provides applications with an easy way to access the user's pre-
ferred supplemental set.
You can assign the DEC Supplemental Graphic or ISO Latin-1 supplemental
set as the standby set. After you assign a set, you must designate and map the
set before using it.
1. Designate the set as Gl, G2, or G3.
2. Map the set into GR.
For more information on designating and mapping sets, see "Selecting
Character Sets" in this chapter.
You can assign a supplemental character set as follows.
Assign User-Preferred Supplemental Set (DECAUPSS)
Default: DEC Supplemental Graphic
Sequence Function
DCS ! u % 5 ST
9/0 3/0 2/1 7/5 2/5 3/5 9/12
DCS 1
ST
9/0 3/1 2/1 7/5 4/1 9/12
Assigns the DEC Supplemental
Graphic set as the preferred
supplemental set.
Assigns the ISO Latin-1
supplemental set as the
preferred supplemental set.
ANSI Conformance Levels
This control function lets an application map certain character sets into the
terminal's in-use table as default sets. The character sets are based on ANSI
conformance levels, listed below. These conformance levels are from the dpANS
X3. 134.1 standard.
ANSI conformance levels represent an agreement between the sender and re-
ceiver for compatible data exchange. The control function acts as an announcer
for the data exchange that follows between the terminal and application soft-
ware. The control function selects which character sets the terminal uses by
default in the data exchange.
80 USING CHARACTER SETS
The VT300 supports three ANSI conformance levels.
ANSI Levels 1 and 2
• ASCII designated as GO.
• ISO Latin-1 supplemental designated as Gl.
• GO mapped into GL.
• Gl mapped into GR.
ANSI Level 3
• ASCII designated as GO.
• GO mapped into GL.
The announcer function is as follows.
ESC sp Final
1/11 2/0 4/?
where
Final indicates the ANSI conformance level for the following data
exchange.
Final
ANSIC
L
Level 1
M
Level 2
N
Level 3
Notes
If the terminal is reset, turned off, or changed with a set confor-
mance level (DECSCL) sequence, software must send another an-
nouncer sequence to the terminal. Otherwise, the terminal uses the
default character sets (ASCII in GL, DEC or ISO Latin-1 supple-
mental in GR).
The announcer sequence is available in VT300 mode only.
Do not confuse ANSI conformance levels with Digital conformance
levels (Chapter 4).
USING CHARACTER SETS 81
SOFT CHARACTER SETS
You can down-line-load a soft character set from the host computer into the
terminal. This feature lets you design your own soft character sets for use with
the terminal. You can only load soft character sets in VT300 mode.
NOTE: VT200 fonts may appear different on a VT300 terminal, because VT300
character cell sizes are different from those of the VT200. See the Pcmw param-
eter in Table 5-6.
The soft character set is also known as a dynamically redefinable character set
(DECS). The terminal stores the soft characters in its DRCS buffer.
NOTE: The terminal does not store the soft character set in nonvolatile RAM.
When you turn off the terminal, the soft characters are lost.
The next section describes the guidelines for designing a soft set. The sections
that follow describe how to code, load, designate, and clear a soft set.
Designing a Soft Character Set
Your terminal displays each character by turning on a series of pixels. A pixel
(picture element) is the smallest displayable unit on the screen. Each character
must fit in a limited area, called the character cell. The VT300 uses a default
character cell size of 10 x 20 pixels.
When you design a character, you should lay out a character cell on grid paper.
The little boxes on the grid paper represent pixels. You fill in the pixels that
make up the character. The next section shows an example of a character
design.
You can design characters for an 80-column or 132-column font. The largest
character cell you can use is the default size of 10 x 20 pixels (200 pixels) for
an 80-column font. Figure 5-4 shows the cell sizes for 80- and 132-column
fonts. The built-in fonts supplied by Digital follow the guidelines in Table 5-4.
You must design your characters to fit the cell. The terminal ignores any pixels
that are defined outside the cell.
Figure 5-5 shows an example of this spacing for an uppercase D character. In
this example, the character for the 80-column font has two pixel columns re-
served for spacing.
82 USING CHARACTER SETS
80-COLUMN FONT
10 PIXELS
132-COLUMN FONT
1
S
1
20 PIXEL
1
• 6PIXELE
i
i
LS
20PIXE
Figure 5-4 Character Cell Sizes for 80- and 132-Column Fonts
Table 5-4 Guidelines for Designing Soft Characters
Character Dimension
80-Column Font 132-Column Font
Cell width
Cell height
10
20
pixels
6
20
pixels
Body width
Body height
9
12
5
12
Ascender height .■'."•
Descender height
4
4
4
4.
Spacing before character
Spacing after character
1
1
USING CHARACTER SETS 83
80-COLUMN FONT
132-COLUMN FONT
CHARACTER
BODY WIDTH SPACING
WIDTH SPACING
5
CHARACTER
BODY
HEIGHT 12
MA-0074-86
Figure 5-5 Character Body Sizes for 80- and 132-Column Fonts
Coding the Soft Character Set
After you design your characters, you must code them for the terminal. This
section describes how to code soft characters. The next section describes how
to load the character codes into the terminal.
Each pixel of a soft character cell receives a binary value of or 1. A 1 bit
indicates the pixel is on, and a bit indicates the pixel is off.
The terminal receives the code for a soft character in sections, called sixels. A
sixel is a 6-bit binary code that represents a vertical column of 6 pixels on the
screen. Each bit in a sixel corresponds to a pixel on the screen. The following
example describes how to design and code a soft character.
84 USING CHARACTER SETS
Example
Suppose you want to design an uppercase D for an 80-column font.
1. Draw your design on a grid.
Use the grid for an 80-column character cell to draw your design.
Mark which pixels will be on and which pixels will be off. Your de-
sign may look like Figure 5-5.
2. Divide the character cell into columns of 6 bits each.
Use the format shown in Figure 5-6. Each 6-bit pattern represents 6
pixels, or a sixel. The least significant bit is at the top, and the
most significant bit is at the bottom. The terminal would receive the
sixel columns in order (1 to 10), starting with Group A.
12 3456789 10
MA-0075-SS
Figure 5-6 Example of an Uppercase D
in an 80-Column Font
USING CHARACTER SETS 85
Because the character cell height (20 pixels) is not a multiple of 6,
the columns on the bottom of the character cell (Group D) have only
2 bits each, bO and bl. Bits b2 through b5 in the bottom cell do not
affect the character's appearance, so they have been excluded from
Figure 5-6.
3. Convert the binary value of each sixel to its hexadecimal value.
Sixels codes are restricted to characters in the range of ? (hex 3F)
to ~ (hex 7E), so you must add an offset of hex 3F to the hex value
of each column. For example,
000000(2) = 00(16)
+ 3F(16)
110101 = 35(16)
+ 3F(16)
111111(2)= 3F(16)
+ 3F(16)
3F(16)
74(16)
7E(16)
4. Use Table 5-5 to convert each binary number to the equivalent
ASCII character.
Table 5-5 lists the results of steps 3 and 4 for each possible binary
value. All you have to do is find the 6-digit binary number for each
sixel bit pattern in your character design.
Figure 5-7 shows this conversion for the uppercase D in this
example.
You use this procedure to convert each character of your soft character set into
a string of sixel bit patterns. Then you can down-line-load your DRCS charac-
ters into the terminal, using the DECDLD device control string described in
the next section.
86 USING CHARACTER SETS
Table 5-5
Converting
Binary Code
to an ASCII C
Binary
Hex
Hex Value
Character
Value
Value
+ 3F Offset
Equivalent
000000
00
3F
?
00000 I
01
40
@
000010
02
41
A
000011
03
42
B
000100
04
43
• C " • '
000101
05
44
D
000110
06
45
E
000111
07
46
F
001000
08
47
G
001001
09
48
H
001010
A
49
I
001011
B
4A
J
001100
C
4B
K
001101
D
4C
L
001110
E
4D
M
001111
F •■ ■
4G
N
010000
10
4F ' ..
O
010001
11
50
P
010010
12
51
Q
010011
13
52
R
010100
14
53
S
010101
15
54
T ■
010110
16
55
U
010111
17
' 56
V
011000
18
57
W
011001
19
58
X
011010
1A
59
Y
011011
IB
5A
z
1 1 100
1C
5B
[
011101
ID
5C
: V
USING CHARACTER SETS 87
Table 5-5
Converting Binary Code
to an ASCII (
Binary
Hex
Hex Value
Chin-jinn-
Value
Value
+ 3F Offset
Equivalent
011110
IE
51)
■]■'■■-'■■'
Oil ill
IF
5E
- . {■■■
100000
20
SI'"
100001
21
60
i
100010
22
61
a
10001 1
23
62
■ b .
100100
24
63
: ;?:$$-M'MM\ : :i
100101
25
6-1
(1
100110
26
65
100111
27
66
W&MBM
101000
28
m
g
101001
29
08
h
101010
2A
69
3^;M : fffiS^
101011
2B
6A
:"j' ;: ..'-.-::-.'.'-:-"- : :
10 J too
2C
(JB
u
101101
2D
ec
!■■■■■'■'
101110
2E
6D
'. m ■
101111
" 2F " :
6E
n
110000
30
6F
110001
31
70
P
110010
32
71
q -^ . ■
11001 1
' 33
72
kMWW':WW:
100100
34 .
73
s
110101
35
■ 74
■•. t;. ' .
110110
36
75
'■ u
110111
37
76
■'■/ -*-'.-lV: : ■
111000
38
77
w
111001
39
78
' \ .'■ '
111010
3A
70
y
1111)11
3B
7A
Si^S^^^^HW
111100
3C
7B
; -:-;VJf : l ; :::':
111101
3D
70
llfill
111110 ■
3E
7D
*
:- : .'i.': : '.
mill '
3F ■
7E
-
88 USING CHARACTER SETS
10
iflflfl
GROUP A
110000 01000 SAME SAME 100000 000000 SAME SAME SAME SAME
>■ T > - — »— ' AS AS ' 1 ' k < ' AS AS AS AS
0022 - ? 6 6 6 6
(6/15) (4/15| (5/15) (3/15)
9 10
111111 000000 SAME SAME SAME 000001 000010 111100 000000 SAME
~ ? 2 2 2 @ A I ?9
(7/14) (3/15)
(4/0) (4/1) (7/11) (3/15)
6 7 8 9 10
B
001111 001000 SAME SAME 000100 000010 000001 000000 SAME SAME
• , ■ • , ■ AS AS • y — ' ' . ■ ' • ' ' ' ' AS AS
N G 2 2 CA@ ? 88
(4/14) j/7) (4/3) (4/1) (4/0) (3/15)
NOTE:
FOR THIS EXAMPLE. THE BITS IN GROUP D DO NOT AFFECT
THE APPEARANCE OF THE CHARACTER.
Figure 5-7 Sixel-to-ASCII Conversion
GROUP B
GROUP C
MA-0076-86
USING CHARACTER SETS 89
Down-Line-Loading Soft Characters
You can load two font renditions of your soft character set.
80-column
132-column
You should load both an 80-column and a 132-column rendition of your soft set.
Then the terminal can select the correct rendition if you change the page width
(Chapter 6).
If you only load a normal or bold rendition of the soft set, the terminal uses
the rendition that is currently available.
Do not confuse the font rendition with the actual character set. You cannot
load two different soft sets. However, you can load two renditions of the same
soft set.
You load your soft character set with a DECDLD device control string. This
control string has the following format.
NOTE: See Chapter 2 for general information about device control strings.
DCS Pfn ; Pen ; Pe ; Pcmw ; Pw ; Pt ; Pcmh ; Pcss {
Dscs Sxbpl ; Sxbp2 ;...; Sxbpn ST
where
DCS (9/0)
is the device control string introducer. DCS is an 8-bit CI character.
You can use the equivalent 7-bit sequence ESC P (1/11, 5/0) when
coding for a 7-bit environment.
Pfn ; Pen ; Pe ; Pcmw ; Pw ; Pt ; Pcmh ; Pcss
are parameter characters, separated by semicolons (3/11). Table 5-6
describes these parameters and lists their possible values. Table 5-7
describes the combinations of Pcmw, Pt, and Pcmh you can use for
80- and 132-column fonts. If you use any other combinations, the
terminal ignores the DECDLD string.
90 USING CHARACTER SETS
{ (7/11)
is the final character. It marks the end of the parameter characters
and indicates that this string is a DECDLD function.
Dscs
defines the name for the soft character set. You use this name in
the select character set (SCS) escape sequence. You use the follow-
ing format for the Dscs name.
IF
where
I
is 0, 1 or 2 intermediate characters from the range 2/0 to 2/15
in the ASCII character set.
F
is a final character in the range 3/0 to 7/14.
Examples of Dscs Names
Name Function
sp @ Defines the character set as an
2/0 4/0 unregistered soft set. This value is the recom-
mended default for user-defined sets. The value of
Pcss defines whether this set has 94 or 96
characters.
A If Pcss is 0, A defines the soft
4/2 character set as the U.K. national replacement
character set.
If Pcss is 1, A defines the soft character set as
the ISO Latin-1 supplemental set.
& % C Defines the soft character set as % C,
2/6 2/5 4/3 which is currently an unregistered set. The value
of Pcss defines whether this set has 94 or 96
characters.
USING CHARACTER SETS 91
Sxbpl ; Sxbp2 ;...; Sxbpn
are the sixel bit patterns for individual characters, separated by se-
micolons (3/11). Your character set can have 1 to 94 patterns or 1 to
96 patterns, depending on the setting of the character set size pa-
rameter (Pcss). Each sixel bit pattern is in the following format.
S...S/S...S
where
the first S...S
represents the sixels in Group A of the soft character (Figure
5-6)
/ (2/5)
advances the sixel pattern to Group B of the soft character
the second S....S
represents the sixels in Group B of the soft character.
ST (9/12)
is the string terminator. ST is an 8-bit CI character. You can use
the equivalent 7-bit sequence ESC \ (1/11, 5/12) when coding for a
7-bit environment.
After you load your soft character set, you must designate the set as GO, Gl,
G2, or G3.
Table 5-6 : c;\. DECDLD Parameter Characters
Parameter Name Description
Pfn Font Selects the DRCS font buffer to load.
number The VT300 lias two DRCS font buffers. One font
buffer h dedicated to session 1, the other to ses-
-'. : .;V'.' ; ;V ; : sion 2. Kaeh font buffer is called DECS buffer 1. '"■
"■":':': \ . ■ , Pfn has two valid values, and 1 . Both values
/: : v.-:;V : : : ; o. ; ^■■v> r ;.■■■ ;.;.': ; .>'..v : : refer to DRCS buffer ! for each session.
92 USING CHARACTER SETS
Table 5-6 DECDLD Parameter Characters (Cont)
PanmiH.pr
Pen
Name
Starting
character
i .
Erase
control
Description
Selects where to load ! he first character
in the DRCS font buffer. The location corre-
sponds to a location in the ASCII code table
(Table 2-11. For example, a Pen value of means
that the first soft character is loaded into posi-
tion 2/0 of the character table. A Pen value of 1
means position 2/1 in the table, and so on up to
Pen = 95 (position 7/15).
Pen ifr affected by the character set size. See
Pcss below.
Selects which characters to erase from
the DRCS buffer before loading the new font.
Pcmw
Character
matrix
width
= erase all characters in the DRCS buffer with
this number, width and rendition.
1 = erase only characters in locations being
reloaded.
2 — erase all renditions of the soft character set
(80-column and 132-e.olumnl.
Selects tno n^nrJnimiivhe.rutej ftli width.
VTSOOmode
= 10 pixels wide for 80 columi s,
6 pixels wide for 132 columns,
(default)
1 = illegal
2 = 5 x 10 pixel cell (VT200 compatible).
3 = «xl() pixel cell (VT200 compatible).
4 = 7x10 pixel cell (VT200 compatible).
5 = 5 pixels -.ide.
6 = 6 pixels wide.
10 = 10 pixels wide.
USING CHARACTER SETS 93
Table 5-G DECDLD Parameter Characters (Coat)
Parameter Name
Pcmw (cont)
Pw
Font
Width
Description
If you omit a Pcmw value, the terminal uses the
default character width. If the Pe parameter is 0.
Pcmw must be less than 10. Any Pcmw value
over 10 is illegal.
For VT200 compatible software: Use a Pcmw
value of 2. 3. or 4. When you use these values.
the VT300 doubles the height of the font defini-
tions in memory. This makes the soft set the
same height as the hard sets. If you use a Pcmw
value of 0, the VT300 does not double the height
and the soft set appears smaller than the hard
sets. Remember that the VT200 fonts may appear
different on the VT300. ■ : '
For fonts designed far the VT300: Use values 5
through 10. ■ '
For compatibility between VT200 and VT300 ter-
minals: Use a Pcmw value of 5. fi, or 7.
Selects the number of columns per line
(font set size).
— 8(1 columns, (default}
1 — 80 columns.
2 = 132 columns.
94 USING CHARACTER SETS
Table 5-6 DECDLD Parameter Characters (Cont)
Parameter
Name
:: ^::^y: ;: -: Description
Pt
Text or
Defines the font as a text font or
full-cell
■•' full-cell font. ' ; . .■ ' •
= text, (default)
■ 1 = tCXt. : :
2 = full cell '■ ■
Pcmh
Character
matrix
height
Full-cell fonts can individually address all pixels
in a cell.
Text fonts cannot individually address all pixels.
If you specify a text cell, the terminal automati-
cally performs spacing and centering of the
characters.
Selects the maximum character cell
height. ■';■ '■■;"■':. vv -'; : ' : ;. : -.-;'- ',■■;.; ■; ':.:■; - '<*;. ...-/.: :U :
or omitted = 20 pixels high, (default)
1 — ] pixel high.
2 = 2 pixels high. ^^2^M^rX :
3 : .:== 3 pixels high.
'•'■'■' ■ ■ .■'.. 20 = 20 pixels high. ■■ • ■ ■•'■.'.■■
: . ; ;;';-;. ■' ; : ; , : .;C ;, K ■; ; Pcmh values over 20 are illegal. If the value of
. ■ •■. '.•■.■ Pcmw is 2, 3, or 4, Pcmh is ignored.
Pcss Character Defines the character set as a 94- or
set size 96-character graphic set.
= 94-charactcr set. (default)
..-.■'■ ' •. . ■ . 1 = 96-character set. .' ■..'.■■'.''' .
The value of Pcss changes the meaning of the Pen (starting character) param-
eter above.
USING CHARACTER SETS 95
■ • Table 5-6 DECDLD Parameter Characters (Cant)
Parameter Name . ■ 'Description
Examples
' • If Pcss = (94-character set) ■ ' ' .
The terminal ignores any attempt to load characters into the 2/0 or
7/ 15 tabic positions.
Pen Specifics '
1 column 2/row 1
column 14
;\ • If Pcss - 1 (96-clmractcr set) ■'.'."' :
Pen Specifies
column 2/row
95 column 7 /row 15
Table 5-7 Valid DEC!>LB P&mneter Combmutlous
Pcimv Pt
Pcmh
Pw
80-Column Fonts
2 to 9 0. 1
2 to 10 2
1 to 20
1 to 20
0. 1
0. 1
132-Column Fonts
2 to 5 0, 1
2 to 6 2
1 to 20
1 to 20
2
2
96 USING CHARACTER SETS
Designating the Soft Character Set
You designate your soft character set the same way you designate the hard
character sets — using a select character set (SCS) sequence. You also use the
same format for the SCS sequence.
ESC Intermediate(s) Final
1/11 ********* *****
where
Intermediate(s)
are zero or more characters that designate the soft character set as
one of the logical sets, GO through G3. You use the same intermedi-
ate characters that you use for hard character sets (Table 5-2).
An intermediate character also indicates that the soft character set
is a 94- or 96-character set. Make sure you use an intermediate
character that matches the setting of the character set size param-
eter (Pcss) in the DECDLD string (Table 5-6).
Final
is the Dcsc name you used for the soft character set in the
DECDLD string.
Notes on Designating Soft Character Sets
• Replacing a soft set with a new soft set
If you use a new Dscs name when you replace the current soft set
with another soft set, then the following occurs.
— Characters from the old soft set are undefined. If you redefine
the soft set, characters currently on the screen may change.
— Any logical sets (GO, Gl, G2, G3) used to designate the old soft
set are undefined. The in-use table is also undefined.
After you load a new soft set, use a select character set (SCS) se-
quence to designate the soft set. Using SCS eliminates the confu-
sion involved with undefined characters.
USING CHARACTER SETS 97
• Replacing a hard set with a soft set
You can define a soft set that replaces one of the hard sets (such as
ASCII or DEC Special Graphic).
A soft set that replaces a hard set remains in effect until you per-
form one of the following actions.
— Clear the soft set (using the Recall Saved Settings or Recall
Factory Default Settings set-up features, or the power-up self-
test).
— Redefine the soft set (using another DECDLD string).
Soft Character Set Example
Suppose you want to create a soft character set containing a solid rectangle, a
blank, a rectangular box, and a striped rectangle. This example shows how you
would
• down-line-load the set,
• designate the set as Gl, and
• map the Gl set into GL.
NOTE: Make sure the terminal is in VT300 mode before you try to load a soft
character set. You cannot load soft sets in VT100 mode.
1. You could use the following DECDLD string to load your character
set. (The string is shown divided into sections for clarity.)
DCS
1 ; 1 ; ; 8 ; 1 ; 1 ; 20; { sp 3
/ / /
????????/????????/????????/????????
~aaaaaa~ /"??????"/"??????" /"aaaaaa"
TTTTTTTT/TTTTTTTT/TTTTTTTT/TTTTTTTT
ST
98 USING CHARACTER SETS
where
DCS (9/0)
introduces the device control string.
1;1;0;8;1;1;20;0
is the parameter string specifying the following. (See Table 5-6
for parameter definitions.)
Parameter
Pfn= 1
Pcn= 1
Pe =
Pcmw =
= 8
Pw= 1
Pt = 1
Pcmh =
20
Pcss =
Function
Loads this soft set into the DRCS font buffer.
Selects the character at row 2/ column 1 in the
ASCII table (Chapter 2) as the first character
to load.
Erases all characters in the font buffer for that
rendition.
Selects a maximum character width of 8
pixels.
Selects a font width of 80 columns.
Defines the set as a text font.
Selects a maximum character height of 20
pixels.
Defines the set as a 94-character set.
{ (7/11)
indicates the end of the parameter characters and specifies that
this sequence is a DECDLD string.
sp @ (2/0, 4/0)
defines the character set as an unregistered soft set. This value
is the recommended default value for user-defined sets. The sp
represents one space. You can use other values to define other
specific character sets.
-/-
-/-
-/-
-/
represents the first character (a solid rectangle).
USING CHARACTER SETS 99
; (3/ii)
separates the soft characters.
????????/????????/????????/????????
represents the second character (a blank).
~@@@@@ @T?????rr??????TAAAAAA"
represents the third character (a hollow rectangle).
represents the fourth character (a set of horizontal stripes).
ST (9/12)
indicates the end of the DECDLD string.
2. Now you are ready to designate the character set as Gl. You can
use the following SCS escape sequence.
ESC ) sp
where
ESC (1/11)
introduces the SCS sequence.
) (2/9)
designates the character set as Gl.
sp @ (2/0, 4/0)
selects the soft set as the set to designate as Gl. Remember,
sp @ was the name used for the soft set in the DECDLD
string.
Finally, you want to map the Gl set into the in-use table as GL.
You can map the set by sending a shift out (SO) control character.
To send the SO character, you hold down the Ctrl key and press N
key.
NOTE: For information on using shift characters, see Chapter 3.
For information on mapping sets, see "Mapping Character Sets" in
this chapter.
The soft character set should now be loaded and ready for use.
100 USING CHARACTER SETS
Clearing a Soft Character Set
You can clear a soft character set that you loaded into the terminal by using
the following DECDLD control string.
DCS 1;1;2 { sp @ ST
Any of the following actions also clear the soft character set.
• Performing the power-up self-test.
• Selecting the Recall Saved Settings or Recall Factory Default
Settings set-up features.
• Using a reset to initial state (RIS) sequence.
USING CHARACTER SETS 101
6
PAGE MEMORY
What is Page Memory?, 103
Page Memory for a Single Session, 104
Page Memory for Dual Sessions, 105
Controlling the Page Format, 106
Selecting 80 or 132 Columns per Page, 106
Set Columns per Page (DECSCPP), 106
Column Mode (DECCOLM), 106
Set Lines per Page (DECSLPP), 107
Origin Mode (DECOM), 108
Set Top and Bottom Margins (DECSTBM), 108
Moving to Another Page, 109
Next Page (NP), 109
Preceding Page (PP), 109
Page Position Absolute (PPA), 110
Page Position Backward (PPB), 110
Page Position Relative (PPR|, 111
Summary, 111
This chapter describes the control functions that affect the terminal's page
memory. The chapter covers the following topics.
• What is page memory?
• Controlling page format
• Moving through pages
This chapter assumes you are familiar with the character-encoding concepts de-
scribed in Chapter 2.
102
WHAT IS PAGE MEMORY?
Many terminals only have enough memory to store the data that appears on
their screen. The VT300 has memory to store more data than you can display
on the screen. The size of this memory is equal to 144 lines by 80 or 132
columns. You can divide this memory into one or more pages.
Page memory lets you store more text locally in the terminal. The screen can
display up to 24 lines from page memory at a time. You can use control func-
tions (such as scrolling and panning) to display the other lines.
Page memory can provide a faster response time. While the terminal displays
one page, the host can write to another (Chapter 10).
You divide page memory into a number of equal-sized pages, by selecting one
of several standard page sizes. A page in page memory is similar to a page in a
book. Each page has left, right, top, and bottom margins. You can define the
position of the top and bottom margins on a page. The left and right margins
are always set according to the current page width. You select the page format
by using control functions or set-up. This chapter describes the control
functions.
Applications can write to page memory by first addressing a page, then writing
data to the page. If the application wants write to another page, the application
must address that page.
Figure 6-1 shows the basic parts of a page. The figure shows the default page
size of 24 lines x 80 columns. Your terminal screen can display 24 lines at a
time. However, you can make the length of a page larger than the screen.
TOP MARGIN
LEFT
MARGIN
RIGHT
MARGIN
80 COLUMNS
24
LINES
BOTTOM MARGIN
MA-0079-86
Figure 6-1 A Page in Page Memory
PAGE MEMORY 103
Page Memory for a Single Session
When you use a single session, the full 144 lines of page memory are available.
See Chapter 14 for details on session management.
You can select one of the following page sizes for a single session. Figure 6-2
shows these page sizes.
6 pages of 24 lines x 80 or 132 columns
4 pages of 36 lines x 80 or 132 columns
2 pages of 72 lines x 80 or 132 columns
1 page of 144 lines x 80 or 132 columns
1PAGE
80/132
•COLUMNS-
24
LINES
J
80/1 32
-COLUMNS-
36
LINES
J
80/132
-COLUMNS-
72
LINES
80/1 32
-COLUMNS-
144
LINES
MA-0089-86
Figure 6-2 Page Sizes for a Single Session
104 PAGE MEMORY
Page Memory for Dual Sessions
When you use dual sessions, each session has 72 lines of page memory avail-
able. See Chapter 14 for details on session management.
You can select one of the following page sizes for dual sessions. Figure 6-3
shows these page sizes.
• 3 pages of 24 lines x 80 or 132 columns
• 2 pages of 36 lines x 80 or 132 columns
• 1 page of 72 lines x 80 or 132 columns
2 PAGES
80/1 32
-COLUMNS-
24
LINES
_L_
80/1 32
•COLUMNS-
36
LINES
80/132
-COLUMNS -
72
LINES
MA-0078-86
Figure 6-3 Page Sizes for Dual Sessions
PAGE MEMORY 105
CONTROLLING THE PAGE FORMAT
This section describes how to select the page size, and top and bottom margins
for page memory. You use the same basic control functions for single or dual
sessions.
Selecting 80 or 132 Columns per Page
There are two control functions that can set the page width to 80 or 132 col-
umns, DECSCPP and DECCOLM.
PROGRAMMING TIP: Digital recommends that new applications use
DECSCPP rather than DECCOLM. DECSCPP does not clear page memory or
reset the scrolling regions, as does DECCOLM. DECCOLM is provided mainly
for compatibility with previous products.
Set Columns per Page (DECSCPP)
Default: 80 columns
Sequence
CSI $ |
9/11 2/4 7/12
CSI $ I
9/11 3/0 2/4 7/12
CSI 8 $ |
9/11 3/8 3/0 2/4 7/12
CSI 1 3 2 $ |
9/11 3/1 3/3 3/2 2/4 7/12
Action
Sets each page to 80 columns.
Sets each page to 80 columns.
Sets each page to 80 columns.
Sets each page to 132 columns.
Notes on DECSCPP
If you switch from 132-column to 80-column pages, you can lose
data from page memory. Columns no longer present in page mem-
ory are lost. Make sure you set page columns before you enter data
into page memory.
Column Mode (DECCOLM)
Default: 80 columns
Mode Sequence
Set CSI ? 3 h
(132)
9/11 3/15 3/3 6/8
Action
Selects the 132-column font
to display text on the screen.
106 PAGE MEMORY
Reset CSI ? 3 1
(80) 9/11 3/15 3/3 6/12
Selects the 80-column font
to display text on the screen.
Notes on DECCOLM
• If you change the DECCOLM setting, the terminal
— sets the top and bottom scrolling margins to their default posi-
tions, and sets all pages to have 24 lines
— erases all data in page memory.
• DECCOLM does not clear data from the status line.
Set Lines per Page (DECSLPP)
This control function sets the number of lines for each page in page memory.
The number of lines you can select depends on whether you use a single ses-
sion or dual sessions.
Default: 3 pages of 24 lines
Page Length
Sequence
Dual Session
Single Session
CSI 2
9/11 3/2
4
3/4
t
7/4
3 pages of
24 lines
6 pages of
24 lines
CSI 3
9/11 3/3
6
3/6
t
7/4
2 pages of
36 lines
4 pages of
36 lines
CSI 7
9/11 3/7
2
3/2
t
7/4
1 page of
72 lines
2 pages of
72 lines
CSI 1
4
4 t
Not available
1 page of
9/11 3/1
3/4
3/4 7/4
144 lines
Notes on DECSLPP
If you switch to a smaller page size, data that was on the larger
page may be split across the smaller pages. To avoid confusion,
make sure you set the lines per page before you enter data into
page memory.
PAGE MEMORY 107
• DECSLPP usually does not change the top and bottom scrolling
margins. However, if you change the page size, and the current
scrolling margins exceed the new page size, the terminal resets the
margins to the page limits.
Origin Mode (DECOM)
This control function allows cursor addressing relative to the top and bottom
margins or the complete page. DECOM determines if the cursor position is
restricted to inside the page margins. When you power up or reset the termi-
nal, you reset origin mode.
Default: Origin at upper-left of screen, independent of margins.
Mode
Set
(Margin-
dependent)
Reset
(Margin-
independent)
Sequence
CSI ? 6 h
9/11 3/15 3/6 6/8
CSI ? 6 1
9/11 3/15 3/6 6/12
Action
Sets the home cursor position
at the upper-left corner of the
screen, within the margins. The start-
ing point for line numbers depends on
the current top margin setting. The
cursor cannot move outside of the
margins.
Sets the home cursor position
at the upper-left corner of
the screen. The starting point for line
numbers is independent of the mar-
gins. The cursor can move outside of
the margins.
Set Top and Bottom Margins (DECSTBM)
This control function sets the top and bottom margins for the current page.
You cannot perform scrolling outside the margins.
Default: Margins at page limits.
CSI
9/11
Pt
3/?
; Pb
3/11 3/?
r
7/2
where
Pt is the line number for the top margin.
Default: Pt = 1.
108 PAGE MEMORY
Pb is the line number for the bottom margin.
Default: Pb = 24, 36, 48, or 72 (depending on the number of lines per
page).
Notes on DECSTBM
• The value of Pt must be less than Pb.
• The maximum size of the scrolling region is the page size.
• DECSTBM moves the cursor to column 1, line 1 of the page.
MOVING TO ANOTHER PAGE
The following control functions let you move the cursor forward or backward to
another page in page memory. You can move in sequence or randomly.
Applications can use these control functions to select the page to write to.
Next Page (NP)
This control function moves the cursor forward to the home position on one of
the following pages in page memory. If there is only one page, the terminal
ignores NP.
Default: Move to the next page.
CSI Pn U
9/11 3/? 5/5
where
Pn indicates how many pages to move the cursor forward.
Default: Pn = 0.
If Pn is or 1, then the cursor moves to the next page in page memory.
If Pn tries to move the cursor past the last page in memory, then the
cursor stops at the last page.
Preceding Page (PP)
This control function moves the cursor backward to the home position on one
of the preceding pages in page memory. If there is only one page, the terminal
ignores PP.
PAGE MEMORY 109
Default: Move to the preceding page.
CSI Pn V
9/11 3/? 5/6
where
Pn indicates how many pages to move the cursor backward.
Default: Pn = 0.
If Pn is or 1, the cursor moves to the preceding page. If Pn tries to
move the cursor back farther than the first page in memory, the cursor
stops at the first page.
Page Position Absolute (PPA)
This control function can move the cursor to the corresponding row and column
on any page in page memory. You select the page by its number. If there is
only one page, the terminal ignores PPA.
Default: Move to the next page.
CSI Pn sp P
9/11 3/? 2/0 5/0
Pn is the number of the page to move the cursor to. If Pn is greater than
the number of the last page in memory, the cursor stops at the last page.
If Pn is less than the number of the first page, the cursor stops at the
first page.
Page Position Backward (PPB)
This control function moves the cursor backward to the corresponding row and
column on one of the preceding pages in page memory. If there is only one
page, the terminal ignores PPB.
Default: Move backward one page.
CSI Pn sp R
9/11 3/? 2/0 5/2
where
Pn indicates the number of pages to move the cursor backward. If Pn tries
to move the cursor back farther than the first page in memory, the cursor
stops at the first page.
110 PAGE MEMORY
Page Position Relative (PPR)
This control function moves the cursor forward to the corresponding row and
column on one of the following pages in page memory. If there is only one
page, the terminal ignores PPR.
Default: Move to the next page.
CSI Pn sp Q
9/11 3/? 2/0 5/1
where
Pn indicates how many pages to move the cursor forward. If Pn tries to
move the cursor beyond the last page in memory, the cursor stops at the
last page.
SUMMARY
Tables 6-1 and 6-2 list the control functions described in this chapter.
PAGE MEMORY 111
Table 6-1 Page Format Sequences
Name
Set columns per
page
Column mode
Set lines per
page
Origin mode
Set top and
bottom margins
<D) = default.
Mnemonic Sequence
DKCSCPP CSIPnSi
Pn columns (80 or 132).
DECCOLM Sot: CSI ? 3 h
■ . . ■. .' . . ■ .-. 132 columns. '. ■ \. ■ ' ■ •.• '■•. ' ■ .
Reset: CSI ?31
80 columns. ID)
DECSLPP CSTPnt
Pn lines por page.
The number of pages depend on how many
you use.
Pn Dual Single
24 3 pages pages
.Ui :-!
DECOM Set:CSI?6h
Move within margins.
Reset: CSI ? 6 I
Move outside margins. |D)
DECSTBM CSIPtjPbr
Hr = top line.
Pb = bottom line.
112 PAGE MEMORY
Table 6-2 Sequences for Moving Through Page Memory
Name
Mnemonic
■ Sequence
New Cursor Position*
Next page
NP
CSI Pn LI
Home.
Preceding page
PP
CSI Pn V
Home.
Page position
absolute
PPA
CSI Pn sp P
Same as old page.
Page position
backward
PPB
CSI Pn sp R
Same as old page.
Page position
relative
PPR
CSI Pn sp Q
Same as old page.
* Pn = the number of pages to move, except for PPA.
For PPA. Pn = the actual page number.
PAGE MEMORY 113
7
SETTING VISUAL CHARACTER
AND LINE ATTRIBUTES
Setting Visual Character Attributes, 114
Select Graphic Rendition (SGR), 115
Setting Line Attributes, 116
Single-Width, Single Height Line (DECSWL), 116
Double-Width, Single Height Line (DECDWL), 116
Double-Width, Double Height Line (DECDHL), 116
Summary, 117
This chapter describes how to select visual attributes for display characters.
Visual character attributes change the way characters appear on the screen,
without changing the actual characters. For example, the bold character attri-
bute makes a character appear heavier on the screen. You can also select the
visual attributes for a complete display line on the screen.
SETTING VISUAL CHARACTER ATTRIBUTES
This section describes how to select, change, and reverse visual character attri-
butes. You can set the following attributes.
bold
underline
blink
negative image (dark character on a light background)
invisible
114
Select Graphic Rendition (SGR)
This control function selects one or more character attributes at the same time.
Default: Clear all attributes.
CSI Ps
9/11 3/?
; Ps
3/11 3/?
m
6/13
where
Ps is a number representing a certain visual attribute. You can use more
than one Ps value to select different character attributes. Table 7-1 lists
Ps values and the attributes they select.
Default: Ps = (clears all attributes).
Table 7-1
Ps
1
4
5
7
8 ' '
22
24
25
27
28
Examples
Visual Character Attribute Values
Attribute
All attributes off
Bold
Underline
Blinking
Negative image
Invisible
Bold off
Underline off
Blinking off
Negative image off
Invisible off
Mndu
VTlOOor VT300
VT30G only
When you select more than one attribute in an SGR sequence, they
are executed in order. For example, you can use the following se-
quence to display text that is bold, blinking, and underlined.
CSI ; 1 ; 5 ; 4 m
The following sequence displays the negative image of text.
CSI 7 m
SETTING VISUAL CHARACTER AND LINE ATTRIBUTES 115
Notes on SGR
• After you select an attribute, the terminal applies that attribute to
all new characters received. If you move characters by scrolling, the
attributes move with the characters.
• If you display control characters, the terminal ignores the bold attri-
bute for displayed control characters. See "Display Controls Mode"
at the end of Chapter 2.
SETTING LINE ATTRIBUTES
Line attributes are display features that affect the way a line of characters ap-
pears on the screen. For example, the double-width, single height line
(DECDWL) attribute makes a line of characters appear twice as wide as a nor-
mal line of characters. This section describes how to select line attributes.
Single-Width, Single-Height Line (DECSWL)
This control function makes the line with the cursor single-width and single-
height. This line attribute is the standard for all new lines on the screen.
ESC # 5
1/11 2/3 3/5
Double-Width, Single-Height Line (DECDWL)
This control function makes the line with the cursor double-width and single-
height. If the line was single-width and single-height, all characters to the right
of the screen's center are lost.
ESC # 6
1/11 2/3 3/6
Double-Width, Double-Height Line (DECDHL)
These two control functions make the line with the cursor the top or bottom
half of a double-height, double-width line. You must use these sequences in
pairs on adjacent lines. In other words, the same display characters must ap-
pear in the same positions on both lines to form double-height characters. If
the line was single-width and single-height, all characters to the right of the
screen center are lost.
Top Half Bottom Half
ESC # 3 ESC # 4
1/11 2/3 3/3 1/11 2/3 3/4
116 SETTING VISUAL CHARACTER AND LINE ATTRIBUTES
Example
The following sequences make the phrase "VT300 Video Terminal" double-
height and double-width.
ESC#3 VT300 Video Terminal
ESC#4 VT300 Video Terminal
SUMMARY
Table 7-2 lists the control functions described in this chapter.
Table 7-2 Character and ! .inc. Attribute S*:q!MiBr.es
Name
Mnemonic
.' Sequence
Select graphic
rendition
SGR
CSI Ps...Ps m
Ps = character attribute value(s)
(Table 7-1)
Single-width,
single-height line
DECSWL
ESC » 5
Double-width,
single-height line
DECDWL
ESC # 6
Double-width,
double-height line
DECDHL
ESC # 3 (top half)
ESC t 4 (bottom half)
SETTING VISUAL CHARACTER AND LINE ATTRIBUTES 117
8
EDITING
AND
CHARACTER PROTECTION
Editing, 119
Erasure Mode (ERM), 119
Insert/Replace Mode (IRM), 119
Delete Line (DL), 120
Insert Line (IL), 121
Delete Character (DCH), 121
Insert Character (ICH), 122
Erase in Display (ED), 122
Erase in Line (EL), 123
Erase Character (ECH), 124
Selective Erase in Display (DECSED), 124
Selective Erase in Line (DECSEL), 125
Character Protection, 126
Independent Protection, 126
How It Differs from Visual Attribute Protection, 127
Select Character Protection Attribute (DECSCA), 127
Start Protected Area (SPA) and End Protected Area (EPA), 128
Visual Attribute Protection, 129
How It Differs From Independent Protection, 129
Protected Fields Attributes (DECPRO), 129
Summary, 131
You use editing control functions to insert, delete, and erase characters and
lines of characters at the cursor position. You use character protection control
functions to protect characters in the terminal's page memory. Protected char-
acters cannot be changed, erased, or moved by certain editing control functions.
This chapter describes how to edit and protect characters in page memory.
118
EDITING
This section describes the editing control functions available in the VT300. The
cursor does not move when you use these functions.
Erasure Mode (ERM)
This control function determines whether the erasure functions can edit pro-
tected characters. Table 8-1 lists the functions that ERM affects. ERM also
affects the independent style of character protection. See "Character
Protection" later in this chapter for information on protection styles.
Default: Unprotected.
Mode Sequence
Set
(All)
CSI
9/11
6
3/6
h
6/8
Reset
(Unprotected)
CSI
9/11
6
3/6
1
6/12
Notes on ERM
Action
Erasure functions (ED, EL,
and ECH) can affect all charac-
ters, protected and unprotected.
Erasure functions (ED, EL,
and ECH) can affect only
unprotected characters.
• ERM does not affect the selective erase functions (DECSED,
DECSEL). DECSED and DECSEL can never erase protected char-
acters, regardless of the setting of ERM.
• In edit mode (DECEDM): ERM also affects the following editing
functions: DL, IL, DCH, ICH. See Chapter 9.
Table 8-1 Control Functions Affected by Character Protection
Always ■
Erase character (ECH)
Erase in line (EL) i V; '■■■
Erase in display (ED)
If Edit Mode (DECEDM) Is Set
Insert character (ICH)
Insert line (ID
Delete character (DCH)
Delete line (DL)
Insert/Replace Mode (IRM)
This control function selects how the terminal adds characters to page memory.
The terminal always adds new characters at the cursor position.
EDITING AND CHARACTER PROTECTION 119
Default: Replace.
Mode
Sequence
Action
Set
CSI 4 h
Selects insert mode.
(Insert)
9/11 3/4 6/8
New characters move charac
ters in page memory to the
right.
Characters moved past the
right page border are lost from
page memory.
Reset
CSI 4 1
Selects replace mode.
(Replace)
9/11 3/4 6/12
New characters replace the
character at the cursor posi
tion.
Notes on IRM
If erasure mode (ERM) is reset, text moved into a protected charac-
ter field is lost.
Delete Line (DL)
This control function deletes one or more lines in the scrolling region, starting
with the line that has the cursor.
CSI Pn M
9/11 3/? 4/13
where
Pn is the number of lines to delete.
Default: Pn = 1.
As lines are deleted, lines below the cursor and in the scrolling region move up.
Blank lines with no visual attributes are added at the bottom of the scrolling
region. If Pn is greater than the number of lines remaining on the page, DL
deletes only the remaining lines. DL has no effect outside the scrolling
margins.
120 EDITING AND CHARACTER PROTECTION
Notes on DL
• In edit mode (DECEDM): If erasure mode (ERM) is reset, DL can-
not delete lines that have protected characters. As lines are deleted,
the area moved up is bounded by the bottom of the scrolling region,
or by the next line with a protected character field. See Chapter 9.
Insert Line (IL)
This control function inserts one or more blank lines, starting at the cursor.
CSI Pn L
9/11 3/? 4/12
where
Pn is the number of lines to insert.
Default: Pn = 1
As lines are inserted, lines below the cursor and in the scrolling region move
down. Lines scrolled off the page are lost. IL has no effect outside the page
margins.
Notes on IL
• In edit mode (DECEDM): If erasure mode (ERM) is reset, lines that
move down into a line with a protected character field are lost. See
Chapter 9.
Delete Character (DCH)
This control function deletes one or more characters, from the cursor position
to the right.
CSI Pn P
9/11 3/? 5/0
where
Pn is the number of characters to delete. If Pn is greater than the number
of characters remaining on the line, DCH only deletes the remaining
characters.
Default: Pn = 1.
As characters are deleted, characters to the right of the cursor move left.
Character attributes move with the characters. The spaces created at the end
of the line have all attributes off.
EDITING AND CHARACTER PROTECTION 121
Notes on DCH
In edit mode (DECEDM)
— If erasure mode (ERM) is reset, DCH cannot delete protected
characters.
— If characters are protected by the DECPRO function, DCH can-
not delete protected characters. See Chapter 9.
Insert Character (ICH)
This control function inserts one or more space (SP) characters, starting at the
cursor position.
Available in: VT300 mode only
CSI Pn @
9/11 3/? 4/0
where
Pn is the number of characters to insert.
Default: Pn = 1.
The ICH sequence inserts Pn blank characters with the normal character attri-
bute. The cursor remains at the beginning of the blank characters. Text to the
right of the cursor moves right. Characters scrolled off the page are lost.
Notes on ICH
• In edit mode (DECEDM): If erasure mode (ERM) is reset, text
moved into a protected character field is lost. See Chapter 9.
Erase in Display (ED)
This control function erases characters from part or all of the display. When
you erase complete lines, they become single-height and single-width, with all
visual character attributes cleared. ED works inside or outside the current
margins
CSI Ps J
9/11 3/? 4/10
122 EDITING AND CHARACTER PROTECTION
where
Ps represents the amount of the display to erase, as follows.
Ps Area Erased
(default) From the cursor through the end of the display
1 From the beginning of the display through the cursor
2 The complete display
PROGRAMMING TIP: Use a Ps value of 2 to erase the complete display in a
fast, efficient manner.
Notes on ED
• If erasure mode (ERM) is reset, ED cannot erase protected charac-
ter positions.
Erase in Line (EL)
This control function erases characters on the line that has the cursor. EL
clears all character attributes from erased character positions. EL works inside
or outside the current margins.
CSI Ps K
9/11 3/? 4/11
where
Ps represents the section of the line to erase, as follows.
Ps Section Erased
(default) From the cursor through the end of the line
1 From the beginning of the line through the cursor
2 The complete line
Notes on EL
If erasure mode (ERM) is reset, EL cannot erase protected
characters.
EDITING AND CHARACTER PROTECTION 123
Erase Character (ECH)
This control function erases one or more characters, from the cursor position to
the right. ECH clears character attributes from erased character positions.
ECH works inside or outside the current margins.
Available in: VT300 mode only
CSI Pn X
9/11 3/? 5/8
where
Pn is the number of characters to erase. A Pn value of or 1 erases one
character.
Default: Pn = 1.
Notes on ECH
• If erasure mode (ERM) is reset, ECH cannot erase protected
characters.
Selective Erase in Display (DECSED)
This control function erases some or all of the erasable characters in the dis-
play. DECSED can only erase characters defined as erasable by the DECSCA,
SPA, or EPA control functions. See "Character Protection" later in this chap-
ter for details. DECSED works inside or outside the scrolling margins, except
in edit mode (DECEDM). In edit mode, DECSED cannot erase characters out-
side the scrolling margins.
Available in: VT300 mode only
CSI ? Ps J
9/11 3/15 3/? 4/10
where
Ps represents the area of the display to erase, as follows.
Ps Area Erased
(default) From the cursor through the end of the display
1 From the beginning of the display through the cursor
2 The complete display
124 EDITING AND CHARACTER PROTECTION
Notes on DECSED
• DECSED is not affected by erasure mode (ERM).
• DECSED does not affect visual character attributes set by the se-
lect graphic rendition (SGR) function, or selection attributes set with
SSA or ESA functions (Chapter 9).
• DECSED provides full compatibility with applications that use the
VT220 selective erase feature.
Selective Erase in Line (DECSEL)
This control function erases some or all of the erasable characters in a single
line of text. DECSEL erases only those characters defined as erasable by the
DECSCA, SPA, or EPA control functions. See "Character Protection" later in
this chapter for details. DECSEL works inside or outside the scrolling margins,
except in edit mode (DECEDM). In edit mode, DECSEL cannot erase charac-
ters outside the scrolling margins.
Available in: VT300 mode only
CSI ? Ps K
9/11 3/15 3/? 4/11
where
Ps represents the section of the line to erase, as follows.
Ps Section Erased
(default) From the cursor through the end of the line
1 From the beginning of the line through the cursor
2 The complete line
Notes on DECSEL
• DECSEL is not affected by erasure mode (ERM).
• DECSEL does not affect visual character attributes set by the select
graphic rendition (SGR) function.
• DECSEL provides full compatibility with applications that use the
VT220 selective erase feature.
EDITING AND CHARACTER PROTECTION 125
CHARACTER PROTECTION
You can protect character positions in the terminal's page memory. Protected
characters cannot be changed, erased, or moved by certain editing control func-
tions (such as ED, EL, or ECH).
There are two styles of character protection available.
• Independent protection
• Visual attribute protection
You should use only one style of protection at a time. The two styles do not
protect characters in the same way. To avoid confusion, Digital recommends
that you use only one style of protection for each text form you design.
The following sections describe each style of character protection and list the
editing control functions affected.
PROGRAMMING TIP: Digital recommends that new applications use indepen-
dent protection. Visual attribute protection is only provided for strict compati-
bility with Digital's VT131 terminal.
INDEPENDENT PROTECTION
This style of character protection lets you protect all the characters in an area
of page memory, independent of their visual attributes (such as bold and under-
line). When you use independent protection, the following control functions can-
not change, erase, or move the protected characters.
Erase in display (ED)
Erase in line (EL)
Erase character (ECH)
In addition, if you set edit mode (DECEDM), the following control functions
cannot change, delete, or move protected characters.
Insert line (IL)
Insert character (ICH)
Delete line (DL)
Delete character (DCH)
See Chapter 9 for details on edit mode.
126 EDITING AND CHARACTER PROTECTION
How It Differs from Visual Attribute Protection
There are three basic differences between independent protection and visual
attribute protection.
• Independent protection lets you protect characters independent of
their visual character attributes. Visual attribute protection applies to
characters with the same visual character attribute.
• You can use independent protection in any operating mode. You can
use visual attribute protection only in edit mode (Chapter 9).
• Independent protection depends on the current setting of erasure
mode (ERM), visual attribute protection does not.
ERM determines whether or not independently protected characters
can be changed, erased, or moved.
ERM set All characters can be changed, erased, or moved,
regardless of protection.
ERM reset Only unprotected characters can be changed,
erased, or moved (using the erasure control
functions).
See "Erasure Mode (ERM)" earlier in this chapter for details. Table
8-1 describes how erasure mode (ERM) affects protected characters.
For more details, see "Visual Attribute Protection" later in this chapter.
NOTE: You should use only one style of protection at a time. The two styles of
protection (independent and visual attribute) do not protect characters in the
same way. To avoid confusion, use only one style of protection for each text
form you design.
PROGRAMMING TIP: Digital recommends that new applications use indepen-
dent protection. Visual attribute protection is only provided for strict compati-
bility with Digital's VT131 terminal.
The following sections describe the control functions you use to define areas of
page memory as independently protected.
Select Character Protection Attribute (DECSCA)
This control function defines successive characters written to page memory as
protected or unprotected. The erasure control functions (ED, EL, or ECH) can-
not erase protected characters.
EDITING AND CHARACTER PROTECTION 127
Available in: VT300 mode only
CSI Ps
9/11 3/?
2/2
q
7/1
where
Ps defines all following characters as protected or unprotected.
Ps
(default)
1
2
Notes on DECSCA
Meaning
Not protected.
Protected.
Not protected. Same as default setting.
• DECSCA does not affect visual character attributes set by the select
graphic rendition (SGR) function.
• If erasure mode (ERM) is set, you can erase protected characters by
using the ED, EL, or ECH functions.
Start Protected Area (SPA) and End Protected Area (EPA)
These control functions define the beginning and end of a protected area in
page memory. The erasure control functions (ED, EL, and ECH) cannot change
protected areas.
You can represent SPA or EPA as an 8-bit control character, or as a 7-bit
escape sequence.
Action
Defines the cursor position
as the beginning of a series
of protected characters.
Defines the cursor position
as the end of a series of
protected characters.
Notes on SPA and EPA
• The terminal ignores any EPA received before an SPA.
• If SPA is not followed by an EPA on the same page, SPA has no
effect on the page.
Name
8-Bit
7-Bit
Start of
SPA
ESC
V
protected
9/6
1/11
5/6
area (SPA)
End of
EPA
ESC
W
protected
9/7
1/11
5/7
area (EPA)
128 EDITING AND CHARACTER PROTECTION
VISUAL ATTRIBUTE PROTECTION
This style of character protection lets you protect characters with the same
visual attribute in an area of page memory. When you use visual attribute pro-
tection, the following control functions cannot change, erase, or move protected
characters.
Insert character (ICH) Erase character (ECH)
Insert line (IL) Erase in line (EL)
Delete character (DCH) Erase in display (ED)
Delete line (DL)
How It Differs from Independent Protection
There are three basic differences between visual attribute protection and inde-
pendent protection.
• Visual attribute protection applies to characters with the same visual
character attribute. For example, you can protect all characters with
the bold attribute or underline attribute. Independent protection is
independent of visual attributes.
• Visual attribute protection is only available in edit mode (DECEDM).
You can use independent protection in all operating modes.
• Visual attribute protection is not affected by erasure mode (ERM).
Independent protection is affected.
NOTE: You should use only one style of protection at a time. The two styles of
protection (independent and visual attribute) do not protect characters in the
same way. To avoid confusion, use only one style of protection for each text
form you design.
PROGRAMMING TIP: Digital recommends that new applications use indepen-
dent protection. Visual attribute protection is only provided for strict compati-
bility with Digital's VT131 terminal.
You use the DECPRO control function to protect characters based on their vi-
sual attributes.
Protected Fields Attributes (DECPRO)
This control function selects character protection based on visual attributes.
Available in: edit mode (DECEDM)
CSI Ps ... Psn }
9/11 3/? ... 3/? 7/13
EDITING AND CHARACTER PROTECTION 129
where
Ps defines characters with a certain character attribute as protected or
unprotected. You can select more than one attribute.
Characters Affected
Characters with no attribute (normal)
Bold characters
Underlined characters
Blinking characters
Negative image characters
Invisible characters
Bold characters
Underlined characters
Blinking characters
Negative image characters
Invisible characters
All characters
When you select more than one attribute in a DECPRO sequence, any charac-
ter position with one or more of the selected attributes is protected.
Ps
Protection
On
1
On
4
On
5
On
7
On
8
On
22
Off
24
Off
25
Off
27
Off
28
Off
254
Off
Examples
The following sequence protects characters with the bold attribute,
blinking attribute, or both attributes.
CSI ; 1 ; 5 }
The following sequence protects only characters with the underline
attribute.
CSI 4 }
Notes on DECPRO
DECPRO does not change the appearance of characters (their visual
attributes). DECPRO only changes the protection of characters for
editing.
DECPRO is only available in edit mode (DECEDM). You can use
both styles of protection (independent or visual attribute) in edit
mode.
130 EDITING AND CHARACTER PROTECTION
SUMMARY
Tables 8-2 and 8-3 list the control functions described in this chapter.
Tubie 8-2 Editing Setfuewtes
Name
Mnemonic
.■■ Sequence
Erasure mode
ERM
Set: CSI 6 li
You can edit all characters.
Reset: CSI G 1
You can m^y edit unprotected characters
(D)
Insert/
IRM
Set: CSI 4 h
replace.
Insert characters.
mode
Reset: CSI 4 I
Replace characters.
Delete line
DL
CSI Pn M
.. Pn lines.
Insert line
IL
CSI Pn L
Pn lines.
Delete
DCH
CSI Pn P
character
Pn characters.
Insert:'-;'.'
ICH
CSI Pn @
character
Pn characters.
ID) = default.
EDITING AND CHARACTER PROTECTION 131
Table 8-2
Ed
itiug Sequences
(Cont) ■'■
Name
Mnemonic
Sequence
Erase
ED
CSI Ps J
in display
Ps = 0. cursor to end. (D)
Ps = 1 . beginning to cursor
Ps = 2. complete display.
Erase in line
EL
CSI Ps K
Erase
ECH
character*
Selective
DECSED
erase
in display*
Selective
DECSEL
erase
in line*
Ps = 0. cursor to end. |D)
Ps = 1. beginning to cursor.
Ps = 2. complete line.
CSI Pn X
Pn characters.
CSI ? Ps J
Ps = 0. cursor to end. (D)
Ps = 1 , beginning to cursor.
Ps = 2. complete display.
CSI ? Ps K
Ps = 0, cursor to end. (Dl
Ps = 1. beginning to cursor.
Ps = 2, complete line.
ID) = default.
* Available in VT300 mode only.
132 EDITING AND CHARACTER PROTECTION
Table 8-3 Character Protection Sequences
Name Mnemonic Sequence
Independent Protection
Select character DECSCA CSI Ps " q
attribute* Ps = or 2, unprotected. (D)
Ps = 1, protected.
Start protected SPA 8-bit: SPA
area 7-bit: ESC V
End protected EPA 8-bit: EPA
area 7-bit: ESC W
Visual Attribute Protection (For Local Editing Only)
Protected fields DECPRO CSI Ps }
attribute Ps = character attribute value.
See "Setting Visual Character Attributes."
* Available in VT300 mode only.
EDITING AND CHARACTER PROTECTION 133
9
LOCAL EDITING
How Local Editing Works, 135
What Control Functions Do You Use?, 135
Selecting Edit Mode, 136
Edit Mode (DECEDM), 136
Edit Key Execution Mode (DECEKEM), 136
Defining the Size of the Character Block. 137
Line Transmit Mode (DECLTM), 138
Transmit Termination Mode (TTM), 139
VT131 Transmit Mode (DEC131TM), 140
Selecting the Characters to Send, 141
Guarded Area Transfer Mode (GATM), 141
Selected Area Transfer Mode (SATM), 142
Multiple Area Transfer Mode (MATM), 143
Defining Selected Areas, 143
Start Selected Area (SSA) and End Selected Area (ESA), 143
End-of-Block and Unused Space Characters, 144
Set Transmit Termination Character (DECTTC), 144
Transmit Line Termination Characters (DECTLTC), 146
Space Compression Mode (DECSCFDM), 147
Sending Edited Data to the Host, 148
Transmit Execution Mode (DECTEM), 148
Set Transmit State (STS), 149
Transmit Mode (DECXMIT), 149
Block Transmission Examples, 149
Character Sets and Block Transmission, 153
Block Transmission in an 8-Bit Environment, 153
Block Transmission in an 7-Bit Environment, 154
Summary, 156
134
HOW LOCAL EDITING WORKS
The VT300 can operate as an interactive or editing terminal. As an interactive
terminal, the VT300 immediately sends each character you type to the host
computer. Host software must perform any editing functions.
As an editing terminal, the VT300 does not send your typed characters imme-
diately to the host. Instead, the terminal stores the characters in its page
memory and displays them on the screen. You can edit the displayed charac-
ters, then send them to the host in a single block. The terminal performs your
editing functions locally.
NOTE: Local editing requires host software support.
By using the local editing feature, applications can free the host from editing
tasks. You can edit as much data as you can store in page memory. You send
the block of edited data to the host by using a control function. The terminal
locks the keyboard until the transmission is complete.
What Control Functions Do You Use?
In edit mode, you can use the erasure, deletion, and insertion control functions
described in Chapter 8. You can also use either style of character protection,
independent or visual attribute.
The character protection feature lets you design text forms that cannot be
changed or overwritten. In edit mode, character protection also depends on the
setting of erasure mode (ERM).
• If ERM is set, all characters can be changed, erased, and moved,
regardless of protection.
• If ERM is reset, only unprotected characters can be changed,
erased, and moved. The following control functions will not affect
protected areas in page memory.
Insert line (IL) Erase in display (ED)
Delete line (DL) Erase in line (EL)
Insert character (ICH) Erase character (ECH)
Delete character (DCH)
This chapter describes how to select local editing and send edited data to the
host. The chapter also describes how to select what areas of page memory you
send to the host. For example, you may not want to send protected areas to
the host.
LOCAL EDITING 135
SELECTING EDIT MODE
There are two ways to select edit mode. Applications can use the edit mode
(DECEDM) sequence, or you can press Shift-EDIT.
Edit Mode (DECEDM)
This control function selects edit mode or interactive mode. This function deter-
mines when the terminal sends data to the host.
Default: Interactive mode
Mode
Sequence
Set
CSI ? 1 h
(Edit mode)
9/11 3/15 3/1 3/0 6/8
Reset
(Interactive
mode)
CSI ? 10 1
9/11 3/15 3/1 3/0 6/12
Action
Selects edit mode. (Turns
on the edit mode indicator
on the status line.) The
terminal stores all typed
characters in page memory,
for local editing. After
you edit the stored data,
you can send it in a block
to the host.
Selects interactive mode.
(Turns off the edit mode
indicator.) The terminal
immediately sends typed
characters to the host.
Edit Key Execution Mode (DECEKEM)
You can switch between edit mode and interactive mode by pressing Shift-
EDIT. This control function determines if the terminal switches modes immedi-
ately or when the application decides.
Default: Immediate
Mode Sequence
Set
(Immediate)
CSI ? 16 h
9/11 3/15 3/1 3/6 6/8
Action
When you press Shift-EDIT,
the terminal immediately
switches between
interactive and edit
modes.
136 LOCAL EDITING
Reset
CSI ? 16 1
(Deferred)
9/11 3/15 3/1 3/6 6/12
When you press Shift-EDIT,
the terminal sends DECEDM
(set or reset) to the host
to switch modes. Then the
terminal waits for the
host to return DECEDM to
change the terminal's
current mode.
DEFINING THE SIZE OF THE CHARACTER BLOCK
In edit mode, you can select which data the terminal sends to the host. The
amount of data sent depends on two factors.
• the size of the character block you define
• the areas of text you select as eligible to send
This section describes how to define the size of the character block. The next
section describes how to select areas of page memory as eligible to send.
You can send up to a page of data at one time. You can use three control
functions to define the size of the character block sent to the host.
Line transmit mode (DECLTM)
Transmit termination mode (TTM)
VT131 transmit mode (DEC131TM)
Table 9-1 lists the block sizes you can select with these functions. You can
select from three different block sizes.
VT131 partial page
Includes the text on the current page between the partial page marker and
the cursor. The partial page marker does not appear on the screen. The
terminal automatically places the marker at the position of the last charac-
ter sent. If there is no marker, or the marker is after the cursor, the ter-
minal sends all eligible characters between the top margin and the cursor.
ANSI partial page
Includes the text on the current page from the beginning of a selected
area to the cursor. A selected area is a block of text that is selected as
eligible to send to the host.
LOCAL EDITING 137
Scrolling region
Includes the text of the current page that is inside the margins.
Table 9-1 Defining the Character Block Size for Transmission
■Line
TraHSmlt
VT131
Transmit
Termination
Transmit
Mode
Mode
Mode
Block Size
(DECLTM)
(TTM)
(DEC131TM)
Line
Set.
—
—
VT131 partial page
Reset
Reset
Set
ANSI partial page fy. - /:■':';'.
Reset
Reset
' Reset ■
Scrolling region .
Reset
Set
_
Line Transmit Mode (DECLTM)
This control function lets you select one of two options for the size of the char-
acter block.
• a line of characters
• a full or partial page
To select a scrolling region or partial page, you must also use transmit termina-
tion mode (TTM) and VT131 transmit mode (DEC131TM).
In a line transmission, the terminal sends eligible characters from the line with
the cursor. These characters are followed by any end-of-line characters and end-
of-block characters. To start a line transmission, you can press the Return or
Enter key.
If you press Return to start a line transmission, the cursor moves to the left
page border of the active line. If you press Enter to start a line transmission,
the cursor does not initially move.
If line feed/new line mode is set, the cursor moves to the first unprotected field
in the next line.
If the cursor is at the end of scrolling region, the cursor moves to the first
unprotected field on the current line.
DECLTM applies only in edit mode (DECEDM).
138 LOCAL EDITING
Default: Page of characters
Mode Sequence
Action
Set
(Line)
CSI
9/11
1
3/15
1
3/1
1 h
3/1 6/8
Reset
(Page)
CSI
9/11
?
3/15
1
3/1
1 1
3/1 6/12
Selects line transmission.
Selects full or partial page
block transmission, depending
on the settings of transmit
termination mode (TTM) and
VT131 transmit mode (VT131TM).
Notes on DECLTM
• When DECLTM is reset (page), TTM and VT131TM let you select
from three block sizes: VT131 partial page, ANSI partial page, or
the scrolling region.
Transmit Termination Mode (TTM)
If line transmit mode (DECLTM) is reset (page), transmit termination mode
(TTM) and VT131 transmit mode (DEC131TM) define the size of the character
block. TTM determines whether the terminal includes the cursor position as
part of the criteria that ends a block transmission.
Default: Scrolling region
Mode Sequence Action
Set
(Scrolling
region)
Reset
(Partial
page)
CSI 1 6 h
9/11 3/1 3/6 6/8
CSI
9/11
1 6 1
3/1 3/6 6/12
The terminal sends the scrolling
region.
The terminal sends a VT131 or
or ANSI partial page, based on
VT131 transmit mode (DEC131TM).
DEC131TM Selects
Set
Reset
VT131 partial page
ANSI partial page
LOCAL EDITING 139
Notes on TTM
• When you select a VT131 partial page, the terminal sends all eligible
characters between the partial page marker and the cursor. If there
is no marker, or the marker is after the cursor, the terminal sends
all eligible characters between the top margin and the cursor.
The partial page marker does not appear on the screen. The termi-
nal automatically places the marker at the position of the last char-
acter sent.
You use this setting for compatibility with the VT131 terminal.
• When you select an ANSI partial page, the terminal sends all eligi-
ble characters from the beginning of a selected area to the cursor.
VT131 Transmit Mode (DEC131TM)
If line transmit mode (DECLTM) is reset (page), DEC131TM and transmit ter-
mination mode (TTM) together define the size of the character block the termi-
nal can send to the host. You cannot use DEC131TM and TTM separately.
Table 9-1 shows how the terminal determines the size of the character block to
send. Table 9-2 shows how the terminal determines which characters are eligi-
ble to send.
Default: ANSI
Mode
Sequence
Set
(VT131)
CSI
9/11
3/15
5
3/5
3
3/3
h
6/8
Reset
(ANSI)
CSI
9/11
?
3/15
5
3/5
3
3/3
1
6/12
Action
The terminal works like a
VT131 terminal.
The terminal works according
to ANSI rules.
140 LOCAL EDITING
Table 9-2 Selecting Character Fields for Transmission
Fields Selected
All fields
Unprotected
fields only
Selected fields
only
Selected field
with cursor only
Unprotected
and selected fields
Unprotected fields
and selected field
with cursor
SELECTING THE CHARACTERS TO SEND
There are five control functions that select which characters the terminal can
send to the host.
Guarded Area
Selected Area
Multiple Area
Transfer
Mode
Transfer Mode
Transfer Mode
(GATM)
(SATM)
(MATM)
Set
Set
Not available
Reset
Set
Not available
Set
Reset
Set
Set
Reset
Reset
Reset
Reset
Set
Reset
Reset
Reset
Function
Guarded area transfer mode (GATM)
Selected area transfer mode (SATM)
Mui Jple area transfer mode (MATM)
Start selected area (SSA)
End selected area (ESA)
Use
Send protected areas.
Send one or all selected areas.
Define a selected area.
The following sections describe each control function. Table 9-2 shows how
these functions select which characters the terminal sends. Table 9-1 shows
how other functions select the size of the character block to send.
Guarded Area Transfer Mode (GATM)
This control function selects whether the terminal can send all characters or
only unprotected characters to the host. See "Character Protection" in Chapter
8 for information on the two styles of character protection available.
LOCAL EDITING 141
Default: All characters
Mode
Set
(All)
Reset
(Unprotected)
Sequence
CSI 1 h
9/11 3/1 6/8
CSI 1 I
9/11 3/1 6/12
Action
Selects all characters.
During block transmission,
the terminal can send all
protected and unprotected
characters to the host.
Selects unprotected
characters. During a block
transmission, the terminal
can send only unprotected
characters to the host.
Notes on GATM
• When GATM is reset (unprotected), the terminal sends a record sep-
arator (RS, 1/14) to the host in place of a protected field. The termi-
nal sends a space character (SP, 2/0) to a printer in place of a
protected field.
Selected Area Transfer Mode (SATM)
This control function determines whether the terminal can send all characters
or only selected characters to the host. Selected characters are characters de-
fined as eligible to send to the host.
You can define selected areas on the current page with the start selected area
(SSA) and end selected area (ESA) control functions.
Default: All characters
Mode
Sequence
Action
Set
(All)
CSI
9/11
1
3/1
7
3/7
h
6/8
Selects all characters.
The terminal can send selected
and unselected characters
on the current page to the
host.
Reset
(Selected
only)
CSI
9/11
1
3/1
7
3/7
1
6/12
Selects only selected
characters. The terminal
142
LOCAL EDITING
can only send selected
characters on the current
page to the host.
Multiple Area Transfer Mode (MATM)
This control function determines what selected character areas the terminal can
send to the host. MATM only works when selected area transfer mode (SATM)
is reset.
Default: All selected areas
Mode
Sequence
Set
(All)
CSI
9/11
1
3/1
5
3/5
h
6/8
Reset
(One area)
CSI
9/11
1
3/1
5
3/5
1
6/12
Notes on MATM
Action
The terminal can send all
selected areas on the page to
the host.
Selects one area. The terminal
can send only the selected area
with the cursor.
• If MATM is reset (one area) and the cursor is not in a selected field,
the cursor moves to the next selected field.
Defining Selected Areas
The next two control functions select what characters are eligible to send to
the host. Eligible characters are called selected characters.
Start Selected Area (SSA) and End Selected Area (ESA) - These two control
functions select which characters on the current page the terminal can send to
the host. SSA and ESA only work when selected area transfer mode (SATM) is
reset.
SSA and ESA are 8-bit CI control characters. You can also code SSA and
ESA as 7-bit escape sequences.
Name
8-Bit
7-Bit Equivalent
Action
Start selected
SSA
ESC F
Marks the cursor
area (SSA)
8/6
1/11 4/6
position as the first
of a string of
LOCAL EDITING 143
character positions the
terminal can send to
the host.
End selected
ESA
ESC
G
Defines the cursor
area (ESA)
8/7
1/11
4/7
position as the last
of a string of
character fields the
terminal can send to
host.
Notes on SSA and ESA
• If the terminal receives ESA before SSA, the terminal ignores ESA.
• If SSA is not followed by ESA on the same page, the SSA has no
effect on that page. Selected areas must always end with ESA.
• Selected areas cannot be changed by the ED, EL, or ECH control
functions.
END-OF-BLOCK AND UNUSED SPACE CHARACTERS
These control functions affect the way the terminal sends end-of-block, end-of-
line, and space characters to the host in edit mode.
Set transmit termination
character (DECTTC)
Set transmit line
termination character
(DECTLTC)
Space compression mode
(DECSCFDM)
Selects one or more end-of-block
characters.
Selects one or more end-of-line
characters.
Determines whether or not to send
unused space characters.
Set Transmit Termination Character (DECTTC)
This control function lets you select a character to indicate the end of a block
transmission. You do not have to use an end-of-block character. The terminal
sends the end-of-block character to the host at the end of each block
transmission.
CSI Ps |
9/11 3/? 7/12
144 LOCAL EDITING
where
Ps represents the end-of-block character, as follows.
Ps
(default)
1
2
3
4
5
End-of-Block Character
No character (DECTTC disabled.
FF
form feed
0/12
ETX
end of text
0/3
EOT
end of transmission
0/4
CR
carriage return
0/13
DC3
XOFF
1/3
Extended Form
An extended form of the DECTTC control function lets you select a string of
characters to indicate the end of a block. This extended form uses decimal
codes to represent characters. You can use the extended form to send a control
function at the end of a block transmission, instead of a single character. You
can send a control sequence of up to six characters (Pnl through Pn5) at the
end of a block.
CSI ? Pnl
9/11 3/15 3/?
3/11
Pn6 |
3/? 7/12
where
Pnl through Pn6 are decimal codes for characters that you can define as
end-of-block characters. For example, the decimal code for the ESC (1/11)
character is 27. The code table in Chapter 2 lists decimal codes for charac-
ters. Any code value outside of the range of to 254 is ignored.
Example
Suppose you want to send the default code of the PF1 key on the numeric
keypad at the end of a block transmission. You could use the following
procedure.
LOCAL EDITING 145
1. The PF1 key sends the following default code.
ESC O P
1/11 4/15 5/0
You must translate each character in the sequence to decimal code.
2. Use the code table in Chapter 2 to find the decimal code for each
character.
ASCII characters: ESCO P
Decimal codes: 27 79 80
3. Now insert the decimal codes in the extended DECTTC sequence.
CSI ? 27 ; 79 ; 80 |
Transmit Line Termination Characters (DECTLTC)
This control function lets you select the character(s) that the terminal sends to
the host at the end of each line of transmitted data.
Default: Carriage return (CR) — decimal code 13
CSI ? Pnl ; ... Pn6 ' s
9/11 3/15 ** 3/11 ** 2/7 7/3
where
Pnl through Pn6 are decimal codes for characters that you can define as
end-of-line characters. The code table in Chapter 2 lists decimal codes for
characters. Any code value outside of the range of to 254 is ignored.
Example
Suppose you want to send the default code of the Do key on the top row of
function keys at the end of a block transmission. You could use the following
procedure.
1. The Do key sends the following default code.
CSI 2 9
9/11 3/2 3/9 7/14
146 LOCAL EDITING
You must translate each character in the sequence to decimal code.
Use the code table in Chapter 2 to find the decimal code for each
character.
Characters:
Decimal codes:
CSI 2 9 "
155 50 57 126
Now insert the decimal codes in the DECTLTC sequence.
CSI ? 155; 50; 57; 126 ' s
Space Compression Mode (DECSCFDM)
This control function determines whether the terminal sends space characters
(SP, 2/0) at the end of characters fields. If the terminal does not send spaces,
it uses the record separator character (RS, 1/14) to indicate the end of a field.
Default: Spaces
Mode Sequence
Set
(No spaces)
CSI ? 13 h
9/11 3/15 3/1 3/3 6/8
Reset
(Spaces)
CSI ? 13 1
9/11 3/15 3/1 3/3 6/12
Action
Selects space compression.
The terminal does not send
spaces characters at the end
of a character field.
All fields sent end with a
single record separator (RS)
character, except the last
field on a line. The last
field ends with the
end-of-block character defined
by the transmit termination
character (DECTTC) function.
Selects no space compression.
The terminal sends space
characters to the host at
the end of a character field.
The terminal sends characters
as they appear on the page.
LOCAL EDITING 147
SENDING EDITED DATA TO THE HOST
After you finish editing, you press the Enter key to send edited data to the
host. Transmit execution mode (DECTEM) determines when the terminal actu-
ally sends the data.
Transmit Execution Mode (DECTEM)
When you press Enter, this control function determines whether the terminal
sends data immediately or waits for the host's permission. DECTEM operates
only in edit mode (DECEDM).
Default: Immediate
Mode
Sequence
Action
Set CSI ? 1 4 h
(Immediate) 9/11 3/15 3/1 3/4 6/8
Reset CSI ? 14 1
(Deferred) 9/11 3/15 3/1 3/4 6/12
When you press Enter, the
terminal immediately sends
a block of characters to
the host.
When you press Enter, the
terminal sends a request
to the host, asking if the
host is ready to receive a
block of characters. Then
the terminal waits until
the host responds.
Notes on DECTEM
When DECTEM is reset, the terminal requests a block transmission
by sending the set transmit state (STS) sequence to the host. The
host must respond with the DECXMIT sequence.
If line transmit mode (DECLTM) is set, the Return key works like
the Enter key. That is, pressing Return sends a block of characters
to the host.
See Installing and Using the VT330/VT340 Video Terminal for more
information on sending characters to the host.
148 LOCAL EDITING
Set Transmit State (STS) — From Terminal
The terminal sends this escape sequence to the host to request a block trans-
mission. The terminal only sends STS when transmit execution mode
(DECTEM) is reset.
ESC S
1/11 5/3
Transmit (DECXMIT) — From Host
The host responds to a set transmit state (STS) sequence by sending a
DECXMIT sequence to the terminal. DECXMIT tells the terminal to send a
block of characters.
ESC 5
1/11 3/5
BLOCK TRANSMISSION EXAMPLES
This section shows examples of what data the terminal sends to the host in a
block transmission. The data sent depends on the settings of various local edit-
ing control functions.
Each example lists an initial set of conditions in effect. Then each example
shows what data the terminal sends when you press the Transmit key, based
on these conditions.
All the examples are based on the screen in Figure 9-1. This screen is not 24
lines by 80 columns. However, a full screen is not needed to illustrate block
transmission. For the examples in this section, consider the screen in Figure
9-1 to be a full page. The following conditions apply to this figure.
•
The asterisk * indicates the cursor position.
Character positions in columns 1 through 9 are defined as protected
from erasure or movement. These characters have their protection
attribute set.
Character positions in columns 10 through 39 on lines 13 through
15 are defined as eligible for transmission. These characters have
their selection attribute set.
The top and bottom scrolling margins are set at lines 13 and 15
respectively.
LOCAL EDITING 149
Name:
John Doe
Company:
General Technology Corp.
Part No:
VR201
Name:
Video Monitor*
Color:
Amber
10
11
12
13 <-
14
15 <-
-Top Margin
-Bottom Margin
13579111112222233333
135791357913579
Figure 9-1 Sending Data in Edit Mode
The following abbreviations are used for characters in the examples.
Character
Abbreviation
End-of-block
<EOB>
End-of-line
<EOL>
Record separator
<RS>
Example 1
The following conditions
are in effect.
DECLTM reset
Scrolling region
GATM
set
All characters
SATM
set
DECSCFDM
reset
Send spaces
When you press Transmit, the terminal sends the following data.
Part No:VR201
Name: Video Monitor
Color: Amber
<E0L>
<E0L>
<E0L><E0B>
150 LOCAL EDITING
Example 2
The following conditions are in effect.
DECLTM
reset
Scrolling region
TTM
set
DEC131TM
set
GATM
reset
Unprotected
SATM
characters in the
scrolling region
are selected for
for transmission.
DECSCFDM
reset
Send spaces
When you press Transmit, the terminal sends the following data.
VR201
Video Monitor
Amber
<E0L>
<EOL>
<E0LXE0B>
Example 3
The following conditions are in effect.
DECLTM
reset
Partial page
TTM
reset
DEC131TM
set
GATM
set
All characters
SATM
set
DECSCFDM
set
Do not send spaces
When you press Transmit, the terminal sends the following data.
Part No:<RS>VR20KE0L>
Name:<RS>Video Monitor<E0L>
LOCAL EDITING 151
Example 4
The following conditions are in effect.
Page
DECLTM
reset
TTM
set
DEC131TM
reset
GATM
set
SATM
reset
MATM
reset
Between active position and cursor
reset
reset
DECSCFDM set Do not send spaces
When you press Transmit, the terminal sends the following data.
Video Moni tor<E0LXE0B>
Example 5
The following conditions are in effect.
DECLTM
reset
Page
TTM
set
DEC131TM
reset
GATM
set
All characters
SATM
set
DECSCFDM
set
Do not send spaces
When you press Transmit, the terminal sends the following data.
Name :<RS>John Brown<E0L>
Company :<RS>General Technology Corp.<E0L>
<E0L>
Part No:<RS>VR20KE0L>
Name:<RS>Video Moni tor<EOL>
Color:<RS>Amber<EOL><EOB>
Example 6
The following conditions are in effect.
DECLTM
TTM
DEC131TM
set
Active line
152 LOCAL EDITING
GATM set All characters
SATM set
DECSCFDM reset Send spaces
When you press Transmit, the terminal sends the following data.
Name: Video Monitor <E0L><E0B>
CHARACTER SETS AND BLOCK TRANSMISSION
The terminal can send characters from several possible character sets during a
block transmission. The VT300 sends characters based on the following general
rules.
• If space compression mode (DECSCFDM) is reset, the terminal
sends unwritten character positions as SP (2/0).
• The terminal never sends characters from the control representation
(CRM) font.
• Characters that are in page memory, but not available in the charac-
ter sets in the in-use table, are sent as SUB (1/10). For example,
characters that are not in the current user-preferred supplemental
set, or unique NRC characters such as the Dutch florin are sent as
SUB.
The algorithm the terminal uses to send characters depends on whether the
terminal is operating in an 8-bit or 7-bit environment.
Block Transmission in an 8-Bit Environment
National replacement character set mode (DECNRCM) is reset, and the termi-
nal is in VT300 mode. The terminal selects the character set for each transmit-
ted character as follows.
NOTE; If the host communication line is set to 7 bits, data can be lost during
a block transmission. The host forces the eighth bit of all received characters
to 0. If the current host line is set to 7 bits, terminal cannot correctly send
8-bit characters in a block transmission.
1. At the beginning of a block transmission, the terminal assumes the
ASCII set is in GL and the user-preferred supplemental set is in
GR.
LOCAL EDITING 153
2. The VT300 sends ASCII graphic and SP characters with their
eighth bit set to 0. The VT300 never sends a designating sequence
for ASCII or space characters.
3. For characters that are not ASCII characters or spaces, the VT300
sends the appropriate G2 designating sequence for the character set
containing those characters (Chapter 5). Then the VT300 sends the
characters from that set.
The VT300 always sends the actual designating sequence for the de-
sired character set. This removes any ambiguity for applications that
need to know which character set is currently defined as the user-
preferred set (ISO Latin-1 or DEC Supplemental Graphic).
NOTE; If the application sends the ISO level 1 announcer at the
beginning of execution, the VT300 sends the appropriate Gl desig-
nating sequence.
4. If the same character is in more than one character set, the VT300
uses the following priority system.
— ASCII
— User-preferred supplemental
— DEC Technical
— DEC Special Graphic
After the VT300 selects the appropriate character set, the VT300
sends the designating sequence, followed by the characters from the
designated set.
5. If the user-preferred character set is not in GR at the end of a block
transmission, the VT300 sends a designating sequence to the host.
This sequence specifies the current user-preferred supplemental set.
The VT300 sends the designating sequence before the end-of-block
character, if any.
Block Transmission in a 7-Bit Environment
National replace character set mode (DECNRCM) is set, or the terminal is in
VT100 mode. The terminal selects the character set for each transmitted char-
acter as follows.
1.
At the beginning of a block transmission, the terminal assumes that
the ASCII set is in GL.
The VT300 sends ASCII graphic and SP characters with their
eighth bit set to 0. The VT300 never sends a designating sequence
for ASCII or space characters.
154 LOCAL EDITING
3. For characters not in the ASCII set, the VT300 sends the appropri-
ate GO designating sequence for the character set containing those
characters (Chapter 5). Then the VT300 sends the characters from
that set.
The VT300 always sends the actual designating sequence for the de-
sired NRC set. This removes any ambiguity for applications that
need to know which NRC set (other than ASCII) is currently in GL.
4. If the same character is in more than one character set, the VT300
uses the following priority system.
— ASCII
— DEC Technical
— DEC Special Graphic
After the VT300 selects the appropriate character set, the VT300
sends the designating sequence followed by the characters from the
designated set.
5. If the NRC set is not in GO at the end of a block transmission, the
VT300 sends a designating sequence to the host. This designator
specifies the current NRC set. The VT300 sends the designating se-
quence before the end-of-block character, if any.
PROGRAMMING TIP: You can program your application to be independent
of the following settings.
National replacement character set mode
VT100 or VT300 mode
ISO level 1 announcer (maps Gl into GR, instead of G2)
To do this, make sure your application can accept 8-bit characters and desig-
nating sequences for GO, Gl, or G2. See Chapter 5 for details on designating
character sets.
LOCAL EDITING 155
SUMMARY
Table 9-3 lists the control functions described in this chapter. You can only use
these control functions in edit mode.
Tablt- 9-3 Local Editing Sequences Summary
Name
Mnemonic
Sequence
Edit mode
DECEDM
Set: CSI ? 10 h
Edit mode.
Reset: CSI ? 10 1
Interactive mode.
Edit key
DECEKEM
Set: CSI ? 16 h
execution mode
Immediate. (D|
Reset: CSI ? 16 I
Deferred.
I. me transmit
DECLTM
Set: CSI ? 11 h
mode
Line.
Reset: CSI ? 1 1 1
Page. (D)
Ti ansmit
TTM
Set: CSI 16 b
termination
Scrolling region. (D)
mode
Reset: CSI 16 1
■;.'■. Partial page. .
VT131
DEC131TM
Set: CSI ? 53 h
transmit
VT131.
mode
Reset: CSI ? 53 1
ANSI. ID)
ID) = default.
156 LOCAL EDITING
Table 9-3 Local Editing Sequences Summary (Cout)
Name
Guarded area
transfer mode
Selected area
transfer mode
Multiple area
transfer mode
Mnemonic
GATM
SATM
MATM
Sequence
Set: CSI I h
All characters. ID)
Reset: CSI 1 I
Unprotected characters.
Set: CSI 17 b
All characters. ID)
Reset: CSI 17 1
Selected characters.
Set: CSI 15 h
All characters. (D)
Reset: CSI 15 1
Area with cursor.
Start selected
■ SSA
8-bit: SSA
area
7-bit: ESC F
find selected
ESA
8-bit: KSA
area ' ■
7-bit: ESC G
Set transmit
DECTTC
Normal
termination
CSI Ps |
character
Ps = end-of-block character.
= no character. (D)
1 = FF (form feed).
2 = ETX (end of text).
3 = EOT (end of transmission)
4 - CR (carriage retui a).
5 = DC3 (XOFFI.
Extended
CSI ? Pn I;...; Pn6 |
Pnl:...:Pn6 = decimal code of end-of-block
character(s).
ID) = default.
LOCAL EDITING 157
Table 9-3
Local Editing Sequences Summary (Cont)
Name
Mnemonic
Sequence
Transmit lir.p
DECTLTC
CSI?Pnl;...;Pn6's
termination
characters
Pnl:...;Pn6 = decimal code of
end-of-line characterise
Default = carriage return (CR)
Space
DECSCFDM
Set: CSI ? 13 h
compression
mode
No spaces.
Reset: CSI ? 13 1
Spaces. (D)
Transmit .
DECTEM
Set: CSI? 14 h
execution
mode
Immediate. (I))
Reset: CSI? 141
Deferred.
Set transmit
STS
ESCS
state
From VT300.
Transmit
DECXMIT
ESCS
From host. .:';■/■"■
ID) = default.
158 LOCAL EDITING
CURSOR MOVEMENT AND PANNING
10
The Cursor, 161
Text Cursor Enable Mode (DECTCEM), 161
Moving the Cursor on the Current Page, 161
Cursor Position (CUP), 162
Horizontal and Vertical Position (HVP), 162
Cursor Forward (CUF), 162
Cursor Backward (CUB), 162
Cursor Up (CUP), 162
Cursor Down (CUD), 163
Panning, 163
Pan Down (SU), 163
Pan Up (SD), 163
Pan Right (SL), 164
Pan Left (SR), 164
Cursor Coupling, 164
Horizontal Cursor Coupling Mode (DECHCCM), 165
Vertical Cursor Coupling Mode (DECVCCM), 165
Page Cursor Coupling Mode (DECPCCM), 166
Summary, 167
This chapter describes the control functions you use to move the cursor and
view different areas in the terminal's page memory. Chapter 6 describes page
memory.
159
Before you read this chapter, you should understand the difference between
scrolling and panning.
Scrolling is the movement of data between the margins of a page. Data
scrolled beyond the margins is lost from page memory. Data is not lost
from the host system's memory.
Panning is the movement of the user window in page memory to view
different parts of a page. You do not lose data in page memory, because
the window moves rather than the data. You only use panning functions
when the page you are viewing is larger than the user window.
For example, suppose the current page is 72 lines x 80 columns. You can
only display 24 lines of the page on the screen. To view other parts of the
page, you can pan the user window up or down.
Figure 10-1 shows the difference between scrolling and panning.
SCROLLING
BBBBBBBBBBB
BBBBBBBBBBB
BBBBBBBBBBB
BBBBBBBBBBB
BBBBBBBBBBB
BBBBBBBBBBB
BBBBBBBBBBB
/
AAAAAAAAAA
AAAAAAAAAA
AAAAAAAAAA
AAAAAAAAAA
A A A AAA A A A A
AAAAAAAAAA
AAAAAAAAAA
BBBBBBBBBBB
BBBBBBBBBBB
BBBBBBBBB
BBBBBBBBB
AFTER SCROLLING UP
AAAAAAAAAA
AAAAAAAAAA
BBBBBBBBBBB
BBBBBBBBBBB
BBB8BBBBBBB
BBBBBBBBBBB
BBBBBBBBBBB
ccccccccccc
ccccccccccc
ccccccccccc
DDDDDDDDDD
DDDDDDDDDD
DATA SCROLLED PAST
TOP MARGIN IS
LOST FROM PAGE
MEMORY
DATA
' ADDED
PAGE
PANNING
USER
WINDOW
A A A A
A A A A
A A A A
AAA A
A A A A
A A A A
A A A A
B B B B E
V A A A A A
\ A A A A A
\ A A A A A
IAAAAA
UAAAA
\ A A A A A
\ A A A A A
BBBBBBBBBBB
BBBBBBBBBBB
B BBBE
BBBBE
BBBBE
AFTER PANNING DOWN
A A AAA A A
A A A A A A A
AAA AAA A
A AAA A A A
A A A A A A A
A A AAA A A
A AAA A A A
B B B B B B B
BB BB BB B
B BBB B B B
B B B B 8B B
BBBBBBBBBB
BBBBBBBBBB
DATA IS NOT
LOST FROM
PAGE MEMORY,
BECAUSE DATA
DOES NOT
MOVE ON PAGE.
- PAGE MUST BE LARGER THAN 24 LINES
Figure 10-1 The Difference Between Scrolling and Panning
160 CURSOR MOVEMENT AND PANNING
A user window is the display area that lets you view data in page memory. The
default user window for the VT300 is the complete screen (24 lines x 80 or
132 columns). You can also divide the screen into two user windows, to view
data from two sessions at the same time. Chapter 8 of Installing and Using
the VT330/VT340 Video Terminal describes how to use windows. Also see
Chapter 14 of this manual for more details on dual sessions.
This chapter covers the control functions you use to move the cursor on a page
and pan the user window across a page or pages.
THE CURSOR
The cursor is a marker that indicates the active position in page memory. The
active position is the point on the current page where the next character is
written.
The default text cursor style is a blinking box. The cursor can also be a steady
box, a blinking underscore, or a steady underscore. The user can select one of
these cursor styles in the Display Set-Up screen. See Chapter 5 of Installing
and Using the VT330/VT340 Video Terminal for details.
Usually, the cursor appears on the screen. However, you can use control func-
tions to move the cursor anywhere on the current page, or to any other page in
page memory.
Text Cursor Enable Mode (DECTCEM)
This control function makes the cursor visible or invisible.
Default: Visible
Action
Makes the cursor visible
if the active position is on
the screen.
Makes the cursor invisible.
MOVING THE CURSOR ON THE CURRENT PAGE
This section describes the control functions you can use to move the cursor on
the current page. Remember, page and display are two different concepts. The
area of the main display is restricted to the screen — 24 lines by 80 or 132
columns. The area of the current page can be 24, 36, 72 or 144 lines by 80 or
132 columns, depending on the page format you select (Chapter 6).
CURSOR MOVEMENT AND PANNING 161
Mode
Sequence
Set
(Visible)
CSI ?
9/11 3/15
2
3/2
5
3/5
h
6/8
Reset
(Invisible)
CSI ?
9/11 3/15
2
3/2
5
3/5
1
6/12
NOTE: Some CO and Cl control characters not covered in this chapter also
move the cursor. See Chapter 2 for detailed descriptions of these control
characters.
In the following sequences, the parameters Pn, PI, and Pc indicate cursor posi-
tion. If you omit a parameter or use a value of 0, the terminal uses a default
value of 1.
Name
Sequence
Action
Cursor
position
(CUP)
CSI PI ; Pc H
9/11 3/? 3/11 3/? 4/8
Horizontal
and vertical
position (HVP)
CSI PI ; Pc f
9/11 3/? 3/11 3/? 6/6
Cursor
CSI
Pn
C
forward
9/11
3/?
4/3
(CUF)
Cursor
CSI
Pn
D
backward
9/11
3/?
4/4
(CUB)
Cursor up
CSI
Pn
A
(CUU)
9/11
3/?
4/1
Moves the cursor to line
PI, column Pc. The
starting point for lines
and columns depends on the
setting of origin mode
(DECOM). CUP applies only
to the current page.
If PI is or 1, the
cursor moves to the first
line of the page. If Pc is
or 1, the cursor moves
to the first column of the
page.
Works the same as CUP.
New applications should
use CUP instead of HVP.
HVP is provided for
compatibility with earlier
Digital products.
Moves the cursor right Pn
columns. The cursor stops
at the right border of the
page border.
Moves the cursor left Pn
columns. The cursor stops
at the left border of the
page.
Moves the cursor up Pn
lines in the same column.
The cursor stops at the
162 CURSOR MOVEMENT AND PANNING
Cursor down
(CUD)
CSI
9/11
Pn B
3/? 4/2
top margin. If the
cursor is already above
the top margin, the cursor
stops at the top line.
Moves the cursor down Pn
lines in the same column.
The cursor stops at the
bottom margin. If the
cursor is already below
the bottom margin, the
cursor stops at the bottom
line.
PANNING
You can display any part of the current page by moving the user window
across the page. The following control functions let you pan the user window up
or down, left or right. To a user viewing the screen, data appears to scroll in
the opposite direction. For example, if you pan up, the data appears to scroll
down.
In the following sequences, Pn indicates the cursor position. If you omit Pn or
use a value of 0, the terminal uses a default value of 1. The term current page
refers to the page with the cursor.
NOTE: The ANSI mnemonics in parentheses are provided only for reference.
These mnemonics do not indicate how the VT300 uses the panning functions.
For example, the ANSI mnemonic for pan down is SU (scroll up).
Name
Pan down
(SU)
Sequence
CSI Pn S
9/11 3/? 5/3
Pan up
(SD)
CSI Pn T
9/11 3/? 5/4
Action
Moves the user window
down Pn lines in page
memory. Pn new lines
appear at the bottom of
the display. Pn old lines
disappear at the top of
the display. You cannot
pan past the bottom margin
of the current page.
Moves the user window
up Pn lines in page
CURSOR MOVEMENT AND PANNING 163
memory. Pn new lines
appear at the top of
the display. Pn old lines
disappear at the bottom of
the display. You cannot
pan past the top
margin of the current
page.
Pan right CSI Pn sp @ Moves the user window
(SL) 9/11 3/? 2/0 4/0 right Pn columns in page
memory. Pn new columns
appear at the right of the
display. Pn old columns
disappear at the left of
the display. You cannot
pan past the right page
border.
Pan left CSI Pn sp A Moves the user window
(SR) 9/11 3/? 2/0 4/1 left Pn columns in page
memory. Pn new columns
appear at the left of the
display. Pn old columns
disappear at the right of
the display. You cannot
pan past the left page
border.
CURSOR COUPLING
This section describes control functions that make the user window pan with
the cursor when the cursor moves past the window boundaries. These functions
are called cursor coupling modes.
A coupled cursor is a cursor that appears to pull the user window through the
page. When an application tries to write data beyond the borders of the user
window, it pans in that direction to keep the cursor visible in the display. The
cursor looks like it is connected, or coupled, to the display.
You can have applications set the coupling modes to cause automatic panning.
You can also reset the coupling modes to write data into off-screen page
memory.
164 CURSOR MOVEMENT AND PANNING
Horizontal Cursor Coupling Mode (DECHCCM)
This control function determines whether the user window pans with the cursor
when the cursor moves past the left or right border of the window. DECHCCM
is only useful when the width of the current user window is narrower than the
page. The cursor must stay on the current page.
Default: Uncoupled
Mode
Sequence
Action
Set
(Coupled)
CSI ? 6 h
9/11 3/15 3/6 3/0 6/8
Reset
(Uncoupled)
CSI ? 6 1
9/11 3/15 3/6 3/0 6/12
Couples the cursor to the
display for horizontal
movement. When the cursor
tries to move past the
left or right border of
the user window, the
window pans to keep the
cursor in view.
If the cursor tries to
move past the left border
of the user window, the
window pans left. New
columns appear at the
left, while columns at the
right move out of view.
Uncouples the cursor from
the display, for
horizontal movement. If
the cursor moves past the
left or right border of
the user window, the
cursor disappears.
Vertical Cursor Coupling Mode (DECVCCM)
This control function determines whether the user window pans with the cursor
when the cursor moves past the top or bottom border of the user window.
DECVCCM is only useful when the height of the current user window is
smaller than the page. The cursor must stay on the current page.
CURSOR MOVEMENT AND PANNING 165
Default: Coupled
Mode Sequence
Set
(Coupled)
CSI ? 6 1 h
9/11 3/15 3/6 3/1 6/8
Reset
(Uncoupled)
CSI ? 6 11
9/11 3/15 3/6 3/1 6/12
Action
Couples the cursor to the
display for vertical
movement. If the cursor
tries to move past the top
or bottom border of the
user window, the window
pans to keep the cursor in
view.
If the cursor tries to
move past the top of the
display, the user window
pans up. New lines appear
at the top of the screen,
while lines at the bottom
move out of view.
Uncouples the cursor from
the display. If the
cursor moves past the top
or bottom border of the
user window, the cursor
disappears.
Page Cursor Coupling Mode (DECPCCM)
This control function determines if a new page appears in the display when the
cursor moves to a new page. DECPCCM is only useful with a multiple-page
format (Chapter 6).
Action
Couples the cursor to the
display when the cursor
moves to a new page. The
new page appears in the
display to keep the cursor
visible.
Default: Coupled
Mode
Sequence
Set
CSI ? 6 4 h
(Coupled)
9/11 3/15 3/6 3/4 6/8
166 CURSOR MOVEMENT AND PANNING
Reset CSI ? 6 4 1
(Uncoupled! 9/11 3/15 3/6 3/4 6/12
Uncouples the cursor from
the display. If the cursor
moves to a new page, the
cursor disappears.
SUMMARY
Table 10-1 lists the control functions described in this chapter.
Table 10-1 Cursor Movement and Panning Sequences
Name Mnemonic
Enabling the Cursor
Text cursor DECTCEM
enable mode
Sequence
Set: CSI ? 25 h
Visible cursor. (D)
Reset: CSI ? 25 1
Invisible cursor.
Moving the Cursor*
Cursor
position
Horizontal
and vertical
position
Cursor
forward
Cursor
backward
Cursor up
Cursor down
CUP
HVP
CUF
CUB
CUT)
CUD
CSI PI : P( H
Line PI, column Pc.
CSI PI ; Pc f
Line PI. column Pc.
(Recommend use of CUP.
CSI Pn C
Pn columns right.
CSI Pn D
Pn columns left.
CSI Pn A
Pn lines up.
CSI Pn B
Pn lines down.
(D) = default.
* In these sequences, the default value for Pn. PI. and Pc is 1.
CURSOR MOVEMENT AND PANNING 167
Table 10-1 Cursor Movement
and Punning Si-quenc
Name : :
Mnemonic
Sequence
Panning*
Pan down
SU
CSI Pn S
Pn lines down.
Pan. up
SD
CSI Pn T
Pn lines up.
Pan right
SL
CSI Pn sp @
Pn columns right
Pan left
SR
CSI Pn sp A
Pn columns left.
Horizontal
DECHCCM
Set: CSI ? 60 h
cursor
Coupled
coupling mode
Reset: CSI ? 60 1
Uncoupled (D)
Vertical
DECVCCM
Set: CSI ? 61 h
cursor
Coupled IDI
coupling mode
Reset: CSI ? 61 1
Uncoupled
Pago cursor
DECPCCM
Set: CSI ? 04 h
coupling mode
Coupled (D>
Reset: CSI ? 64 1
Uncoupled
<D) = default.
* In these sequences, the default value for Pn is 1.
168 CURSOR MOVEMENT AND PANNING
KEYBOARD, PRINTING,
AND DISPLAY COMMANDS
11
Keyboard Control Functions, 170
Keyboard Action Mode (KAM), 170
Backarrow Key Mode (DECBKM), 170
Line Feed/New Line Mode (LNM), 171
Autorepeat Mode (DECARM), 172
Autowrap Mode (DECAWM), 172
Cursor Keys Mode (DECCKM), 173
Numeric Keypad, 173
Keypad Numeric and Application Modes (DECKPAM and DECKPNM),
173
Numeric Keypad Mode (DECNKM). 174
Typewriter or Data Processing Keys, 174
Keyboard Usage Mode (DECKBUM), 175
User-Defined Keys (DECUDK), 175
Using UDKs, 176
UDK Memory Space, 176
Programming UDKs, 176
Printer Port Control Functions, 181
Printer Extent Mode (DECPEX), 181
Print Form Feed Mode (DECPFF), 181
Printing Functions, 182
Printing a Display Line: Autoprint Mode, 183
Sending Characters Directly to the Printer: Printer
Controller Mode, 183
Print Page, 183
Print Composed Main Display, 184
Print All Pages, 184
Print Cursor Line, 184
169
Start Printer-to-Host Session, 184
Stop Printer-to-Host Session, 184
Assign Printer to Active Host Session, 185
Release Printer, 185
Printing Visual Attributes, 185
Sending Line Attributes, 185
Sending Visual Character Attributes, 186
Screen Display Control Functions, 186
Local Echo: Send/Receive Mode (SRM), 186
Light or Dark Screen: Screen Mode (DECSCNM), 187
Scrolling Mode (DECSCLM), 187
Selecting the Indicator or Host Status Line, 188
Select Active Status Display (DECSASD), 189
Select Status Display Type (DECSSDT), 189
Summary, 190
KEYBOARD CONTROL FUNCTIONS
This section describes control functions that affect keyboard operation.
Keyboard Action Mode (KAM)
This control function locks or unlocks the keyboard.
Default: Unlocked
Mode Sequence Action
Set CSI 2 h Locks the keyboard. The
(Locked) 9/11 3/2 6/8 keyboard cannot send characters
to the host. The Wait indicator
comes on. The terminal ignores
all keystrokes that send
characters to the host. KAM
does not affect the Set-Up
or Switch Session keys.
Reset
CSI 2
1
Unlocks the keyboard. The
(Unlocked)
9/11 3/2
6/12
keyboard can send characters to
the host.
Backarrow Key Mode (DECBKM)
This control function determines whether the <x] key works as a backspace
key or delete key.
170 KEYBOARD, PRINTING, AND DISPLAY COMMANDS
NOTE: For compatibility with Digital's software, you should keep DECBKM
reset (DEL).
Default: Delete key
Mode Sequence
Set
(BS)
Reset
(DEL)
CSI ? 6 7 h
9/11 3/15 3/6 3/7 6/8
CSI ? 6 7 1
9/11 3/15 3/6 3/7 6/12
Action
The < x] key works as a
backspace key. When you
press <x], the terminal
sends a BS character to
the host.
The < x] key works as a
delete key. When you
press <x], the terminal
sends a DEL character to
the host.
Notes on DECBKM
• In edit mode, DECBKM is always reset (DEL).
Line Feed/New Line Mode (LNM)
This control function selects the characters sent to the host when you press
the Return key. LNM also controls how the terminal interprets line feed (LF),
form feed (FF), and vertical tab (VT) characters.
NOTE: For compatibility with Digitals software, you should keep LNM reset
(line feed).
Default: Line feed
Mode
Set
(New line)
Sequence
CSI 2 h
9/11 3/2 3/0 6/8
Action
When the terminal receives
an LF, FF, or VT
character, the cursor
moves to the first column
of the next line.
When you press Return, the
terminal sends both a
carriage return (CR) and
line feed (LF).
KEYBOARD, PRINTING, AND DISPLAY COMMANDS 171
Reset
(Line feed)
CSI 2 1
9/11 3/2 3/0 6/12
When the terminal receives
an LF, FF, or VT
character, the cursor
moves to the current
column of the next line.
When you press Return, the
terminal sends a CR only.
Notes on LNM
• When the auxiliary keypad is in keypad numeric mode (DECKPNM),
the Enter key sends the same character(s) as the Return key.
Autorepeat Mode (DECARM)
This control function determines whether or not keys automatically repeat their
character when held down. If DECARM is set, most keys you press for more
than 0.5 seconds send a character repeatedly until you release the key.
Default: Repeat
Mode Sequence
Action
Set
CSI
? 8
h
(Repeat)
9/11
3/15 3/8
6/8
Reset
CSI
? 8
1
(No repeat)
9/11
3/15 3/8
6/8
Keys autorepeat when
pressed for more than
0.5 seconds.
Keys do not autorepeat.
Notes on DECARM
• The following keys never repeat: Hold Session, Local Print, Switch
Session, Break, Return, Compose Character, Lock, Shift, and Ctrl.
Autowrap Mode (DECAWM)
This control function determines whether or not received characters automati-
cally wrap to the next line when the cursor reaches the right border of a page
in page memory.
172 KEYBOARD, PRINTING, AND DISPLAY COMMANDS
Default: No autowrap
Mode Sequence
Set
(Autowrap)
CSI ? 7 h
9/11 3/15 3/7 6/8
Action
Selects autowrap. Graphic
characters received when
the cursor is at the right
border of the page appear
at the beginning of the
next line. Any text on the
page scrolls up if the
cursor is at the end
of the scrolling region.
Turns off autowrap.
Graphic characters
received when the cursor
is at the right border
of the page replace
characters already on
the page.
Cursor Keys Mode (DECCKM)
This control function selects the sequences the arrow keys send. You can use
the four arrow keys to move the cursor through the current page or to send
special application commands. See Chapter 3 for the sequences the keys send.
Reset
(No autowrap)
CSI ? 7 1
9/11 3/15 3/7 6/12
Default: Cursor
Mode Sequence
Set
(Application)
Reset
(Cursor)
CSI ? 1 h
9/11 3/15 3/1 6/8
CSI ? 11
9/11 3/15 3/1 6/12
Action
Arrow keys send
application sequences to
the host.
Arrow keys send ANSI
cursor sequences to the
host.
Numeric Keypad
The following control functions are for the numeric keypad. The keypad applica-
tion and numeric modes (DECKPAM and DECKPNM) work the same as nu-
meric keypad mode (DECNKM). See Chapter 3 for the sequences the keys
send.
KEYBOARD, PRINTING, AND DISPLAY COMMANDS 173
Keypad Application and Numeric Modes (DECKPAM and DECKPNM) - These
control functions select whether the numeric keypad sends numeric characters
or application sequences to the host.
Default: Numeric characters
Mode Sequence
Application
(DECKPAM)
Numeric
(DECKPNM)
ESC =
1/11 3/13
ESC >
1/11 3/14
Action
Numeric keypad sends
application sequences.
Numeric keypad sends the
characters shown on the
key (number, comma,
period, or minus sign).
Keys PF1 through PF4 send
application sequences.
Notes on DECKPAM and DECKPNM
• When you turn on or reset the terminal, the terminal automatically
selects numeric keypad mode.
Numeric Keypad Mode (DECNKM) - This control function selects whether the
numeric keypad sends numeric characters or application sequences to the host.
Available in: VT300 mode only
Default: Numeric
Mode
Set
(Application)
Reset
(Numeric)
Sequence
CSI ? 6 6 h
9/11 3/15 3/6 3/6 6/8
CSI ? 6 6 1
9/11 3/15 3/6 3/6 6/12
Action
Numeric keypad sends
application sequences.
Numeric keypad sends the
characters shown on the
key (number, comma,
period, or minus sign).
Keys PF1 through PF4 send
control functions.
Notes on DECNKM
DECNKM is provided mainly for use with the request and report
mode (DECRQM/DECRPM) control functions (Chapter 12).
174 KEYBOARD, PRINTING, AND DISPLAY COMMANDS
Typewriter or Data Processing Keys
You can select whether the main keyboard keys act as data processing keys or
typewriter keys. See Chapter 3 for a description of data processing keys.
Keyboard Usage Mode (DECKBUM)
Default: Typewriter keys
Mode Sequence Action
Set
(Data
processing)
Reset
(Typewriter)
CSI ? 6 8 h
9/11 3/15 3/6 3/8 6/8
CSI ? 6 8 1
9/11 3/15 3/6 3/8 6/12
Selects data processing
keys. The terminal sends
the characters on the
right half of the keycaps.
Selects typewriter keys.
The terminal sends the
characters on the left
half of the keycaps.
Notes on DECKBUM
• DECKBUM changes the characters that the main keyboard keys
send. Make sure you are aware of this change if you use
DECKBUM in an application.
• If you use the North American dialect, DECKBUM should always be
reset (typewriter). For all other languages, you can use either mode.
USER-DEFINED KEYS (DECUDK)
The keyboard has 20 function keys on its top row. You can define the codes of
15 of these top-row keys.
F6 through F14
Do
Help
F17 through F20
The other five keys — Hold Session, Local Print, Set-Up, Switch Session, and
Break — have dedicated local functions and are not definable.
User-defined keys (UDKs) are only available in VT300 mode. UDKs do not
work in VT100 and VT52 modes.
KEYBOARD, PRINTING, AND DISPLAY COMMANDS 175
Using UDKs
There are two ways to enter definitions for the 15 UDKs.
• Type in the definitions by using the UDK Set-Up screen. See
Chapter 7 of Installing and Using the VT330/VT340 Video Terminal.
• Program the definitions with DECUDK device control strings.
This chapter describes how to program the keys using a DECUDK device con-
trol string.
After you define a key, you can use the new function by pressing Shift- < key >,
where < key > is the key you defined.
UDK Memory Space
There are 256 bytes of memory available for the 15 user-defined keys. Space is
supplied on a first-come/first-serve basis. When the 256 bytes are full, you can-
not define any more keys until you clear some of the memory space. There are
five ways you can clear space.
Redefine one or more UDKs by using the UDK Set-Up screen.
Redefine one or more UDKs by using a DECUDK control string.
Clear one or more UDKs by using a DECUDK control string.
Clear one or more UDKs by using the UDK Set-Up screen.
Clear all UDKs with a terminal power-up or reset (RIS) operation.
Programming UDKs
You use the following device control string format to down-line-load definitions
for user-defined keys. See Chapter 2 for general information about device con-
trol strings.
DECUDK Device Control String Format
Available in: VT300 mode only
DCS Pc;Pl | Kyl/Stl;...Kyn/Stn ST
Key Definition String String
Terminator
Device
Clear
Final
Control
and Lock
Character
String
Parameters
Introducer
176 KEYBOARD, PRINTING, AND DISPLAY COMMANDS
where
DCS (9/0)
indicates the beginning of a device control string. DCS is an 8-bit
CI character. You can use ESC P (1/11 5/0) for a 7-bit environment.
Pc
is the clear parameter, Pc selects how to clear key definitions.
Pc Action
(default) Clear all keys before loading new values,
or none
1 Clear one key at a time, before loading a new
value.
When Pc is 1, the terminal only clears the keys you are loading. By
using a Pc value of 1, you can redefine some keys without redefining
them all.
NOTE: There are 256 bytes of memory for all user-defined keys. A
key definition can only use the number of bytes available when that
key is loaded.
PROGRAMMING TIP: If Pc is 1, a key load may fail because no
memory space is available. The reason for this is as follows.
With Pc set to 1, keys are cleared and loaded sequentially. If the
new definition for a key is larger than the old one, you may exceed
the 256 byte limit.
For example, suppose F6 contains 120 bytes, F7 contains 110 bytes,
and F8 contains 20 bytes. You try to load F8 with 40 bytes, F6 with
1 byte, and F7 with 1 byte, in that order. This works if all keys are
cleared first (Pc is 0), but not if keys are cleared one at a time (Pc is
1). When you try to load F8 with 40 bytes, the load fails because
only 26 bytes are free at that time.
256 (maximum) - 120 (in F6) - 110 (in F7) = 26
KEYBOARD, PRINTING, AND DISPLAY COMMANDS 177
PI
is the lock parameter. PI determines whether the key definitions are
locked or unlocked after you load them.
PI Action
or none Lock the keys. If you want to load new
values into the keys, you must unlock the
keys by using set-up.
1 (default) Do not lock the keys. The keys are
unlocked and can be redefined with
another DECUDK string.
NOTE: If PI is 1 and the keys are already locked, nothing happens,
The terminal uses a special lock to allow or prevent the program-
ming of user-defined keys. You can turn on this lock from set-up or
from the host (with a DECUDK device control string). The lock af-
fects all programmable keys. When you use the lock, you should fol-
lowing these guidelines.
• Unlock the keys to define them.
The keys must be unlocked before you can define them. You can
only unlock the keys from set-up. If a key is locked and an appli-
cation tries to redefine the key with a DECUDK sequence, the
terminal ignores the sequence.
• Lock the keys to prevent redefinition.
You can lock the keys from set-up or from the host (by sending
a DECUDK sequence). New key definitions are locked by default.
is the final character. The vertical bar (7/12) identifies this control
string as a DECUDK.
Kyl/Stl;...Kyn/Stn
are the key definition strings. You include these strings between the
final character (|) and the string terminator (ST). Each string con-
sists of a key selector number (Kyn) and a string parameter (Stn),
separated by a slash (/, 2/15). A semicolon (3/11) separates different
strings.
• The key selector number (Kyn) indicates which key you are de-
fining. Here is a list of definable keys and their identifying
values.
178 KEYBOARD, PRINTING, AND DISPLAY COMMANDS
Key Value Key Value
ST
F6
17
Help
28
F7
18
Do
29
F8
19
F17
31
F9
20
F18
32
F10
21
F19
33
F20
34
Fll
23
F12
24
F13
25
F14
26
The string parameters (Stn) are the encoded definition of the
keys. String parameters consist of hex pairs in the following
ranges.
3/0 through 3/9 (0 through 9)
4/1 through 4/6 (A through F)
6/1 through 6/6 (a through f)
When you combine these hex values, they represent an 8 -bit
quantity. The ASCII table in Chapter 2 lists the hex values of
characters.
This method lets you use any of the 256 character codes in the
key string. You can enter key definition strings in any order.
Default: Empty. The key is undefined.
is the string terminator. ST (9/12) is a Cl 8-bit character. You can
use ESC \ (1/11, 5/12) for a 7-bit environment.
Notes On Loading UDKs
Here are some general guidelines you should keep in mind when loading UDKs.
• Clear UDK memory space before loading new definitions-
Use a DECUDK string to clear keys without locking them. Then
you can use another DECUDK string to redefine the keys and lock
them.
• If you redefine a key, the old definition is lost.
KEYBOARD, PRINTING, AND DISPLAY COMMANDS 179
This may clear some space if the new definition uses less bytes than
the old one.
• There are two ways to lock UDKs, but only one way to unlock them.
To lock UDKs, you can use the UDK Set-Up screen or a DECUDK
control string. To unlock UDKs, you must use the UDK Set-Up
screen.
• The default value for each key definition is empty.
When you clear UDKs, they are empty.
• You can save UDK definitions by using the UDK Set-Up screen.
See Chapter 7 of Installing and Using the VT330/VT340 Video
Terminal for details.
• An invalid hex pair in a DECUDK string stops a UDK load
sequence.
When a load sequence stops (due to error or other cause), the termi-
nal saves any keys already loaded and sends the rest of the
DECUDK sequence to the screen.
Examples of DECUDK Device Control Strings
• The following sequence clears UDKs.
DCS ; 1 | ST
• The following sequence locks UDKs.
DCS 1 ; | ST
• Suppose you want to define the F20 key to be "PRINT", without
clearing or locking any other keys. The first part of your sequence
would look like this.
DCS 1 ; 1 | 3 4 /
where 34 is the code for the F20 key.
After the slash character (2/15), you include the definition. The rest
180 KEYBOARD, PRINTING, AND DISPLAY COMMANDS
of the sequence after the slash character would look like this.
5052494E54ST
where the hex encoding for "PRINT" is as follows.
50 = P
52 = R
49 = I
4E = N
54 = T
The ST character (9/12) marks the end of the control
string.
The complete string is as follows.
DCS 1 ; 1 | 34 / 50 52 49 4E 54 ST
PRINTER PORT CONTROL FUNCTIONS
This section describes control functions you use to control a local printer.
Printer Extent Mode (DECPEX)
This control function selects how much data you can print when you use the
print page function described in the next section.
Default: Scrolling region
Mode
Set
(Page)
Reset
(Scrolling
region)
Sequence
CSI ? 19
9/11 3/15 3/1 3/9
CSI ? 19
9/11 3/15 3/1 3/9
h
6/8
1
6/12
Action
The print page function
prints the complete page.
The print page function
only prints the scrolling
region (data inside the
margins).
Print Form Feed Mode (DECPFF)
This control function selects whether or not the terminal sends a form feed
(FF) character to the printer at the end of a printing function.
KEYBOARD, PRINTING, AND DISPLAY COMMANDS 181
Default: No form feed
Mode Sequence
Set CSI ? 1 8 h
(Formfeed) 9/11 3/15 3/1 3/8 6/8
Reset CSI ? 18 1
(No form feed) 9/11 3/15 3/1 3/8 6/12
Action
The terminal sends a form
feed (FF) to the printer
at the end of a printing
function.
The terminal sends nothing
to the printer at the end
of a printing function.
Notes on DECPFF
• DECPFF does not affect the print cursor line function described in
the next section.
PRINTING FUNCTIONS
This section describes control functions you use to print text from the terminal.
If you do not have a printer connected to the terminal, the terminal ignores
these functions.
When you print characters from the screen or current page, the printer con-
verts all tabs to spaces. Printed characters are spaced with the space <SP) char-
acter. The terminal sends a carriage return (CR), line feed (LF), vertical tab
(VT), or form feed (FF) character to the printer after the last printed character
on a line.
All the printing functions described in this section are variations of the media
copy (MC) command. There are two versions of the MC command, standard
and DEC private. The format of each version is as follows.
MC ANSI standard
MC DEC private
CSI
Ps
i
9/11
3/?
6/9
CSI
?
Ps
i
9/11
3/15
3/?
6/9
wher€
i
Ps indicates the function of the command
182 KEYBOARD, PRINTING, AND DISPLAY COMMANDS
Printing a Display Line: Autoprint Mode
In this mode, the printer prints a line from the screen when you move the
cursor off that line with an LF, FF, or VT character, or an autowrap occurs.
The printed line ends with a CR and the character (LF, FF, or VT) that moved
the cursor off the previous line.
Sequence Action
CSI ? 5 i Turns on autoprint mode.
CSI ? 4 i Turns off autoprint mode.
Sending Characters Directly to the Printer:
Printer Controller Mode
In this mode, the terminal sends received characters to the printer without dis-
playing them on the screen. The terminal sends all characters and control se-
quences to the printer, except NUL, XON, XOFF, and the printer controller
mode sequences.
Sequence Action
CSI 5 i Turns on printer controller mode.
CSI 4 i Turns off printer controller mode.
Notes on Printer Controller Mode
• Printer controller mode cancels autoprint mode. When the terminal
leaves printer controller mode, the terminal returns to the normal
method for printing operations.
• The printer's active column position should always be on the left
margin before the terminal leaves printer controller mode.
Print Page
This control function prints the page that has the cursor. The terminal stores
data from the keyboard until printing is complete.
You can use either of the following sequences to print the page.
CSI i or CSI i
Notes on Print Page
• If printer extent mode (DECPEX) is currently reset, the print page
function only prints the scrolling region.
KEYBOARD, PRINTING, AND DISPLAY COMMANDS 183
Print Composed Main Display
This control function prints the data on the screen. This data may include in-
formation from two sessions, if the screen is displaying data from both ses-
sions. See Chapter 14 for information of dual sessions.
CSI ? 10 i
Notes on Print Composed Main Display
• Printer extent mode (DECPEX) does not affect this function.
Print All Pages
This control function prints all pages in page memory for the current session.
For example, if the current page format is 3 pages of 24 lines each, the printer
prints 3 pages of 24 lines. The terminal stores new data from the keyboard
until printing is complete.
CSI ? 11 i
Notes on Print All Pages
• If print form feed mode (DECPFF) is set, the terminal sends a form
feed (FF) to the printer after each page.
Print Cursor Line
This control function prints the line that has the cursor. The cursor does not
move.
CSI ? 1 i
Start Printer-to-Host Session
This control function enables communication from the printer port to the active
host session. See Chapter 14 for details on session management.
CSI ? 9 i
Stop Printer-to-Host Session
This control function disables communication from the printer port to the ac-
tive host session. See Chapter 14 for details on session management.
CSI ? 8 i
184 KEYBOARD, PRINTING, AND DISPLAY COMMANDS
Assign Printer to Active Host Session
This control function lets the terminal accept printer commands from the cur-
rent session only . See Chapter 14 for details on session management.
Software should use a device status report (DSR) to ask if the printer is not
assigned to the other session. If the inactive session sends a DSR while the
printer is assigned to the active session, the inactive session receives a "printer
assigned" message. See Chapter 12 for details on DSR reports.
CSI ? 18 i
Release Printer
This control function lets the terminal accept printer commands from both ses-
sions. See Chapter 14 for details on session management.
CSI ? 19 i
PRINTING VISUAL ATTRIBUTES
This section describes how the terminal sends visual attributes to a local
printer, such as bold or underlining. To send visual attributes, the Printed Data
Type feature in the Printer Set-Up screen must be set to one of the following
three modes.
national and line drawing
multinational
print all characters
See Chapter 11 of Installing and Using the VT330/VT340 Video Terminal for
details.
The VT300 can send two types of visual attributes, line attributes and visual
character attributes.
Sending Line Attributes
The terminal sends line attributes to a printer by (1) sending the appropriate
line attribute control function, followed by (2) the characters in the current line.
There are four line attribute control functions.
Single-width line ESC # 5
Double-width line ESC # 6
Double-width/double-height line
Top half ESC * 3
Bottom half ESC # 4
KEYBOARD, PRINTING, AND DISPLAY COMMANDS 185
Sending Visual Character Attributes
The terminal initializes character attributes at the beginning of each print line
or print page operation by sending the following SGR sequence to the printer
(Chapter 7).
ESC [ m
This sequence sets all character attributes to the normal rendition.
To send a visual character attribute to a printer, the VT300 (1) sends the ap-
propriate SGR sequence for that attribute, followed by (2) the current charac-
ter. The SGR sequence is as follows.
ESC[0;Ps;Ps;...Psin
where
Ps indicates a character attribute sent.
Ps Attribute
Normal (all attributes off)
1 Bold
2 Underline
5 Blink
7 Invisible
NOTE: The terminal sends characters with the invisible attribute as spaces.
After each print line or print page operation, the terminal clears all attributes
by sending the following sequence.
ESC [ m.
SCREEN DISPLAY CONTROL FUNCTIONS
This section describes control functions that affect how the terminal displays
data.
Local Echo: Send/Receive Mode (SRM)
This control function turns local echo on or off. When local echo is on, the
terminal sends keyboard characters to the screen. The host does not have to
send (echo) the characters back to the terminal display. When local echo is off,
the terminal only sends characters to the host. It is up to the host to echo
characters back to the screen.
186 KEYBOARD, PRINTING, AND DISPLAY COMMANDS
Default: No local echo
Mode Sequence
Set
(No local
echo)
Reset
(Local
echo)
CSI 1 2 h
9/11 3/1 3/2 6/8
CSI 1 2 1
9/11 3/1 3/2 6/12
Action
Turns local echo off. The
terminal sends keyboard
characters to the host
only. The host can echo
the characters back to
the screen.
Turns local echo on. The
terminal sends keyboard
characters to the host and
to the screen. The host
does not have to echo
characters back to the
terminal.
Light or Dark Screen: Screen Mode (DECSCNM)
This control function selects a dark or light background on the screen.
Default: Dark background
Mode Sequence Action
Set
(Light
background)
Reset
(Dark
background)
CSI ? 5 h
9/11 3/15 3/5 6/8
CSI ? 5 1
9/11 3/15 3/5 6/12
Selects reverse video.
The screen displays dark
characters on a light
background.
Selects a normal display.
The screen displays light
light characters on a dark
background.
Notes on DECSCNM
• Screen mode only affects how the data appears on the screen.
DECSCNM does not change the data in page memory.
Scrolling Mode (DECSCLM)
This control function selects the way the terminal scrolls lines. You can select
one of two scroll settings, smooth or jump.
KEYBOARD, PRINTING, AND DISPLAY COMMANDS 187
Default: Smooth scroll
Mode Sequence
Set
(Smooth)
CSI ? 4 h
9/11 3/15 3/4 6/8
Display Set-Up. See
Reset
(Jump)
CSI ? 4 1
9/11 3/15 3/4 6/12
Action
Selects smooth scroll at
a rate of 6 lines per
second. You can select a
smooth scroll speed of 3
or 12 lines per second in
Installing and Using the
VT330/VT340 Video
Terminal, Chapter 5.
Selects jump scroll.
The terminal can add lines
to the screen as fast as
it receives them.
Notes on DECSCLM
• If "no scroll" is selected in Display Set-Up, the terminal ignores
DECSCLM.
Selecting the Indicator or Host-Writable Status Line
The twenty-fifth line at the bottom of the screen is reserved for the status line.
The terminal lets you use the status line in two ways — as an indicator of the
terminal's current state, or as a window the host can use to display application-
specific messages.
The indicator status line displays information about the current state of the
terminal. This status line is enabled by default. It appears in reverse video
(negative image) on the twenty-fifth screen line. This status line always appears
in set-up.
The indicator status line displays the following information about the terminal.
• Active session number (1 or 2)
• Page number
• Text cursor position (line, column) or ReGIS graphics input position
(pixel row, pixel column)
• Edit mode setting (in edit mode only)
• Insert/replace mode setting (in set-up and edit mode only)
• Printer status
• Modem status
188 KEYBOARD, PRINTING, AND DISPLAY COMMANDS
The host-writable status line can display specific information from the host.
That is, you can program this status line to display any information you want.
In a dual session environment, each session has its own host-writable status
line. See Chapter 14 for more information on dual sessions.
You can send data to the status line and select the type of status line with the
following control sequences.
Select Active Status Display (DECSASD) - This control function selects
whether the terminal sends data to the main display or the status line. The
main display is the first 24 lines on the screen. The status line is the twenty-
fifth line.
Available in: VT300 mode only
Default: Main display
CSI Ps $ }
9/11 3/? 2/4 7/13
where
Ps represents the display the terminal sends data to, as follows.
Ps Action
(default) Selects the main display. The terminal sends data to
the main display only.
1 Selects the status line. The terminal sends data to the
status line only.
Select Status Line Type (DECSSDT) - This control function lets the host se-
lect the type of status line displayed on line 25 of the screen.
Available in: VT300 mode only
Default: Indicator status line
CSI Ps $
9/11 3/? 2/4 2/13
where
Ps indicates which status line the host selects, as follows.
Ps Status Line Selected
No status line (The 25th line is blank.)
KEYBOARD, PRINTING, AND DISPLAY COMMANDS 189
1 (default)
2
Notes on DECSSDT
Indicator status line
Host-writable status line
If you change from an indicator to a host-writable status line, the
new host-writable status line is empty.
When you select the host-writable status line, most of the control
functions that affect the main display also affect the status line. The
following list describes the exceptions to the above rule.
Control Function
Select character set
(SCS)
Cursor position
controls
Action
Both the main display and status line
use the same character set.
Only the column parameters in cursor
positioning commands operate in the
status line.
ANSI mode (DECANM) Ignored if received in the status line.
Set conformance level Exits status line.
(DECSCL)
Scrolling mode
(DECSCLM)
Soft terminal reset
(DECSTR)
Insert/replace mode
(IRM)
Hard terminal reset
(RIS)
Tab stops
Auto wrap mode
(DECAWM)
Affects the main display and the
status line.
Exits status line.
Affects the main display
and the status line.
Erases and exits the
status line.
Affect main display and status line.
Affects main display and
status line.
• DECSSDT does not affect the status line type displayed in set-up.
In set-up, the terminal always uses the indicator status line.
SUMMARY
Tables 11-1 through 11-4 list the control sequences described in this chapter.
190 KEYBOARD, PRINTING, AND DISPLAY COMMANDS
Table 111 Keyboard Control Sequences
Mode Mnemonic Sequence
Set
Reset
Keyboard
action mode
KAM
CSI 2 h
Locked.
CSI 2 !
Unlocked.lD)
Backarrow key
mode;
DECBKM
CSI ? 67 h
Backspace.
CSI ? 67 1
Delete. ID!
Line feed/
new line mode
LNM
CSI 20 h
New line.
CSI 20 1
Line feed. ID)
Autorepeat
mode
DEC ARM
CSI ? 8 h
Repeat. (Dl
CSI ? 8 1
No repeat.
Autowrap
mode
DECAWM
CSI ? 7 h
Autowrap.
CSI ? 7 1
No autowrap. (D)
Cursor keys
mode
DECCKM
CSI ? 1 h
Application.
CSI ? 1 1
Cursor. (D)
Keypad
application/
numeric modes
DECKPAM
DECKPNM
ESC =
Application.
ESC >
Numeric. (D)
Numeric
keypad mode
DEC N KM
CSI ? 66 h
Application.
CSI ? 66 1
Numeric. (D)
Keyboard
usage mode
DECKBUM
CSI ? 68 h
Data processing.
CSI ? 68 1
Typewriter. (D)
(D) = default.
KEYBOARD, PRINTING, AND DISPLAY COMMANDS 191
Table 11-2 Programming UDKs
Definable Keys
F6 through F14 Help(Fl(5)
Do(F15) Fl 7 through F20 "'. W.-x
DECUDK Device Control String Format
DCS Pc : PI | Kyl/Stl;...Kyn/Stn ST
Pc is the clear parameter. ■ ■'■ ,'/.'•■',■ " ■
or none = Clear all keys before loading new values (default)
1 = Clear one key at a time, before loading a new value.
PI is the lock parameter.
or none = Lock the keys. .'..■■ : . './.'.
1 ~ Do not lock the keys (default).
Ky.l/Stl;...Kyn/Stn am the key definition strings,
The key selector number (Kyu) indicates which key you are defining.
Key Value Key Value Key Value
F6
17
Fll
23
Do
29
F7
18
F12
24
F17
31
F8
19
F13
25
F18
32
F9
20
F14
26
Fl 9
zz
F10
21
Help
28
■/,:'.. F20'
34
The string parameters (St.nl are the key definitions, encoded as pairs of
hex codes.
3/0 through 3/9 (0 through fl)
4/1 through 4/(5 (A through F)
(5/1 through (5/6 (a through f)
192 KEYBOARD, PRINTING, AND DISPLAY COMMANDS
Table 11-3 Printing Control Sequences
Name
Mnemonic
Sequence
Printer extent mode
DECPEX
Set: CSI ? 19 h
Page. (D)
Reset: CSI ? 19 1
Scrolling region.
Print form feed mode
DECPFF
Set: CSI ? 18 h
Form feed.
Reset: CSI ? 18 1
No form feed. (D)
Auto print mode
MC
On: CSI ? 5 i
Off: CSI ? 4 i
Printer controller mode
MC
On: CSI 5 i
Off: CSI 4 i
Print page
MC
CSI i or CSI i
Print composed main
display
MC
CSI ? 10 i
Print all pages
MC
CSI ? 11 i
Print cursor line
MC
CSI ? 1 i
Start printer-to-host
session
MC
CSI ? 9 i
Stop printer-to-host
session
MC
CSI ? 8 i
Assign printer
to active session
MC
CSI ? 18 i
Release printer
MC
CSI ? 19 i
(D) = default.
KEYBOARD, PRINTING, AND DISPLAY COMMANDS 193
Table 11-4 Screen Display Control Sequences
Name Mnemonic
Send/receive mode SRM
Screen mode
Scrolling mode
Select, active
status display*
Select status
line type*
DECSCNM
DKCSCLM
l.)i;:CSASI)
DKCSSDT
(D) = default.
* Available in VT300 mode onlv.
Sequence
Set: CSI 12 h
Local echo off. (Dl
Reset: CSI 12 1
Local echo on.
Set: CSI ? 5 h
I ;ight background.
Reset: CSI ? 5 I
Dark background. (D)
Set: CSI ? 4 h
Smooth scroll. ID)
Reset: CSI ? 4 1
Jump scroll.
csi Ps $ :
p s = o. main display
Ps = 1 . status line.
CSI Ps $ -
Ps = : 0. none. '
Ps = 1, indicator. (D)
Ps = 2. host-writs b <
194 KEYBOARD, PRINTING, AND DISPLAY COMMANDS
VT300 REPORTS
12
Device Attributes (DA), 196
Primary DA, 197
Secondary DA, 199
Terminal Identification (DECID), 200
Device Status Reports (DSR), 201
VT300 Operating Status, 201
Cursor Position Report, 202
Extended Cursor Position Report, 202
Printer Port, 202
User-Defined Keys, 203
Keyboard Dialect, 203
Locator Device Port, 204
Terminal State Reports, 205
Request Terminal State Report (DECRQTSR), 206
Request Color Table Report, 206
Terminal State Report (DECTSR), 207
Color Table Report <DECCTR), 207
Restore Terminal State (DECRSTS), 208
Presentation State Reports, 209
Request Presentation State Report (DECRQPSR), 210
Cursor Information Report (DECCIR), 210
Tab Stop Report (DECTABSRI, 216
Restore Presentation State (DECRSPS), 216
Mode Settings, 218
Request Mode (DECRQM), 218
Report Mode (DECRPM), 221
Restoring Mode Settings, 223
Set Mode (SM), 223
Reset Mode <RM), 224
195
Control Function Settings, 225
Request Selection or Setting (DECRQSS), 226
Report Selection or Setting (DECRPSS), 227
Saving and Restoring the Cursor State, 229
Save Cursor (DECSC), 229
Restore Cursor (DECRC), 229
Window Reports, 230
Request Displayed Extent (DECRQDE), 230
Report Displayed Extent (DECRPDE), 230
User-Preferred Supplemental Set (DECRQUPSS), 231
Summary, 233
The VT300 sends reports in response to requests from the host computer.
These reports provide the host with the following information about the
terminal.
identification (type of terminal)
cursor state
operating status
operating level (VT100 or VT300)
almost all terminal states that software can set
The host can use the reports to adjust the computing environment to match
the terminal.
DEVICE ATTRIBUTES (DA)
The terminal and host computer exchange DA sequences to provide the host
with the following information.
conformance level (1, 2, or 3) and extensions
basic features
identification code
firmware version level
hardware options
Based on this information, the host can
• Use the information it receives to make the best use of the terminal's
features.
• Select the correct application software for the terminal.
• Determine the cause of certain communication errors.
196 VT300 REPORTS
There are two types of DA exchanges between the host and the terminal, pri-
mary DA and secondary DA. The host can request a primary DA or secondary
DA report, depending on the information the host needs.
Primary DA
In this DA exchange, the host asks for the terminal's service class code and
basic attributes.
Host Request
The host uses the following sequence to send this request.
CSI c
or
CSI
c
9/11 6/3
9/11 3/0
6/3
Terminal Response
The terminal responds by sending its service code and basic attributes to the
host. This response depends on the terminal's current operating level (VT100
or VT300).
CSI ? Psc
; Psl
J ...
Psn c
9/11 3/15 3/?
3/11 3/?
3/11 ...
3/? 6/3
where
Psc indicates the terminal's service class code. The value of Psc depends
on the terminal's current operating level, as follows.
Psc Operating Level
61 Level 1 (VT100 family)
63 Level 3 (VT200 or VT300 family)
Psl...Psn indicate which of the following extensions the terminal supports.
Ps Meaning
1 132 columns
2 Printer port
3 ReGIS graphics
4 Sixel graphics
6 Selective erase
7 Soft character set (DRCS)
8 User-defined keys
9 National replacement character sets
VT300 REPORTS 197
Ps Meaning
13 Local editing mode
15 Technical character set
16 Locator device port
18 Windowing capability
19 Dual sessions
Primary DA Example
Here is a typical primary DA exchange.
Exchange
Request
(Host to VT300)
Response
(VT300 to host)
Sequence
CSI c or CSI c
CSI ? 63; 1; 2;
3; 4; 6; 7; 8; 9;
13; 15; 16; 17;
18; 19; c
Meaning
The host asks for the
terminal's service code,
conformance level, and
supported extensions.
The terminal is a service
class 3 device (63 and
supports the following
extensions.
132 columns (1)
printer port (2)
ReGIS graphics (3)
Sixel graphics (4)
selective erase (6)
DRCS (7)
UDKs (8)
NRC sets (9)
local editing mode (13)
technical character
set (15)
Locator device port
(16)
windowing (18)
dual sessions (19)
Table 12-1 lists all the primary DA alias responses that the VT300 can send to
the host. The terminal uses an alias response to identify itself to the host as
some other type of terminal. Each response corresponds to a certain operating
level.
198 VT300 REPORTS
Table 12-1 Alias Primary DA Responses From the VT300*
Terminal Identification Sequence
VT100 DA ESC [ ? 1:2 c
VT101 DA ESC[?l;0c
VT102 DA ESC|?6c
VT125DA ESC [? 12;7;1; 10: 102 c
VT131 DA ESC[?7c
VT220 DA CS1 ? 62; 1; 2: 6; 7: 8: 9 c
VT240 DA CSI ? 62: 1 ; 2; 3; 4: 6; 7; 8; 9 c
VT 100 terminal
VT101 terminal
VT102 terminal
VT1 25 terminal
VT131 terminal
VT220 terminal
VT240 terminal
* To change these alias responses, you must use the General Set-Up screen.
See Chapter 5 of Installing and Using the VT3.30.VT340 Terminal.
Secondary DA
In this DA exchange, the host requests the terminal's identification code,
firmware version level, and hardware options.
Host Request
The host uses the following sequence to send this request.
CSI > c
9/11 3/14 6/3
or CSI > c
9/11 3/14 3/0 6/3
Terminal Response
The terminal uses the following sequence to respond.
CSI > Pp ; Pv ; Pc c
9/11 3/14 3/? 3/11 3/? 3/11 3/? 6/3
where
Pp indicates the identification code for the terminal as follows.
Pp Meaning
18 VT330 terminal
19 VT340 terminal
Pv indicates the firmware version level of the terminal. Firmware is the
software implementation of all the terminal's functions (for example, the
VT300 REPORTS 199
editing functions). For the VT300, all firmware is on the ROM cartridge
installed in the rear of the terminal.
Examples
Pv Version
7 X0.7 (prereleased version 0.7)
10 VI. (released version 1.0)
Pc indicates the ROM cartridge registration number. Pc is set to in the
VT300.
Secondary DA Example
Here is a typical secondary DA exchange.
Exchange
Request
(Host to VT300)
Response
(VT300 to host)
Sequence
CSI > c or
CSI > c
CSI > 18; 14; c
Meaning
The host asks for the
terminal's identification,
firmware version, current
hardware options.
The terminal identifies
itself as a VT330 that
uses version 1.4 firmware.
TERMINAL IDENTIFICATION (DECID)
This control function is similar to a primary device attributes (DA) request
from the host. See the previous "Device Attributes" section.
NOTE: Digital does not recommend using DECID. DECID may not be sup-
ported in Digital terminals. You should use the primary device attributes re-
quest for this purpose. In VT300 mode, the terminal ignores DECID.
Host DECID Request
ESC Z
1/11 5/10
Terminal Response
The terminal uses the same response as for a primary DA request. The termi-
nal uses this response for all operating levels (1, 2, or 3).
200 VT300 REPORTS
DEVICE STATUS REPORT (DSR)
The host computer and terminal exchange DSR sequences to provide the host
with the operating status of the following seven features.
VT300 operating status
Cursor position
Cursor position with page
Printer port
User-defined keys
Keyboard dialect
Locator device port
DSR requests and reports follow one of two formats, ANSI standard or DEC
private. The format for each is as follows.
ANSI standard
CSI Ps n
9/11 3/? 6/14
DEC private
CSI ? Ps n
9/11 3/15 3/? 6/14
where
Ps indicates the type of DSR requested.
There is a different DSR request for each feature. The following sections de-
scribe the possible DSR reports. If the terminal is in printer controller mode
(Chapter 11), the printer receives the DSR request.
DSR — VT300 Operating Status
The host requests the terminal's operating status.
Exchange Sequence Meaning
Request
(HosttoVT300)
Responses
(VT300 to host)
CSI 5 n
CSI n
or
CSI3n
The host requests the terminal's
operating status. The host asks if the
terminal is in good operating condition.
The terminal indicates that it is
in good operating condition.
The terminal indicates that it has a
malfunction.
VT300 REPORTS 201
DSR — Cursor Position Report (CPR)
The host asks the terminal for a cursor position report.
Exchange
Sequence
Meaning
Request
CSI6n
The host asks for a cursor
(HosttoVT300)
position report (CPR).
CPR response
CSI PI; Pc R
The terminal indicates that
(VT300 to host)
the cursor is currently at
line PI, column Pc.
DSR — Extended Cursor Position Report (DECXCPR)
The host asks the terminal for the current cursor position, including the cur-
rent page number.
Exchange
Request
(Host to VT300)
Sequence
CSI ? 6 n
DECXCPR response CSI PI; Pc; Pp R
(VT300 to host)
Meaning
The host asks for an extended
cursor position report
(DECXCPR).
The terminal indicates that
the cursor is currently at
line PI, column Pc, on page
Pp.
DSR — Printer Port
The host asks for the status of the terminal's printer.
NOTE: Host software should check the printer status before entering any print
mode or starting any printing function.
Exchange
Request
(HosttoVT300)
Possible responses
(VT300 to host)
Sequence
CSI ? 15 n
CSI ? 13 n
CSI ? 10 n
Meaning
The host asks for the current
printer status.
No printer. The data terminal
ready (DTR) signal has not
been asserted on the printer
port since the last power-up
or reset.
Printer ready. DTR is
asserted on the printer port.
202 VT300 REPORTS
CSI ? 11 n Printer not ready. DTR is not
currently asserted on the
printer port.
CSI ? 18 n Printer busy. DTR is asserted
on the printer port, but the
other session is using the
printer (Chapter 14).
InVTIOOmode.the
terminal sends the "Printer
not ready" sequence above.
CSI ? 19 n Printer assigned to other
session. DTR is asserted
on the printer port, but
the printer is assigned
to the other session. The
printer is not available to
this session (Chapter 14).
InVTIOOmode, the
terminal sends the "No
printer" sequence above.
DSR — User-Defined Keys (VT300 Mode Only)
The host asks if the user-defined keys (UDKs) are locked or unlocked.
Exchange
Request
(Host to VT300)
Possible responses
(VT300 to host)
Sequence
CSI ? 25 n
CSI ? 20 n
CSI ? 21 n
Meaning
The host asks if UDKs are
locked or unlocked.
UDKs are unlocked.
UDKs are locked.
DSR — Keyboard Dialect
The host asks for the current keyboard dialect and the keyboard's operating
status.
Exchange
Request
(Host to VT300)
Sequence
CSI ? 26 n
Meaning
The host asks for the
keyboard dialect and status.
VT300 REPORTS 203
Response
(VT300 to host)
CSI ? 27; Pla;
Pstn
where
Pla
Dialect
The keyboard dialect is Pla,
and the keyboard status is
Pst.
Pst = Keyboard Status*
= Keyboard ready.
The terminal sends
typed characters to
the current session
(Chapter 14).
3 = No keyboard. The
terminal does not
detect the keyboard.
8 = Keyboard busy. The
other session is
currently using the
keyboard (Chapter
14).
* The terminal only sends Pst in VT300 mode.
DSR — Locator Device Port (VT300 Mode Only)
The host can ask for the status or identification of the locator device. You can
connect devices such as a mouse or graphics tablet to the locator port of a
VT300.
1
=
North American
2
=
British
3
=
Flemish
4
=
Canadian (French)
5
=
Danish
6
=
Finnish
7
=
German
8
=
Dutch
9
=
Italian
10
=
Swiss (French)
11
=
Swiss (German)
12
=
Swedish
13
=
Norwegian
14
=
French/Belgian
15
==
Spanish
16
Portuguese
Exchange
Status request
(Host to VT300)
Possible responses
(VT300 to host)
Sequence
CSI ? 55 n
CSI ? 53 n
CSI ? 50 n
Meaning
The host asks for the status
of the locator device port.
No locator device. The
terminal cannot detect
a locator device.
Locator device ready. The
terminal detects a locator
device.
204 VT300 REPORTS
Identification
request
(Host to VT300)
Possible responses
(VT300 to host)
CSI ? 58 n Locator device busy. The
other session is currently
using the locator device
(Chapter 14).
CSI ? 56 n The host asks what kind of
locator device is connected
to the locator device port.
CSI ? 57 ; n Cannot identify the locator
device. There is no locator
device connected, or the
device connected is not
Digital's optional mouse or
tablet.
Applications that receive
this response should request
the locator status before
reporting a problem to the
user.
CSI ? 57 ; 1 n The terminal identifies the
device as Digital's optional
mouse.
CSI ? 57 ; 2 n The terminal identifies the
device as Digital's optional
tablet.
TERMINAL STATE REPORTS (VT300 MODE ONLY)
The host can request the terminal's current operating state. In response to this
request, the terminal returns a terminal state report. The host can use the in-
formation in the report to save the current terminal state. Later, the host can
restore the terminal to the saved state.
This operation is useful for applications that need to temporarily change the
terminal's operating state. When the application is finished, it can restore the
terminal to the previous operating state.
A terminal state report is a device control string. The report indicates the set-
tings of most of the terminal's features. The terminal sends the report in re-
sponse to a request terminal state report (DECRQTSR) sequence from the
host.
VT300 REPORTS 205
There are two terminal state reports.
Terminal state report (DECTSR)
Color table report (DECCTR)
Request Terminal State Report (DECRQTSR) — Host To VT300
The host sends this control function to request a terminal state report
(DECTSR) or color table report (DECCTR). The terminal responds by sending
a report indicating the settings of many device attributes.
CSI Ps $ u
9/11 3/? 2/4 7/5
where
Ps indicates the type of report the host requests from the terminal.
Ps Report Requested
or none Ignored. No report sent.
1 Terminal state report (DECTSR)
2 Color table report (DECCTR)
Request Color Table Report - When you use DECRQTSR to request a color
table report, you can include an additional parameter, Ps2. Ps2 selects which
color coordinate system the terminal uses to report the color map, HLS (hue/
lightness/saturation) or RGB (red/green/blue). Use the following format to re-
quest a color table report.
CSI
2
; Ps2
$
u
9/11
3/2
3/11 3/?
2/4
7/5
where
Ps2 indicates the color coordinate system the terminal uses
the send the report.
Ps2 Color Coordinate System
or none HLS (default)
1 HLS
2 RGB
206 VT300 REPORTS
Terminal State Report (DECTSR) — VT300 to Host
The terminal sends this sequence in response to a request terminal state report
(DECRQTSR) sequence. DECTSR informs the host of the entire state of the
terminal, except for user defined key definitions and the current soft character
set.
PROGRAMMING TIP: Applications can use the information in the terminal
state report to save the current terminal state. Later, the application can re-
store the terminal to the saved state.
This operation is useful for applications that need to temporarily change the
terminal's operating state. When the application is finished, it can restore the
terminal to the previous operating state. You use the restore terminal state
(DECRSTS) function to restore the terminal state. DECRSTS is described later
in this chapter.
The DECTSR format is as follows.
DCS 1 $ s D1...D196 <checksuml> <checksum2> ST
9/0 3/1 2/4 7/3 9/12
where
D1...D196 is a data string indicating the status of most of the terminal's
features. There are 196 bytes in the data string (D1...D196). D1...D196 are
in the range 4/0 to 4/15 in the code table (Chapter 2). Bit 6 of each Dn is
always on, bits 4, 5, and 7 of Dn are always off.
Notes on DECTSR
• Software should not expect the format of DECTSR to be the same for
all members of the VT300 family, or for different revisions within each
member of the family.
Color Table Report (DECCTR) — VT300 to Host
The terminal sends this sequence in response to a request terminal state report
(DECRQTSR) sequence from the host. DECCTR informs the host of the termi-
nal's current color settings.
PROGRAMMING TIP: Applications can use the information in the color table
report to save the current color map. Later, the application can restore the
saved color map.
VT300 REPORTS 207
This operation is useful for applications that need to temporarily change the
terminal's color map. When the application is finished, it can restore the color
map that was in effect before the application changed it. You use the restore
terminal state (DECRSTS) function to restore the color map. DECRSTS is de-
scribed in the next section.
DCS 2
$
s
D...D
ST
9/0 3/2
2/4
7/3
9/12
where
D...D is the data string containing the color table information. The data
string is divided into groups of five
values, as follows.
Pc; Pu; Px; Py; Pz / Pc; Pu; Px; Py; Pz / ...
where
Pc is the color number (0 through 255).
; (semicolon, 3/11) separates the parameters.
Pu indicates the universal coordinate system used.
Pu Coordinate System
1 HLS (hue, lightness, saturation)
2 RGB (red, green, blue)
Px; Py; Pz are color coordinates in the specified coordinate system.
Parameter HLS Values RGB Values
Px to 360 (hue angle) to 100 (red intensity)
Py to 100 (lightness) to 100 (green intensity)
Pz to 100 (saturation) to 100 (blue intensity)
Restore Terminal State (DECRSTS) — VT300 Mode Only
This sequence restores the terminal to a previous state specified in a terminal
state report (DECTSR). There are two terminal state reports.
Terminal state report (DECTSR)
Color table report (DECCTR)
208 VT300 REPORTS
PROGRAMMING TIP: Applications can use DECRSTS to restore the terminal
to a previous operating state specified in a terminal state report. See the
"Terminal State Report (DECTSR)" and "Color Table Report (DECCTR)" sec-
tions in this chapter.
ilable in: VT300 mode
DCS Ps $ p
D...D
ST
9/0 3/? 2/4 7/0
9/12
where
Ps indicates the format of the data string (D...D). You can use one of the
two following formats for the the data string. These formats correspond to
the formats used by the two terminal state reports (DECTSR). Make sure
you use the format used by the report you are restoring.
Ps Data String Format
Error, restore ignored.
1 Selects the format of the terminal state report (DECTSR).
2 Selects the format of the color table report (DECCTR).
D...D is a data string that contains the restored information. This string is
identical to the data string used by the report you are restoring.
Notes on DECRSTS
• If there is an invalid value in the DECRSTS sequence, the terminal
ignores the rest of the sequence. This action may leave the terminal
in a partially restored state.
• Software should not expect the format of the terminal state report
(DECTSR) to be the same for all VT300 family members.
PRESENTATION STATE REPORTS (VT300 MODE ONLY)
The terminal can send two presentation state reports.
Cursor information Reports on the cursor position, including
report (DECCIR) its visual attributes and character
protection attributes. Also reports on
origin mode (DECOM), and the current
active character sets.
Tab stop report Reports the current tab stop settings.
(DECTABSR)
VT300 REPORTS 209
The host can request the terminal's current presentation state. In response to
this request, the terminal returns a presentation state report. The host can use
the information in the report to save the current presentation state. Later, the
host can restore the terminal to the saved state.
This operation is useful for applications that need to temporarily change the
terminal's presentation state. When the application is finished, it can restore
the terminal to the previous presentation state.
A presentation state report is a device control string. The terminal sends the
report in response to a request presentation state report (DECRQPSR) se-
quence from the host.
Request Presentation State Report (DECRQPSR)
— Host To VT300
The host sends this sequence to request a cursor information report (DECCIR)
or a tabulation stop report (DECTABSR>.
CSI Ps $ w
9/11 3/? 2/4 7/7
where
Ps indicates which report the host requests.
Ps Report Requested
Error, request ignored
1 Cursor information report (DECCIR)
2 Tab stop report (DECTABSR)
Cursor Information Report (DECCIR) — VT300 to Host
The terminal sends this sequence in response to a request presentation state
report (DECRQPSR) sequence. DECCIR reports the status of the cursor posi-
tion, including visual attributes and character protection attributes. DECCIR
also reports the status of of origin mode (DECOM) and the current active char-
acter sets.
PROGRAMMING TIP: Applications can use the information in the cursor in-
formation report to save the current presentation state. Later, the application
can restore the terminal to the saved state.
210 VT300 REPORTS
This operation is useful for applications that need to temporarily change the
terminal's presentation state. When the application is finished, it can restore
the terminal to the previous presentation state. You use the restore presenta-
tion state (DECRSPS) function to restore the presentation state. DECRSPS is
described later in this chapter.
DCS 1
$
u
D...D
ST
9/0 3/1
2/4
7/5
9/12
where
D...D is the data string containing the cursor information. The format for
this data string is as follows.
Pr; Pc; Pp; Srend; Satt; Sflag; Pgl; Pgr; Scss; Sdesig
where
Pr is the number of the line the cursor is on.
Pc is number of the column the cursor is at.
Pp is the number of the current page.
Srend is one or more characters indicating the visual attributes
(such as bold and blinking) currently set for writing (Chapter 7).
To find out what attributes are set, you must convert the character
to an 8-bit binary number. You can use the code table in Chapter 2
to convert characters. After you convert a character, you can find
the meaning of its 8-digit binary number in the following table. The
table lists the most significant bit (8) to least significant bit (1).
Bit
8
7
Attribute
Bit Value
Always (off).
Always 1 (on).
6
Extension
indicator
Invisible
1 = another character (byte) of
attribute data follows this
one.
no more attribute data.
= off.
1 = on.
VT300 REPORTS 211
4
Negative
= off.
image
1 = on.
3
Blinking
= off.
1 = on.
2
Underline
= off.
1 = on.
1
Bold
= off.
1 = on.
Example
If the bold and underline attributes are on for the current writ-
ing rendition, Srend is the ASCII uppercase C character (bi-
nary 01000011).
Satt is one or more characters indicating whether the selective erase
attribute (DECSCA, Chapter 8) is currently on for writing.
To find if the attribute is set, you must convert each character to an
8-bit binary number. Use the same method you used to convert the
Srend parameter above. Then use the following table to find the
meaning of the 8-bit binary number.
Bit
Attribute
Bit Value
8
—
Always (off).
7
—
Always 1 (on).
6
Extension
indicator
1 = another character (byte) of
selective erase data
follows this one.
= no more protection data.
5
—
— Reserved for future use.
4
—
— Reserved for future use.
3
—
— Reserved for future use.
2
—
— Reserved for future use.
1
Selective
erase
= off.
1 = on.
212 VT300 REPORTS
Example
If the selective erase attribute is currently on for writing, then
Satt is the ASCII uppercase A character (binary 01000001).
Sflag is one or more characters that indicate several flags and
modes the terminal must save.
To see the current state of the flags and modes, you must convert
each character to an 8-bit binary number. Use the same method you
used to convert the Srend and Satt parameters above. Then use the
following table to find the meaning of the 8-bit binary number.
Bit
8
7
Attribute
Bit Value
Always (off).
Always 1 (on).
6
5
4
Extension
indicator
Auto
wrap
Single
shift 3 (SS3)
setting
Single
shift 2 (SS2)
setting
Origin
mode
1 = another character (byte) of
flag data follows this one.
= no more flag data.
— Reserved for future use.
1 = auto wrap pending
= auto wrap not pending
1 = G3 is mapped into GL for
the next typed character
only.
= single shift 3 is off.
1 = G2 is mapped into GL for
the next typed character
only.
= single shift 2 is off.
1 = origin mode set
= origin mode reset
Example
If origin mode is set, auto wrap is pending, and a single shift
3 has been received, then Sflag is the ASCII upper case M
character (binary 01001101).
VT300 REPORTS 213
Pgl indicates the number of the logical character set (GO through
G3) mapped into GL.
= GO is in GL.
1 = Gl is in GL.
2 = G2 is in GL.
3 = G3 is in GL.
Pgr indicates the number of the logical character set (GO through
G3) mapped into GR.
= GO is in GR.
1 = Gl is in GR.
2 = G2 is in GR.
3 = G3 is in GR.
Scss is a character indicating the size of the character sets in GO
through G3.
To find out what the character means, you must convert it to an
8-bit binary number. Use the same method you used to convert the
Srend, Satt, and Sflag parameters. Then use the following table to
find the meaning of the 8-bit binary number.
Bit
Indicates
Bit Value
8
—
Always (off)
7
—
Always 1 (on)
6
Extension
indicator
1 = another character (byte) of
character size data follows
this one.
= no more size data.
5
—
= reserved for future use.
4
G3 set
size
= 94 characters.
1 = 96 characters.
3
G2set
size
= 94 characters.
1 = 96 characters.
2
Glset
size
= 94 characters.
1 = 96 characters.
1
GO set
size
= 94 characters.
1 = 96 characters.
214 VT300 REPORTS
Example
Suppose the following conditions exist.
• ISO Latin-1 supplemental is designated as G2 and G3.
• ASCII is designated as GO and Gl.
Then Scss is the backslash ASCII \ character (binary
01001100).
Sdesig is a string of intermediate and final characters indicating the
character sets designated as GO through G3. These final characters
are the same as those used in select character set (SCS) sequences
(Chapter 5).
Example
Suppose the ASCII character set is designated as GO, DEC Special
Graphic as Gl, and DEC Supplemental Graphic as G2 and G3. The
Sdesig string would be B0%5%5. Each character corresponds to a
final character in an SCS sequence, as follows.
GO
Gl
G2
G3
B
%5
%5
ASCII
DEC
Special
Graphic
DEC
Supplemental
Graphic
DEC
Supplemental
Graphic
Example
The following is an example of a cursor information report.
DCS 1 $ u 1; 1; 1; @; @; @; 0; 2; @; BB%5%5 ST
where
1; 1; 1; indicates that the cursor is at row 1, column 1, on the first page.
@; @; @; indicates that no visual character attributes or protection attri-
butes are on at the cursor position, DECOM is reset, no SS2 pending, no
SS3 pending, and no autowrap pending.
0; 2; indicates that GO is mapped into GL, and G2 is in GR.
@; all character sets have 94 characters.
BB%5%5 indicates that ASCII is in GO and Gl, and that DEC
Supplemental Graphic is in G2 and G3
VT300 REPORTS 215
Notes on DECCIR
• The cursor information in a DECCIR sequence is the same informa-
tion saved through a save cursor (DECSC) command.
• DECCIR does not save active SPA and SSA control functions.
Tab Stop Report (DECTABSR) — VT300 To Host
The terminal sends this sequence to the host in response to a request presenta-
tion state report (DECRQPSR) sequence. DECTABSR informs the host of the
terminal's current tab settings.
PROGRAMMING TIP: Applications can use the information in the tab stop
report to save the current tab stops. Later, the application can restore the
saved tab stops.
This operation is useful for applications that need to temporarily change the
terminal's tab stops. When the application is finished, it can restore the tab
stops that were in effect before the application changed them. You use the re-
store presentation state (DECRSPS) function to restore tab stops. DECRSPS is
described later in this chapter.
DCS 2
$
u
D...D
ST
9/0 3/2
2/4
7/5
. . .
9/12
where
D...D is a data string indicating the column number location of each tab
stop.
Example
The following is an example of a DECTABSR sequence.
DCS 2 $ u 9/ 17/ 25/ 33/ 41/ 49/ 57/ 65/ 73 ST
where
9, 17, 25, 33, 41, 49, 57, 65, and 73 are the column numbers for tab stops.
Restore Presentation State (DECRSPS) — VT300 Mode Only
This control function restores the terminal to a previous state based on one of
the presentation state reports. There are two presentation state reports.
Cursor information report (DECCIR)
Tab stop report (DECTABSR)
216 VT300 REPORTS
A DECRSPS sequence can only restore the information from one report at a
time, cursor information or tab stop.
PROGRAMMING TIP: Applications can use DECRSPS to restore the terminal
to a previous state specified in a presentation state report. See the previous
"Cursor Information Report (DECCIR)" and "Tab Stop Report (DECTABSR)"
sections in this chapter.
Available in: VT300 mode
DCS Ps
$
t
D...D
ST
9/0 3/?
2/4
7/4
it.
9/12
where
Ps indicates the format of the data string (D...D). You can use one of the
two following formats for the data string. These formats correspond to the
formats used in the two presentation state reports (DECPSR). Make sure
you use the format of the report you are restoring.
Ps Data String Format
Error, restore ignored.
1 Selects the format of the cursor information report (DECCIR).
2 Selects the format of the tab stop report (DECTABSR).
D...D is a data string that contains the restored information. This string is
identical to the data string used in the report you are restoring — the cur-
sor information report (DECCIR) or tab stop report (DECTABSR).
Example
The following DECRSPS sequence restores tab stops according to the tab stop
report (DECTABSR).
DCS 2 $ u 9; 17; 25; 33; 41; 49; 57; 65; 73 ST
Note that the data string format above is exactly the same as the format for
the tab stop report (DECTABSR).
Notes on DECRSPS
• If there is an invalid value in the DECRSPS sequence, the terminal
ignores the rest of the sequence. This action may leave the terminal
in a partially restored state.
VT300 REPORTS 217
MODE SETTINGS (VT300 MODE ONLY)
The host can request the current settings of any ANSI or DEC private modes.
In response to this request, the terminal returns a report indicating which
modes are set and which are reset. The host can use the information in the
report to save the current mode settings. Later, the host can restore the mode
settings to their saved state.
This operation is useful for applications that need to temporarily change a num-
ber of modes. When the application is finished, it can restore the modes to
their previous state.
The host requests the setting of a mode with a DECRQM sequence. The termi-
nal responds with a DECRPM sequence. The host can then restore a saved
setting with an SM or RM sequence. The following sections describe these
sequences.
Request Mode (DECRQM) — Host To VT300
The host sends this control function to find out if a particular mode is set or
reset. The terminal responds with a report mode function (DECRPM).
There are two versions of the DECRQM function, for ANSI and DEC private
modes.
Requesting ANSI Modes
CSI Pa $ p
9/11 3/? 2/4 7/0
where
Pa indicates the ANSI mode that the host is asking about. Table 12-2 lists
the values for Pa.
Requesting DEC Private Modes
CSI ? Pd $ p
9/11 3/15 3/? 2/4 7/0
where
Pd indicates the DEC private mode the host is asking about. Table 12-3
lists the values for Pd.
218 VT300 REPORTS
Examples
• The following sequences request the setting of some ANSI modes.
Host Request Meaning
CSI 2 $ p What is the current state of keyboard
action mode (KAMI? (KAM = 2)
CSI 4 $ p What is the current state of
insert/replace mode (IRM)? (IRM = 4)
•
The following sequences request the setting of some DEC private
modes.
Host Request Meaning
CSI ? 60 $ p What is the current state of horizontal
cursor coupling mode (DECHCCM)?
(HCCM = 60)
CSI ? 6 $ p What is the current state of origin mode
(DECOM)? (DECOM = 6)
Notes on DECRQM
• A DECRQM sequence can only ask about one mode at a time.
VT300 REPORTS 219
Table 12-2 ANSI Modes for DECRQM. DECRPM, SM, and RM
Mode
Guarded area transfer
Keyboard action
Control representation
Insert/replace
■Erasure
Horizontal editing
Send/receive
Multiple area transfer
Transmit termination
Selected area transfer
Line feed/new line
Mnemonic
Pa
GATM
1
KAM
' 2
CRM*
3
IRM
4
ERM
6
HEM}
10
SRM
12
MATM
15
TTM
16
SATM
■: 1.7
LNM
20
* The host cannot change the setting of CRM You can only change CRM
from set-up. If CRM is set. the terminal ignores DECRQM and most other
control functions. ■
} This control function is permanently reset.
Table 12-3 DEC Private Modes for DECRQM. DECRPM, SM, and RM
Mode
Cursor keys
ANSI
Column
Scrolling
Screen
Origin
Autowrap
Autorepeat
Edit
1 ine transmit
Space compression
field delimiter
Transmit execution
Edit key execution
Print form feed
Printer extent
Mnemonic
DECCKM
DECANM
DECCOLM
DECSCLM
DECSCNM
DECOM
DECAWM
DECARM
DECEDM
DECLTM
DECTEM
DECEKEM
DECPFF
DECPEX
Pd
2
3
4
ft
6
7
8
10
II
DECSCFDM 13
14
16
18
19
220 VT300 REPORTS
Table 12-3 DEC Private Modes for DECRQM, DECRPM, SM, and RM
(Cont)
Mode
Text cursor enable
4010/4014 emulation
National replacement
character set
Graphics expanded print
Graphics print color
Graphics print color syntax
Graphics print background
Graphics rotated print
VT131 transmit
Horizontal cursor coupling-
Vertical cursor coupling
Page cursor coupling
Numeric keypad
Backarrow key
Keyboard usage
Transmit rate limiting
Report Mode (DECRPM) — VT300 To Host
The terminal sends this control function in response to a request mode
(DECRQM) function. DECRPM informs the host whether a certain mode is set
or reset.
PROGRAMMING TIP: Applications can use the information in the DECRPM
report to save the current mode settings. Later, the application can restore the
saved mode settings.
This operation is useful for applications that need to temporarily change some
of the terminal's mode settings. When the application is finished, it can restore
the mode settings that were in effect before the application changed them. You
use the set mode (SM) and reset mode (RM) functions to restore mode settings.
SM and RM are described later in this chapter.
There are two versions of DECRPM, for ANSI and DEC private modes.
Mnemonic
Pd
DECTCEM
25
DECTEK
35
DECNRCM
42
DECGEPM
43
DECGPCM
44
DECGPOS
45
DECGPBM
46
DECGRPM
47
DEC131TM
53
DECHCCM
60
DECVCCM
61
DECPCCM
64
DECNKM
(56
DECBKM
67
DECKBUM
68
DECXRLM
73
VT300 REPORTS 221
Reporting ANSI Modes
CSI Pa ; Ps $ y
9/11 3/? 3/11 3/? 2/4 7/9
where
Pa indicates the ANSI mode the terminal is reporting. Table 12-2 lists the
values for Pa.
Ps indicates the setting of the mode, as follows.
Ps Setting of Mode
Mode not recognized.
1 Set.
2 Reset.
3 Permanently set.
4 Permanently reset.
Reporting DEC Private Modes
CSI ? Pd ; Ps $ y
9/11 3/15 3/? 3/11 3/? 2/4 7/9
where
Pd indicates the DEC private mode the terminal is reporting. Table 12-3
lists the values for Pd.
Ps indicates the setting of the mode. The Ps values are the same as for
the ANSI version above.
Examples
• The following sequences report the setting of some ANSI modes.
VT300 Report Meaning
CSI 2 ; 1 $ y Keyboard action mode (KAM) is
currently set. (KAM = 2, set = 1)
222 VT300 REPORTS
CSI 4 ; 2 $ y Insert/replace mode is currently
reset (IRM). (IRM = 4, reset = 2)
• The following sequences report the setting of some DEC private
modes.
VT300 Report Meaning
CSI ? 60; 1 $ y Horizontal cursor coupling mode is
currently set. (DECHCCM = 60,
set = 1)
CSI ? 6 ; 2 $ y Origin mode (DECOM) is currently
reset. (DECOM = 6, reset = 2)
Notes on DECRPM
• The terminal can only report on one mode at a time.
Restoring Mode Settings (SM and RM)
ANSI and DEC private modes are control functions that have only two set-
tings, set or reset. Soft terminal reset and hard terminal reset affect many
control functions, including some ANSI and DEC private modes.
PROGRAMMING TIP: Applications can use the SM and RM functions to re-
store any number of VT300 modes to a desired state. See the previous "Report
Mode (DECRPM)" section in this chapter for details.
Set Mode (SM) - This control function has two versions. You use the ANSI
version to set one or more ANSI modes. You use the DEC private version to
set one or more DEC private modes. You cannot set ANSI and DEC private
modes with the same SM sequence.
Setting ANSI Modes
CSI Pa
t ...
; Pa
h
9/11 3/?
3/11 ...
3/11 3/?
6/8
where
Pa indicates the ANSI mode to set. Table 12-2 lists Pa values for ANSI
modes. You can use more than one Pa value in a sequence.
VT300 REPORTS 223
Setting DEC Private Modes
CSI ? Pd ; ... ; Pd h
9/11 3/15 3/? 3/11 ... 3/11 3/? 6/8
where
Pd indicates a DEC private mode to set. Table 12-3 lists the Pd values for
DEC private modes. You can use more than one Pd value in a sequence.
Examples
• ANSI Modes
The following sequence sets insert/replace mode (IRM) and erasure
mode (ERM).
CSI 4 ; 6 h
where
4 indicates insert/replace mode.
6 indicates erasure mode.
• DEC Private Modes
The following sequence sets scrolling mode (DECSCLM) and hori-
zontal cursor coupling mode (DECHCCM).
CSI ? 4; 60 h
where
4 indicates scrolling mode.
60 indicates horizontal cursor coupling mode.
Reset Mode (RM) - There are two versions of this control function. You use
the ANSI version to reset one or more ANSI modes. You use the DEC private
version to reset one or more DEC private modes. You cannot reset ANSI and
DEC private modes with the same RM sequence.
Resetting ANSI Modes
CSI Pa
* *••
; Pa
1
9/11 3/?
3/11 ...
3/11 3/?
6/12
where
Pa indicates an ANSI mode to reset. Table 12-2 lists the Pa values for
ANSI modes. You can use more than one Pa value in a sequence.
224 VT300 REPORTS
Resetting DEC Private Modes
where
CSI ? Pd
t ...
; Pd
1
9/11 3/15 3/?
3/11 ...
3/11 3/?
6/12
Pd indicates a DEC private mode to reset. Table 12-3 lists the Pd values
for DEC private modes. You can use more than one Pd value in a
sequence.
Examples
• ANSI Modes
The following sequence resets insert/replace mode (IRM) and erasure
mode (ERM).
CSI 4 ; 6 1
where
4 indicates insert/replace mode.
6 indicates erasure mode.
• DEC Private Modes
The following sequence resets scrolling mode (DECSCLM) and hori-
zontal cursor coupling mode (DECHCCM).
CSI ? 4; 60 1
where
4 indicates scrolling mode.
60 indicates horizontal cursor coupling mode.
CONTROL FUNCTION SETTINGS (VT300 MODE ONLY)
The host can request the current selection or setting of any control function
listed in Table 12-4. In response to this request, the terminal returns a report
indicating the current section or setting of the selected control function. The
host can use the information in the report to save the current setting. Later,
the host can restore the control function to its saved state.
This operation is useful for applications that need to temporarily change a num-
ber of control function settings. When the application is finished, it can restore
the control functions to their previous state.
VT300 REPORTS 225
The host requests the setting of a control function with a DECRQSS sequence.
The terminal responds with a DECRPSS sequence. The host can then restore
the control function, based on the DECRPSS report. The following sections de-
scribe DECRQSS and DECRPSS.
Table 12 4 Control Functions for DECRQSS Requests
Intermediate and
Control Function
Mnemonic
Final Character(s)
Protected fields attributes
DECPRO
Select active status display
DECSASD
$}
Set character attribute
DECSCA
"q
Set conformance level
DECSCL
"P
Bet col'mmss per page
DECSCPP
$!
Set lines per page
DECSLPP
t
Set status line type
DECSSDT
$~
Set top and bottom margins
DECSTBM
r
Set transmit termination
DECTTC
S ; fl ■■''■ : ' : ^
eiiawier" 7 .
Transmit line termination
DECTLTC
\s
character
Select graphic rendition
SCM
m
Request Selection or Setting (DECRQSS) — Host To VT300
The host sends this sequence to ask for the setting of a control function. The
terminal responds with a report selection or setting (DECRPSS) sequence.
DCS $
9/0 2/4
q
7/1
D...D ST
9/12
where
D...D indicates the control function the host is asking about. D...D consists
of the intermediate and/or final characters of the control function re-
quested. Table 12-4 lists the control functions the host can ask about, with
their final characters.
226 VT300 REPORTS
Examples
• The following DECRQSS sequence asks about the select graphic
rendition (SGR) function.
DCS $ q m ST
where
m is the final character of the SGR sequence.
• The following sequence asks about the set columns per page
(DECSCPP) function.
DCS $ q $ | ST
where
$ | are the intermediate and final characters of the DECSCPP
sequence.
Notes on DECRQSS
• A DECRQSS sequence can only ask about one control function at a
time.
Report Selection or Setting (DECRPSS) — VT300 To Host
The terminal sends the host this sequence in response to a request selection or
setting (DECRQSS) sequence. The terminal sends DECRPSS to report the set-
ting of a particular control function.
PROGRAMMING TIP: Applications can use the information in the DECRPSS
report to save the current selections or settings of some control functions.
Later, the application can restore the control functions to their saved state.
This operation is useful for applications that need to temporarily change the
settings of some of the terminal's control functions. When the application is
finished, it can restore the control functions to their previous state.
DCS Ps
$
r
D...D
ST
9/0 3/?
2/4
7/1
9/12
VT300 REPORTS 227
where
Ps indicates whether or not the request from the host is valid.
= host's request is valid.
1 = host's request is invalid.
D...D indicates the current setting of a valid control function that the host
asked about. D...D consists of all the characters in the control function,
except the CSI (9/11) or ESC [ (1/11, 5/11) introducer characters.
Examples
The host requests the setting of the select graphic rendition (SGR)
function. If the current graphic rendition is blinking, reverse, and
invisible, the terminal responds with the following DECRPSS
sequence.
DCS S r ; 5 ; 7 ; 8 m ST
where
; 5 ; 7 ; 8 m are all the characters in the SGR sequence,
except CSI.
The host requests the setting of the set top and bottom margin
function (DECSTBM). If the current top and bottom margins are set
to include the complete screen area, the terminal responds with the
following DECRPSS sequence.
DCS $ r 1 ; 24 r ST
where
1 ; 24 r are all the characters in the DECSTBM sequence, ex-
cept CSI.
The host requests the setting of a function that the terminal does
not recognize. The terminal responds with the following DECRPSS
sequence.
228 VT300 REPORTS
DCSl$rST
The terminal does not send a data string (D...D) to the host when
the terminal receives an invalid request.
SAVING AND RESTORING THE CURSOR STATE
The save cursor function (DECSC) stores many of the terminal's selections and
settings. The restore cursor function (DECRC) restores the terminal to the
state saved by DECSC.
PROGRAMMING TIP: Applications can use DECSC to save the current set-
tings of many modes and control functions. Later, the application can use
DECRC restore the control functions and modes to their saved state.
This operation is useful for applications that need to temporarily change the
settings of some of the terminal's modes and control functions. When the appli-
cation is finished, it can restore the modes and control functions to their pre-
vious state.
Name Sequence Action
Save cursor ESC 7 Saves the following in the terminal's
(DECSC) 1/11 3/7 memory.
• Cursor position
• Visual character attributes
• Character sets (GO, Gl, G2, or G3)
currently in GL and GR
• Wrap flag (autowrap or no autowrap)
• State of origin mode (DECOM)
• Selective erase attribute (DECSCA)
• Any single shift 2 (SS2) or single
shift 3 (SS3) functions sent
Restores the terminal to the state
saved by the save cursor (DECSC)
Restore
ESC 8
cursor
1/11 3/8
(DECRC)
VT300 REPORTS 229
function. If nothing was saved by
DECSC, then DECRC performs the
following actions.
• Moves the cursor to the home
position (upper left of screen).
• Resets origin mode (DECOM).
• Turns all visual character
attributes off (normal setting).
• Turns selective erase attribute
off.
• Maps the ASCII character set into
GL, and the DEC Supplemental
Graphic set into GR.
Notes on DECSC and DECRC
• The terminal maintains a separate DECSC buffer for the main dis-
play and the status line. This feature lets you save a separate oper-
ating state for the main display and the status line.
• DECSC does not save the protection attribute set by start protected
area (SPA) and end protected area (EPA).
WINDOW REPORTS (VT300 MODE ONLY)
The host can ask the terminal how much of the current page is displayed on
the screen at any time. The terminal responds by reporting how much of the
page is on the screen, in terms of lines and columns.
PROGRAMMING TIP: This operation is useful for applications that need to
know the size of the current user window.
Request Displayed Extent (DECRQDE)
The host sends this control function to ask how much of the current page is
displayed on the screen. The terminal responds with a report displayed extent
(DECRPDE) sequence.
CSI " v
9/11 2/2 7/6
Report Displayed Extent (DECRPDE)
The terminal sends this control function in response to a request displayed ex-
tent (DECRQDE) sequence. DECRPDE indicates how much of the current
page is displayed on the screen for the active session.
230 VT300 REPORTS
Remember that the screen can be split into two user windows, one per session.
The user can split the screen horizontally or vertically. DECRPDE indicates
how much of the screen the active session has to display the current page. See
Chapter 8 of Installing and Using the VT330/VT340 Video Terminal for details
on user windows.
CSI
Ph
; Pw; Pml; Pmt; Pmp
//
w
9/11
**
3/11 ** **
2/2
7/7
where
Ph is the number of lines of the current page displayed in the active ses-
sion's window.
Pw is the number of columns of the current page displayed in the active
session's window.
Pml is the number of the current page column displayed in the leftmost
column of the active session's window.
Pmt is the number of the current page line displayed in the top line of the
active session's window.
Pmp is the number of the current page displayed in the active session's
window.
USER-PREFERRED SUPPLEMENTAL SET (DECRQUPSS)
(VT300 MODE ONLY)
The host can ask for the current user-preferred supplemental set. The terminal
responds with the assign user-preferred supplemental set (DECAUPSS) se-
quence (Chapter 5).
PROGRAMMING TIP: This operation is useful for applications that need to
know what supplemental character set the terminal is using.
Host Request (DECRQUPSS)
The host requests the current user-preferred supplemental set by sending the
following sequence.
CSI & u
9/11 2/6 7/5
VT300 REPORTS 231
Terminal Response
The terminal uses the DECAUPSS device control string to report the current
user-preferred supplemental set (Chapter 5). The terminal sends DECAUPSS in
response to a DECRQUPSS sequence. The terminal can send one of the follow-
ing reports.
DCS ! u % 5 ST The user-preferred supplemental set is
DEC Supplemental Graphic.
DCS 1 ! u A ST The user-preferred supplemental set is
ISO Latin-1 supplemental.
232 VT300 REPORTS
SUMMARY
Table 12-5 lists all the sequences described in this chapter.
Table 12-5 Sequences for VT300 Reports
Name Mnemonic Sequence
Primary Device Attributes
Primary DA DA CS1 c or CS1 c
request
(Host to VT300)
Primary DA
response
(VT300 to host)
DA CSI ? Psc; Psl: ... Psn <•
Psc = operati ig level.
61 = level 1 (VT100 family).
62,63 = level 3 (VT300 family)
Psl.
..Psn = extensions.
1
= 132 columns.
2
= printer port.
3
= ReGIS graphics.
4
= sixel graphics.
6
= selective erase.
ri'" : '■'■'■■
1
= soft character set.
8
= user-defined keys.
9
= NRC sets.
13
= lo< i' editing n'odo.
15
= DEC technical set.
16
= locator device port
18
= user windows.
19
= duai sessions.
See Table 12-1 for alias responses.
VT300 REPORTS 233
Table 12-5 Sequences for V'1'300 Reports (Cont)
Name MiiemomV Sixpimifv
Secondary Device Attributes
Secondary DA
E)A request
(Host to VT300)
Secondary
DA response
(VT300 to host)
DA
Device Status Reports
VT300 Operating Status
Request DSR
(Host to VT30G)
Report
(VT300 to host)
DSK
Cursor Position Report
Request. DSR
(Host to VT300I
Report
(VT300 to host)
CPR
CSI > c or CSI > c
CSI > Pp;Pv;Pcc
Pp = identification code.
18 = VT330 terminal.
19 = VT340 terminal.
Pv = firmware version.
Pc = ROM cartridge registration.
CSI 5 n
CSI n
No malfunction.
CSI 3 n
Malfunction.
CSI 6 n
CSI PI: Pc R
PI = line number.
Pc = column number.
234 VT300 REPORTS
Table 12-5 Sequences for VT300 Reports (Cont)
Name Mnemonic Sequence
Extended Cursor Position Report
Request
DSR
CSI ? 6 n
(Host to VT300)
Report
DECXCPR CSI PI; Pc; Pp R
(VT300 to host)
PI = line number.
Pc = column number.
Pp = page number.
Printer Status
Request
DSR
CSI ? 15 n
(Host to VT300)
Report
DSR
CSI ? 13 n
(VT300 to host)
No printer.
CSI ? 10 n
Printer ready.
CSI ? 11 n
Printer not ready.
CSI ? 18 n
Printer busy.
CSI ? 19 n
Printer assigned to other session
UDK Status (VT300 Mode Only)
Request DSR
(Host to VT300)
Report DSR
(VT300 to host)
CSI ? 25 n
CSI ? 20 n
UDKs unlocked.
CSI ? 21 n
UDKs locked.
VT300 REPORTS 235
Table 12 5 Sequences for VT300 Reports (Cont)
Name Mnemonic Sequence
Keyboard Dialect
Request DSR
(Host to VT300)
Report DSR
IVT300 to host)
Locator Device Status (VT300 Mode Only)
Request DSR
(Host to VT300)
Report DSR
( VT300 to host!
CSI ?
26 n
CSI ?
27; Pla: Pst n
Pla
= keyboard dialect.
1
= North, America p.
2
-British.
3
— Flemish.
4
= French Canadian
5
= Danish.
6
= Finnish.
7
= German.
8
= Dutch.
9
= Italian.
10
— Swiss FrencL
11
• Swiss German.
12
■ Swedish.
13
= Norwegian.
14
= French/Belgian
15
= Spanish.
16
= Portuguese.
Pst
= keyboard status.
~ keyboard read]/.
3
= no keyboard.
8
= keyboard busy.
de Or
iy)
CSI?
55 n
CSI?
53 n
No locator device.
CSI?
50 n
Locator device ready.
CSI?
58 n
Locat
or device busy.
236 VT300 REPORTS
Table 12-5 Sequences for \T300 Reports (Cont)
Name Mnemonic Sequence
Locator Device ID (VT300 Mode Only)
Request DSR
(Host to VT300)
Report DSR
(VT300 to host)
CSI ? 56 n
CSI ? 57; n
Unknown device.
CSI ? 57; 1 n
■-:"'■ v.; ■ .' V . :V ':: ; . : ' Digital's mouse,
CSI ? 57; 2 n
Digital's tablet.
Terminal State Reports (VT300 Mode Only)
Request
(Host to VT300)
Request color
table report
Terminal state
report
(VT300 to host)
Color table
report
Restore
DKCKQTSR CSIPsSu
Ps = report requested.
:.;■■■ :: : ■ .. :: ■ : ■ ." - ■ -': ignored. '■ ■ ■'.' . ■
1 = terminal state report.
2 = color table report.
DECRQTSR CSI 2; Ps2 $ u
Ps2 = color coordinate system
= HLS (default)
1 = HLS
2 = RGB
DECTSR DCS 1 $ s D..D < checksums 1 and 2 > ST
■ i; .;: I )...!) ■- . report data. ■ .'■■' ■ '■
DECCTR DCS 2 $ s D...D ST
D...D = color data. (See text.)
DEC RSTS DCS Ps $ p D...D ST
■ . '■ ' Ps = data string format. ^-V ; : ^
■;: v ':■.':. = error.
1 = terminal state report.
2 = color table report.
' : - [ X'^' : . ; ; ; D...D ■-■'■•■ restored data.
VT300 REPORTS 237
Table 12-5 Sequences for VT300 Reports (Cont)
Name Mnemonic Sequence
Presentation State Reports (VT300 Mode Only)
Request
(HosttoVT300l
Cursor
information
report
(VT300 to host!
Tab stop report
(VT300 to host)
Restore
DEC RQ PS Jt CSI Pa $ w
Ps = report requested.
:: s error."
1 = cursor information report.
2 = tab stop report.
DECCIR DCS 1 $ u D...D ST
D..D = data string. See text
. for description.
DECTABSR DCS 2 $ u D...D ST
;; D...D = tab stops.
I) EC RSI'S
Mode Settings (VT300 Mode Only)
Request: mode DECRQM
(HosttoVT300l
DCS Ps $ t D...D ST
Ps = data string format.
= error.
1 = cursor information report.
2 = tab stop report.
D...D = data string.
CSI Pa $ p
Pa = ANSI mode. (Table 12-2)
CSI ? Pd $ p
Pd = DEC private mode.
(Table 12-3)
238 VT300 REPORTS
Table 12-5 Se(
juences for VT30
Reports
(Cont)
Name
Mnemonic
Sequence
Report mode
(VT300 to host)
DECRPM
CSI Pa;
Pa
Ps$y
= ANSI mode. (Table 12-2)
Ps
1
2
3
4
= mode state.
= unknown mode.
= set.
= reset.
— permanently set.
= permanently reset.
Set mode
SM
CSIPa
Pa
... Pa h
= ANSI mode(s). (Table 12-2)
Reset mode
RM
CSI ? Pd; ... Pd h
Pd = DEC private mode(s).
(Table 12-3)
CSI Pa; ... Pa 1
Pa = ANSI mode(s). (Table 1 2-2)
CSI ? Pd; ... Pd 1
Pd = DEC private mode(s).
(Table 12-3)
Control Function Settings (VT300 Mode Only
DECRQSS
Request
(Host to VT300)
Report
(VT300 to host)
DECRPSS
DCS $ q D...D ST
D...D — intermediate and/or final
characters of function.
(Table 12-4)
DCS Ps $ r D...D ST
Ps = 0, valid request.
Ps =1, invalid request.
D...D = intermediate and/or final
characters of function.
(Table 12-4)
VT300 REPORTS 239
Table 12-") Sequences for VT300 Reports (Cont)
Name Mnemonic Sequence
Saving and Restoring the Cursor State
Save cursor DECSC ESC 7 '!:■:; // '' "A ■ ; ' ;
state .
Restore cursor OKCRC ESC 8
state •'. .' -■'..'■' . ■.■'..;
Window Report (VT300 Mode Only)
Request ■ ' DECRQDE CSI " v
(Host to VT3Q0)
Report DECRPDE CSI Ph: Pw; Pml; Pmt; Pmp " w
(VT300 to host) Ph = number of lines.
3^'<: ; X;^ Pw = number of columns.
Pml = first column at left.
Pmt; = top line.
Pmp ■- page number.
User-Preferred Supplemental Set (VT300 Mode)
Request DECRQUPSSCSI & u
(Host to VT30G)
Report DECAUPSS DCS () ! u % 5 ST
(VT300 to host) DEC Supplemental Graphic
DCS i 1 n A ST
: ;: "{ : ':\ : :;;';': "■' : ; ;: - ; -':- '. 77 : : . ^ "■:<: r ; ; ' .■ /■ P^ ISO Latin-1 supplemental ; :
240 VT300 REPORTS
RESETTING THE TERMINAL
13
Soft Terminal Reset (DECSTR), 242
Hard Terminal Reset (RIS), 244
Using RIS with SSU Sessions, 245
Tab Clear (TBC), 245
Summary, 257
This chapter describes how to reset the settings of many VT300 control func-
tions at the same time.
You can also reset your VT300 by using set-up. See Chapter 5 of Installing
and Using the VT330/VT340 Video Terminal for information on using set-up.
There are three control functions you can use to reset the terminal.
Soft terminal reset Selects most of the power-up factory
(DECSTR) factory default settings.
Hard terminal reset Selects the settings stored in NVR
(RIS) memory.
Tab clear (TBC) Clears tab stops.
Soft terminal resets and hard terminal resets affect many control functions,
including some ANSI and DEC private modes. ANSI and DEC private modes
are control functions that have only two settings, set or reset.
241
SOFT TERMINAL RESET (DECSTR)
This control function changes most the terminal's current settings to the
power-up default settings listed in Table 13-1.
Available in: VT300 mode only
CSI !
9/11 2/1
P
7/0
You can also perform a soft terminal reset by selecting Reset Session in the
Set-Up Directory screen. See Chapter 5 of Installing and Using the VT330/
VT340 Video Terminal.
Notes on DECSTR
• DECSTR affects only those functions listed in Table 13-1.
• National replacement character set mode (DECNRCM) is not reset
when you select Reset Session in set-up.
Table 13-1 Soft Terminal Reset {DECSTR) States
Mode
Text cursor enable
Insert/replace
Origin
Autowrap
National replacement
character set
Keyboard action
Numeric keypad
Cursor keys
Mnemonic
State After DECSTR
DECTCEM
Cursor enabled.
1RM
Replace.
DECOM
Absolute (cursor origin at upper
left of screen).
DECAWM
No autowrap.
DECNRCM
Multinational set.
KAM
Unlocked.
DECNKM
Numeric characters.
DECCKM
Normal (arrow keys).
242 RESETTING THE TERMINAL
Table 13-1 Soft Terminal Reset (DECSTR) States (Cont)
Mode
Mnemonic
State After DECSTR
Edit
DECEDM
Interactive.
Edit key execution
DECEKEM
Immediate.
Transmit execution
DECTEM
Immediate.
Erasure
ERM
All characters.
Guarded area transfer
GATM
All characters.
Multiple area transfer
MATM
All selected areas.
Selected area transfer
SATM
All areas.
VT131 transmit
DEC131TM
On (VT131).
Line transmit
DECLTM
Off (page or partial page).
Transmit termination
TTM
Scrolling region.
Other Control Functions
Set top and bottom
margins
DECSTBM
Top margin = 1.
Bottom margin *= page length.
All character sets
GO, Gl, G2,
G3, GL. GR
VT300 default settings.
(DECSTR works only in VT300
mode.)
Select graphic rendition
SGR
Normal rendition.
Select character
attribute
DECSCA
Normal (erasable by DECSEL
and DECSED).
Start selected area
End selected area
SSA
ESA
Cleared.
Cleared.
Start protected area
End protected area
SPA
EPA
Cleared.
Cleared.
Save cursor state
DECSC
Home position with
VT300 defaults.
Assign user-preferred
supplemental set
DECAUPSS
Set selected in set-up.
Select active status
display
DECSASD
Main display (first 24
lines).
RESETTING THE TERMINAL 243
HARD TERMINAL RESET (RIS)
NOTE: Digital does not recommend using RIS to reset the terminal. You
should use a soft terminal reset (DECSTR) instead. RIS usually causes a com-
munication line disconnect and may change the current baud rate settings. The
terminal waits a few seconds before it performs a received RIS function.
This control function causes a nonvolatile memory (NVR) recall to occur. RIS
replaces all set-up features with their saved settings. You can find out what the
current saved settings are by looking at the Saved Settings column on the ter-
minal's different set-up screens. See Chapter 5 of Installing and Using the
VT330/VT340 Video Terminal.
When performing a RIS, the terminal sends XOFF to the host to stop commu-
nication. When the RIS is complete, the terminal sends XON to resume
communication.
The terminal stores these saved settings in NVR memory. The saved setting
for a feature is the same as the factory-default setting, unless you saved a new
setting.
You can also perform a hard reset from the Set-Up Directory screen, by select-
ing Recall Saved Settings.
The RIS sequence is as follows.
ESC c
1/11 6/3
RIS Actions
Sets all features listed on set-up screens to their saved settings.
Causes a communication line disconnect.
Clears user-defined keys for both sessions. (See Chapter 14 for details
on session management.)
Clears the soft character set.
Clears page memory. All data stored in page memory is lost.
Clears the screen.
Returns the cursor to the upper-left corner of the screen.
Sets the select graphic rendition (SGR) function to normal rendition.
244 RESETTING THE TERMINAL
• Sets the independent protection attribute to not protected.
• Selects the default character sets (ASCII in GL, and DEC
Supplemental Graphic in GR).
Using RIS with SSL) Sessions
If you use use Digital's Session Support Utility (Chapter 14) to manage ses-
sions, RIS does not disconnect communications. If SSU is enabled and at least
one session is open, RIS does the following.
• Erases the screen.
• Moves the cursor to the home position.
• Performs a soft terminal reset (DECSTR).
• Resets the current session.
TAB CLEAR (TBC)
This control function clears tab stops.
CSI Ps g
9/11 3/? 6/7
where
Ps indicates the tab stops to clear. Ps has only two values, and 3.
Default: Ps = 0.
or none The terminal only clears the tab stop at the cursor.
3 The terminal clears all tab stops.
RESETTING THE TERMINAL 245
SUMMARY
Table 13-2 lists all the control functions described in this chapter.
Table 13-2 VT300 Reset Sequences
Name
Soft terminal reset*
Hard terminal reset
Tabula ihm clear
Mnemonic
Sequence
DECSTR
CSIIp
RIS
ESCc
Not recommended.
TBC
CSI g
Clear tab at cursor position
CSI 3 g
Cit** jifl tabs.
Available in VT300 node only.
246 RESETTING THE TERMINAL
PART 4
DUAL SESSIONS
SESSION MANAGEMENT
14
Dual Sessions, 249
Two Ways to Manage Sessions, 250
Session Resources, 252
Independent Resources, 252
Shared Resources, 253
Multiple System Communications (MSC), 254
Session Support Utility, 254
SSU Environment, 254
ANSI/ReGIS/Tektronix/VT52 Layer, 255
SSU Layer, 255
XON/XOFF Data Flow Control, 255
Using SSU Software, 255
Selecting Sessions (MSC or SSU Software), 255
Enable Session Command, 256
DUAL SESSIONS
A session is an electronic connection between the terminal and a host system.
The VT300 lets you run two sessions at the same time. Each time you estab-
lish a connection with your host system from the terminal, you open a session
on the terminal.
Dual sessions let you process and view information from two sources at the
same time. You can easily move back and forth between these sessions. You do
not have to end one session before you begin another. You can run the two
sessions on separate host systems or on the same system.
The VT300 maintains a separate context for each session. What you do in one
session does not affect the other session.
249
TWO WAYS TO MANAGE SESSIONS
When you run two sessions at the same time, you need some way to manage
the flow of data to and from each session. For example, suppose a user wants
to switch from session 1 to session 2. The terminal must be able to inform the
host system of the switch, without affecting the normal data flow.
You can use one of two ways to manage sessions on a VT300.
Multiple system communications (MSC)
Session Support Utility
Multiple system communications uses two communication lines between the
terminal and host to run two sessions. Each session uses a separate line. You
can connect the lines to the same host (or terminal server) or two separate
hosts (or terminal servers). Figure 14-1 shows some typical MSC environments.
MSC is basically a hardware solution for session management. MSC is the
same type of system used by terminals that can run only one session. MSC
does not require special programming commands. MSC session management is
transparent to the host. The terminal manages each session locally.
The Session Support Utility uses only one communication line to run two ses-
sions. Usually, you use SSU software to run two sessions on the same host
computer or terminal server. Figure 14-2 shows a typical SSU environment.
SSU software uses a protocol of system-level commands to maintain dual ses-
sions. You can use the commands that best suit your needs.
SSU software differs from MSC in the following ways.
SSU Software
Uses one communication line
for dual sessions.
Uses a set of commands to
control both sessions.
Requires that the host and
terminal recognize SSU
commands.
MSC
Requires two communication
lines, one for each session.
Does not use commands.
Is transparent to the host,
since there are no commands
to recognize.
NOTE: Make sure your system supports SSU software before you use this pro-
tocol. Your host system must be able to interpret and send SSU commands.
250 SESSION MANAGEMENT
The next section describes how the VT300 divides its resources between two
sessions. The rest of the chapter describes the two methods of session manage-
ment, MSC and SSU software.
HOST 1 OR
TERMINAL
SERVER
COMM LINE 1 (SESSION 1)
HOST 2 OR
TERMINAL
SERVER
COMM LINE 2 (SESSION 2)
HOST OR
TERMINAL
SERVER
COMM LINE 1 (SESSION 1)
COMM LINE 2 (SESSION 2)
MA 0087 86
Figure 14-1 Typical MSC Environments
SESSION MANAGEMENT 251
HOST OR
TERMINAL
SERVER
COMM LINE
SESSION 1
SESSION 2
MA-0088-86
Figure 14-2 Typical SSU Environment
SESSION RESOURCES
When you run dual sessions on the terminal, you interact with one session at a
time. This active session has primary access to the terminal's features and re-
sources. The inactive session must wait to use some resources.
This section describes which resources each session can use independently and
which resources they must share.
Independent Resources
The terminal maintains two sets of some features, so each session can use
those features independently. For example, the terminal has two sets of page
memory, one for each session. The terminal has two sets of the following
features.
• Page memory
When you run dual sessions, each session has 72 lines by 80 or 132
columns of page memory.
• ANSI text state
Each session maintains a record of current character sets, text attri-
butes, and pages.
• Status lines
Each session has a status line.
252 SESSION MANAGEMENT
• Set-Up
Each session has its own set-up feature settings.
• Down-line-loadable character set
You can design and load a soft character set for each session.
• User-defined keys (UDKs)
Each session can have a set of UDK definitions. However, the ter-
minal can only store one set of definitions at a time. You can save
the UDK definitions for the current session by using the UDK Set-
up screen. If you do not save the definitions, they are lost when you
turn off the terminal.
• Communication lines
In an MSC environment, each session has a communication line.
• Graphics page memory
Each session has a single page (800 x 480 pixels) for drawing
images.
• ReGIS state
Each session maintains a record of the current ReGIS graphics
state.
• Tektronix 4010/4014 state
Each session maintains a record of the current 4010/4014 state.
• Color map (VT340)
Each session has its own virtual color map. However, the terminal
can only use the active session's color map.
NOTE; If you change the active session's color map. the appear-
ance of the inactive session's color is unpredictable.
Shared Resources
Only one session can use the following features at a time. If session 1 is using
the resource, session 2 must wait until session 1 is finished.
• Screen
You can divide the screen to display data from two sessions at the
same time. However, both sessions must compete for time to update
the screen. See Chapter 8 of Installing and Using the VT330/VT340
Video Terminal for details on dividing the screen into two windows.
• Keyboard
Only the active session can use the keyboard.
SESSION MANAGEMENT 253
• Printer port
Only one session at a time can use the printer port. If session 1 is
using the printer, session 2 must wait until session 1 is finished.
You can assign the printer to a particular session by using set-up, or
by using a print control function (Chapter 11). When you assign the
printer port to a session, you restrict the use of the printer to that
session.
• Locator device port
Only the active session can use the locator device (mouse or graph-
ics tablet) to enter data.
MULTIPLE SYSTEM COMMUNICATIONS (MSC)
Multiple system communications lets you run two sessions without software
support from the host. MSC uses both communication ports on the rear of the
terminal, one port for each session. Each session has a dedicated physical link
to the host.
You can select MSC by using set-up. See Chapter 3 of Installing and Using
The VT330/T340 Video Terminal. You cannot use MSC and SSU software at
the same time.
Unlike SSU software, MSC does not use a system-level protocol to maintain
two sessions. MSC uses two hardwire links to the host.
SESSION SUPPORT UTILITY
SSU software lets the terminal run two sessions over a single communication
line. That is, each session shares the same communication line. SSU is a set of
system-level commands that the terminal and host use to maintain sessions.
NOTE: Make sure your system supports SSU software before you use this pro-
tocol. Your host system must be able to interpret and send SSU commands.
SSU Environment
The VT300 and the host system exchange different types of data at different
levels, called layers. When you use SSU software, there are three basic layers
of data exchange between the terminal and host. These layers have an order of
priority, as follows.
ANSI/ReGIS/Tektronix/VT52 layer
SSU layer
XON/XOFF flow control
254 SESSION MANAGEMENT
ANSI/ReGIS/Tektronix/VT52 Layer - This layer includes all alphanumeric char-
acters as well as text and graphics functions the terminal uses. The alphanu-
meric characters include all characters in the character sets that the terminal
supports. Text functions include such tasks as selecting page format, character
sets, and character attributes (for example, bold, underline, and protected attri-
butes). Graphics functions include the drawing and coloring of images.
SSU Layer - At this layer, the terminal and host exchange SSU commands to
maintain the session environment. This layer connects the terminal to the host,
and controls how the terminal and host switch from session to session. SSU
software can also control the flow of data between the terminal and host at the
session level. However, SSU data flow control is secondary to the XON/XOFF
data flow control.
XON/XOFF Data Flow Control - This layer controls the flow of data between
the terminal and the host. When the terminal's receive buffer is full, this layer
tells the host to stop sending data to the terminal. When the terminal's receive
buffer can accept more data, this layer tells the host resume sending data to
the terminal.
This layer affects both sessions, because it controls the link between the termi-
nal proper and the host. Appendix B describes XON/XOFF flow control in
detail.
Using SSU Software
See Chapter 8 of Installing and Using The VT330/VT340 Video Terminal for
details on using SSU session management.
SELECTING SESSIONS (MSC OR SSU SOFTWARE)
You can select the active session by using the Switch Session key or the enable
session control function.
If session 1 is the active session and you press Switch Session, session 2 be-
comes the active session. Session 1 becomes the inactive session. If your host
system also requires you to log in, you can log in to the second session.
The enable session command works like the Switch Session key. If session 1 is
the active session and the terminal receives the enable session command, ses-
sion 2 becomes the active session. Session 1 becomes the inactive session.
SESSION MANAGEMENT 255
Enable Session Command
This command works with MCS or SSU sessions.
CSI & x
9/11 2/6 7/8
The session receiving the enable session command becomes the active session.
The other session becomes the inactive session.
256 SESSION MANAGEMENT
VT52 MODE CONTROL CODES
A
Entering VT52 Mode, 257
Exiting VT52 Mode, 258
The VT52 mode lets the VT300 terminal operate like a VT52 terminal. You use
VT52 mode with applications designed for the VT52.
NOTE: VT52 mode may not be included in future Digital terminals.
Programmers should only write new software for the ANSI operating mode.
Software should avoid switching indiscriminately between ANSI and VT52
modes. In VT52 mode, the terminal ignores many features and settings used in
the ANSI environment. To avoid confusion, write all new software for the
ANSI operating mode.
Entering VT52 Mode
You use the DECANM control function to change the terminal to the VT52
mode of operation. In VT52 mode, the VT300 acts like a VT52 terminal. This
mode lets you use applications designed for a VT52 terminal.
CSI ? 2 1
9/11 3/15 3/2 6/12
Table A-l lists and describes all the escape sequences you can use when the
terminal is in VT52 mode.
Notes on DECANM
• ANSI private control functions are not available.
• The DEC Supplemental Graphic, ISO Latin-1 supplemental, and
NRC sets are not available.
257
• Cl control characters are not available.
• The ASCII character set defaults to GO.
Exiting VT52 Mode
You can exit VT52 mode by using the following escape sequence.
ESC <
1/11 3/12
When you you exit VT52 mode, the terminal returns to the mode it was in
before entering VT52 mode.
Table A-l VT52 Escape Sequences
Sequence Action
ESC A Cursor up.
ESC B Cursor down.
ESC C Cursor right.
ESC I ) '}:::Hi : Cursor left. :'.'-, ; ; . : .
ESC F Enter graphics mode. ": : '\V '■
ESC G Exit graphics mode.
ESC H Cursor to home position.
ESC I Reverse line feed.
ESC J Erase from cursor to end of screen.
ES( K Erase from cursor to - : vd of line.
ESC Y Pn Move curso; to column Pn.
ESC Z Identify, (host to terminal)
ESC / Z Report, (terminal to host)
ESC = Enter alternate keypad mode.
ESC > Exit alternate keypad (node.
ESC < Exit VT52 mode. (Enter VT100 mode.)
ESC * Enter autoprint mode.
ESC _ Ex!:, ai itoprint :;..ode.
ESC W Enter {winter controller roods.
ESC X Exit printer controller mode.
ESC] Print screen.
ESC V Print the line with the cursor.
258 VT52 MODE CONTROL CODES
COMMUNICATION
B
Character Format, 260
Making Connections, 260
Modem Cables, 261
Null Modem Cables, 261
DECconnect Cabling for 6-Pin DEC-423 Connectors, 261
Connecting the VT300 to Other Digital Products, 262
Locator Devices, 262
Communicating with Non-Digital Systems, 264
Direct-Wired Connections, 264
Connecting Through a Modem, 264
Communicating with IBM Systems, 265
VT300 Communication Ports, 265
25-Pin RS232 Connector, 265
25-Pin Signal Descriptions, 266
DECconnect (DEC-423) 6-Pin Connectors, 269
Comm 1 Port, 270
Comm 2 Port and Printer Port, 270
Modems, 271
Low-Speed Modems, 271
Medium-Speed Modems, 271
High-Speed Modems, 271
Worldwide Modem Protocols, 272
Communications Set-Up Screen, 272
Flow Control Features, 272
Receive XOFF Point, 273
Transmit Flow Control, 273
Transmit Rate Limiting, 273
Character Format Features, 274
259
Character Format, 274
Stop Bits, 274
Modem Features, 275
Modem Control, 275
Modem High Speed, 278
Modem Low Speed, 278
Disconnect Delay, 279
Break, 279
Break Key, 279
Standards and Certification, 280
This appendix describes how the VT300 communicates with a host computer,
modem, or printer. The appendix lists the cables and modems you can use for
different system configurations. The VT300 uses full-duplex, asychronous lines
only. This appendix is important for users with special communication require-
ments, particularly those having non-Digital systems.
CHARACTER FORMAT
The VT300 can send and receive characters in a 7-bit or 8-bit format. The
asynchronous character format consists of a start bit (space), the data bits (1 =
mark, = space), the parity bit (if present) and 1 or 2 stop bits (mark). The
data bits represent a character, with the least significant bits leading.
You can set the parity bit to none, odd, even, space, or mark, using the
Character Format feature in the Communications Set-Up screen.
For more information on the asynchronous character format, see ANSI
X3.15-1976, "American National Standard for bit sequencing of the American
National Standard Code for Information Interchange in Serial-By-Bit Data
Transmission".
MAKING CONNECTIONS
You can order EIA cables from Digital in a variety of lengths, for flexible sys-
tem configuration and expansion. Digital cables provide a minimum shielding
effectiveness of 30db in the 30 through 200 MHz range. You can use these
EIA cables for traditional null modem, modem, and 25-conductor EIA applica-
tions. You can also use EIA cables
• with Digital's DHU11, DHV11, DMZ32, DMF32, and DZSll inter-
face devices.
260 COMMUNICATION
• with terminals and modems.
• as part of the FCC upgrading process for traditional products, such
as Digital's DZ11 and DMR11 modules.
Modem Cables
The BC22E modem cable uses 16 conductors. The cable has a 25-pin plug on
one end and a 25-pin socket on the other. You can use the BC22E cable as
• a connection between the 25-pin RS232 port on the VT300 and any
of Digital's modems (such as the DF03 and DF224).
• a serial line extension cord.
• a direct connection between the VT300 and many of Digital's com-
munication options.
The BC22E cable is available in the following lengths.
BC22E-10/AB 10 feet BC-22E-100/AB 100 feet
BC-22E-25/AB 25 feet BC-22E-200/AB 200 feet
BC-22E-50/AB 50 feet BC-22E-250/AB 250 feet
When style is an issue, you can use the BCC14 cable.
BCC14-10/AB 10 feet
BCC14-25/AB 25 feet
BCC14-50/AB 50 feet
Null Modem Cables
The BC22D null modem cable has 16 conductors, and a 25-pin socket on both
ends. This cable is available in the following lengths.
BC22D-10/AB 10 feet BC22D-100/AB 100 feet
BC22D-25/AB 25 feet BC22D-200/AB 200 feet
BC22D-50/AB 50 feet BC22D-250/AB 250 feet
DECconnect Cabling for 6-Pin DEC-423 Connectors
The VT300 has 6-pin DEC-423 connectors to take advantage of DECconnect
terminal cabling. Based on the RS423 standard, DEC-423 cabling lets you run
your terminal at higher speeds and over longer distances than the RS232 stan-
dards. Where RS232 signaling limits cable runs to 50 feet, DEC-423 lets you
use cable runs of up to 1000 feet from the terminal to the host system.
COMMUNICATION 261
DEC-423 provides enhanced electrical overstress (EOS) and electrostatic dis-
charge (ESD) protection that reduces computer equipment damage from static
discharge, lightning, or ac power impulse.
Adapters and converters are available that let you use DEC-423 and the new
DECconnect office cabling with older terminals, personal computers, and
printers.
The DECconnect office cable is a 6-conductor flat cable used to connect the
VT300 to the DECconnect wallplate. Each end of tne office cable has Digital's
proprietary MMP (modified modular plug). The plug is similar to the modular
plugs used in telephone equipment, but is modified to prevent accidental con-
nection of the DEC-423 cable into the phone jack.
The following DECconnect cables, adapters and converters are available.
BC16E-10/DA 10 foot DECconnect office cable
BC16E-25/DA 25 foot DECconnect office cable
BC16E-50/DA 50 foot DECconnect office cable
H8572 Extender with MMJ on both ends
H8571-A MMJ to DB-25S adapter
H8571-B MMJ to DB-9S adapter
H3 105 Active converter — RS232 to DEC-423
To extend your DECconnect connection, you can use the following
configuration.
[TERMINAL]<— BC16E— >[H8572]<— BC16E— >[HOST SYSTEM]
Connecting the VT300 to Other Digital Products
Table B-l lists the cables to use when connecting the VT300 to a terminal
server, modem, or statistical multiplexer. Table B-2 lists the cables and adapt-
ers to use when connecting the VT300 to a printer.
Locator Devices
The VT300 has a 7-pin locator device connector on the rear of the terminal.
The connector supports a locator device (mouse or graphics tablet). The VT300
supports the following Digital locator devices.
VSXXX-AA mouse VSXXX-AB graphics tablet
262 COMMUNICATION
Table B-l Cables to Terminal Servers, Modems, and Statistical Multiplexers
To Connect the VT300 to...
Terminal Servers
DECS A (LAT-11)
DSRVA-AA/DA (DECserver 100)
Statistical Multiplexers
DFM04-AA/AB DFM 1 2-AA/AB
DFM08-AA/AB DFM16-AA/AB
■VAX Systems
OMF32 '' .
DMZ32-M/AB
n/32
PDP-11 Unibus Systems
DHU11
DZ11
DL11
PDP-11 Q-bus Systems
DHV11 DLV.J]
DZQ11 DZV11
DLVE1
Modems
DF112-AA
DF124-AA
DF224-AA
Table B-2
Cables to Digital P
Printer
Cable/Adapter
LA12
BC16E-10/DA
LA50
H8571-A
LA210
LA75
BC16E-10/DA
LN03 series
BC16E-10/DA
HS571-A
LQP series
BC16E-10/DA
H8571-A
Use This Cable...
BC22D
BC22E, BCC04, or BCC14
BC22D
BC22D
BC22D
BC22E
Description
10 foot DECconnect office cable
MMJ to DB-25S adapter
10 foot DECconnect office cable
10 foot DECconnect office cable
MMJ to DB-25S adapter
10 foot DECconnect office cable
MMJ to DB-25S adapter
COMMUNICATION 263
COMMUNICATING WITH NON-DIGITAL SYSTEMS
This section describes how to use the VT300 with non-Digital environments.
The most conservative approach to communicating with a non-Digital system is
to use the 25-pin RS232 serial port with a suitable cable and recall the factory-
default settings from set-up. Then set the following features in set-up.
Set-Up Screen
Feature
Setting
Global Set-Up
On-Line/Local
on-line
General Set-Up
Terminal Mode
VT100
Device Attributes Response
VT100
Display Set-Up
Scrolling
jump
Communications Set-Up
Transmit Speed
(Match your host.)
Receive Speed
receive = transmit
Receive XOFF Point
(Match your host.)
Transmit Flow Control
disabled
Character Format
(Match your host.)
Stop Bits
(Match your host.)
Disconnect Delay
no disconnect
Local Echo
disabled
Keyboard Set-Up
Compose
disabled
You select the Character Format in the Communications Set-Up screen. Digital
recommends that you try the 7-bit settings first, starting with "7 bits, mark
parity". For speeds above 110 bits per second, select 1 stop bit. For a speed of
110 or lower, select 2 stop bits.
Direct-Wired Connections
Follow these basic rules to make a direct-wired connection to a non-Digital
host.
1. Match the terminal's baud rate to that of your host. If you are
unsure, try 9600 baud first and work down.
2. Match the terminal's character format to that of your host. If you are
unsure, try "7-bits, mark parity".
Connecting Through A Modem
Follow these basic rules to connect to a non-Digital host via a modem.
1. Match the terminal's baud rate with that of your modem. If you are
unsure, try 300 baud first and work up.
264 COMMUNICATION
2. Match the terminal's character format with that of your modem.
3. Set the Transmit Flow Control feature in the Communications Set-Up
screen to "disabled".
4. Set the Receive XOFF Point feature in the Communications Set-Up
screen to "never".
Steps 3 and 4 ensure that the VT300 receives some characters without halting
after receiving an XOFF from the host. Character processing in the VT300 oc-
curs at about 9400 bits per second. To prevent data loss, set the terminal's
transmit and receive rates lower than 9400 bits per second to prevent data
loss. With this configuration, you cannot use the Hold Session or Local Print
functions.
Communicating with IBM Systems
Some IBM systems do not echo characters back to the terminal screen. These
systems generally operate in half-duplex environments. If the characters that
you type do not appear on the screen, check to make sure the host is operating
correctly. If it is, set the Local Echo feature in the Global Set-Up screen to
"enabled".
The VT300 communicates asynchronously and generally conforms to ANSI
X3.64 environments only. It does not support IBM traits such as 3270 emula-
tion, SNA, Bisync, SDLC, or HDLC.
VT300 COMMUNICATION PORTS
The VT300 has two communication ports, Comml and Comm2. The Comml
port has two connectors, a 25-pin RS232 connector and a 6-pin DEC-423 con-
nector. The Comm2 port has one 6-pin DEC-423 connector. Only one port is
active at a time. You use the Global Set-Up screen to select which port is
active.
25-Pin RS232 Connector
This DB25 serial port accepts a variety of modems meeting national and inter-
national standards. Table B-3 lists the signals for the 25-pin RS232 connector.
The voltages acceptable at this port comply with EIA standard RS423,
"Electrical Characteristics of Unbalanced Voltage Digital Interface Circuits".
COMMUNICATION 265
Table B-3
EIA Interface Signals for the 25-Pin RS232 Connector
Circuit
Pin
Source
Name
Function
CCITT/EIA/DIN
1
Not used
2
VT300
TXD
Transmitted data
103/BA/D1
3
Modem
RXD
Received data
104/BB/D2
4
VT300
RTS
Request to send
105/CA/S2
5
Mode
CTS
Clear to send
106/CB/M2
6
Modem
DSR
Data set ready
107/CC/M1
7
—
SGND
Signal ground
102/AB/E2
8
Modem
RLSD
Receive line
signal detector
109/CF/M5
9 to 11
Not used
12
Modem
SPDI
Speed mode indicator
112/CI
13 to 19
Not used
20
VT300
DTR
Data terminal ready
108.2/CD/S1.2
21 to 22
Not used
23
VT300
SPDS
Speed select
111/CH/S4
24 to 25
Not used
25-Pin Signal Descriptions
Transmitted Data — TXD (Pin 2 BA/103/D1)
Data on this circuit represents the serially encoded characters that the VT300
transmits. This circuit is at mark state (-) during stop bits between characters,
and when data is not being transmitted. This signal is also supported on the
6-pin DEC-423 connectors.
Received Data — RXD (Pin 3 BB/104/D2)
Data on this circuit represents the serially encoded characters the VT300 re-
ceives. This signal is supported on the 25-pin RS232 and 6-pin DEC-423
connectors.
In modem control mode 1 (Communications Set-Up), the terminal ignores re-
ceived characters if RLSD is unasserted. This is an implementation of mark
carrier clamping.
266 COMMUNICATION
In modem control mode 2, the terminal receives characters even if RLSD is
unasserted. This implementation permits use of V.25 bis compatible autodial
modems in modem control mode 2. You do not have to set modem control
mode to "disabled" to access the autodial functions.
When mode control mode is disabled (data leads only), the terminal processes
received data regardless of the state of the control lines.
Request To Send — RTS (Pin 4 CA/105/S2)
Asserting RTS may put the modem in the transmit mode. In transmit mode,
the modem asserts CTS. When the terminal is in local mode, RTS is deas-
serted. This signal is not supported on the 6-pin DEC-423 connectors.
NOTE: On full-duplex modems without RTS inputs, CTS is asserted by the
modem whenever it is ready for transmission.
Clear To Send — CTS (Pin 5 CB/106/M2)
The modem asserts CTS when it is ready to receive data. This signal is not
supported on the 6-pin DEC-423 connectors.
The data can be in one of two forms: a command to the modem if off-line (DSR
deasserted), or transmitted data to the host if on-line (DSR asserted).
Data Terminal Ready — DTR (Pin 20 CD/108.2/S1.2)
The VT300 asserts DTR whenever it is ready to send or receive on the active
port. Asserting DTR allows a modem to connect and maintain the connection.
Deasserting DTR prevents the modem from completing a started call, and
causes an already established call to disconnect. A deassertion of 50ms causes
a disconnect to occur. This signal is also supported on the 6-pin DEC-423
connectors.
With auto-answer modems, the terminal must assert DTR before the modem
can answer a call. If DTR is deasserted, the modem does not answer the call. If
a connection exists, DTR remains asserted whether the terminal is on-line, lo-
cal, or making the transition. Switching between on-line and local modes does
not cause a disconnect.
The VT300 drops DTR when one of the following functions is performed.
Recall Saved Settings (Set-Up Directory)
Recall Factory Default Settings (Set-Up Directory)
Shift-Break
Power-up self-test
Hard terminal reset (RIS)
COMMUNICATION 267
Data Set Ready — DSR (Pin 6 CC/107/M1)
Asserting DSR indicates
• the modem is in data mode and connected to the communications
channel;
• the answer tone is finished, and you are being charged by the PTT;
• the modem is ready to exchange control signals in order to begin
data transmission and reception.
This signal is also supported the 6-pin DEC-423 connectors.
If DSR becomes unasserted before DTR during a call, the terminal disconnects
the call. The terminal considers any new assertion of DSR a new call. If (1) the
VT300 is connected to a modem that is off, or (2) DSR becomes an open cir-
cuit, then the terminal interprets the condition as a deassertion. You can check
the state of the DSR input on the indicator status line.
If DSR is deasserted 220 ms after DTR is deasserted, the VT300 does nothing
because the modem has already disconnected.
If DSR is still asserted 220 ms after DTR is deasserted, DTR from the VT300
remains deasserted for at least 2 seconds to assure that the modem is
disconnected.
When DSR is unasserted and modem control mode 2 is selected, an off-line
state exists. (See "Modem Control Mode 2" in this appendix.} In this state,
you can interact with an intelligent modem for such actions as entering phone
numbers and changing modem set-up.
When DSR is asserted in modem control mode 2, the modem, terminal, and
host system are ready for communication to a remote host.
Receive Line Signal Detector — RLSD (Pin 8 CF/109/M5)
This signal is also called carrier detect. The modem asserts RLSD when the
received signal is of sufficient amplitude. This signal is not supported on the
6-pin DEC-423 connectors.
The unasserted condition of RLSD indicates (1) there is no received signal, or
(2) the signal is unsuitable for demodulation.
Speed Indicator — SPDI (Pin 12 CI/112/M4)
This signal comes from the modem. SPDI lets modems control the terminal's
transmit and receive rates. This signal is not supported on the 6-pin RS423
connector.
268 COMMUNICATION
7/ modem control mode 1 or 2 is enabled (Communications Set-Up)
If SPDI is unasserted, the terminal's transmit and receive speeds are set to the
current Modem Low Speed setting in Communications Set-Up.
If SPDI is asserted, the transmit and receive speeds are set to the current
Modem High Speed setting in Communications Set-Up.
Table B-4 shows common settings for a wide variety of modems.
Table B-4
Common Speed Settings Foi
SPDI
SPDI
Asserted
Unasserted
AT&T 212
1200
300
AT&T 103
300
n/aor HO
V.22
1200
600
V.22 bis
2400
1200
V.26 ter
2400
1200
V.32
4800
2400
V.32
9600
4800
Speed Select — SPDS (Pin 23 CH/111/S4)
SPDS comes from the terminal. If the VT300's baud rate is greater than or
equal to 1200, the speed select rate is high. If the baud rate is less than 1200,
the speed select rate is low.
When this signal is enabled at the modem, the terminal can select modem
speed by controlling EIA pin 23.
NOTE: The DF224 modem is factory-set to ignore this pin and make the termi-
nal receive speed information from the speed indicator signal (SPDI 12/CI/112I
M4).
DECconnect (DEC-423) 6-Pin Connectors
The 6-pin connectors for Comml and Comm2 provide limited modem support.
The DTR output and DSR input are supported on this connector. Transmit
ground for transmit data and DTR is isolated from receive ground used for
receive data and DSR.
Using Modems on DEC-423 Connectors
The DEC-423 connector does not support the following signals: RTS, CTS,
RLSD, SPDI, and SPDS. Because these signals are not supported, you cannot
use the modem control modes (Communications Set-Up). When running a mo-
dem on the 6-pin connector, set modem control mode to "disabled".
COMMUNICATION 269
DEC-423 Signals
Pin Signal Name
Mnemonic
1 Data terminal ready*
DTR (ready out)
2 Transmitted data*
TXD (TX + )
3 Transmitted data return
(TX-)
4 Received data return
(RX-)
5 Received data*
RXD (RX +)
6 Data set ready*
DSR (ready in)
* See the signal description for the 25-pin RS232 connector.
Pin 6 is on the right end of the connector, above the locking tab.
6-Pin Connector (tab facing down)
12 3 4 5 6
Comm 1 Port
The host 1 port has a 25-pin RS232 connector and a 6-pin DEC-423 connector.
You can connect a communication line to each connector. Then you can use the
Comml Port feature in Global Set-Up to switch between full modem control
support ("RS232" setting) and DECconnect ("DEC-423" setting).
This port supports communication speeds of 75, 110, 150, 300, 600, 1200,
2400, 4800, 9600 (the default), and 19,200 bits per second. You can use differ-
ent transmit and receive speeds.
If you switch from RS232 (25-pin port) to DEC-423 (DECconnect), the VT300
disconnects the RS232 port. If you switch from DEC-423 to RS232, the VT300
disconnects the DEC-423 connector (deasserting DTR).
Comm 2 Port and Printer Port
These ports work the same as the Comm 1 DEC-423 connector. They support
the same communication speeds (9600 default).
Comm 2 lets you transmit and receive at different speeds. The printer port
does not. Use only the " Receive = Transmit" setting for the printer port.
270 COMMUNICATION
MODEMS
The VT300 supports asynchronous, full-duplex modems. The VT300 does not
support half-duplex modems or synchronous modems.
Low-Speed Modems (300 to 1200 Baud)
In low-speed communication, 1200 baud is now a more common speed than 300
baud. Digital's DF03 and DF112 modems support 1200 baud communication.
The standard protocols for 1200 baud communication are AT&T 212A in North
America, and CCITT V.22 in Europe and Japan. The two protocols are not
compatible at the modulation level. The Racal Vadic 3400 protocol is also in
use and may be less susceptible to noisy line environments. Most data center
modems that use the Racal Vadic protocol also support AT&T 212A. These
three protocols are full duplex and work over ordinary phone lines.
The standard protocols for to 300 baud communication are AT&T 103 in
North America, and CCITT V.21 in Europe and Japan. These protocols are not
compatible at the modulation level.
Medium-Speed Modems (2400 Baud)
The worldwide standard protocol for 2400 baud communication is CCITT V.22
bis. This protocol is full-duplex over dial-up phone lines. It adjusts to both the
sending and receiving characteristics of the line conditions at the beginning of
communication. The V.22 bis protocol requires much cleaner, noise-free tele-
phone lines than 1200 baud protocols. Many long-distance circuits cannot sup-
port communication at 2400 baud using V.22 bis.
V.22 bis modems are supposed to use the 1200 baud V.21 protocol if the line is
too noisy, but some units may not. If you want to connect at 1200 baud with a
V.22 bis modem, you must determine whether it is set for AT&T 2 12 A or V.22
bis.
High-Speed Modems (Over 2400 Baud)
The CCITT V.26 ter protocol also runs at 2400 baud. This protocol is techni-
cally different from V.22 bis and handles noisier phone lines. V.26 ter is also
much more expensive, using echo canceling rather than frequency division mul-
tiplexing for full-duplex operation. V.26 ter modems are more compatible with
the higher speed V.32 4800 and 9600 baud modems and could be a better in-
vestment in the long run.
COMMUNICATION 271
Worldwide Modem Protocols
Table B-5 shows many modem protocols used throughout the world.
Table B 5 Worldwide Modem Protocols '
Duplex
Modem
Bits/
True
Full/
A sync,
Dial-up/
Protocol
Second
Rate
Half
MM
Syne
Leased
Area
AT&T
103
300
300
F
FSK
A
D
North America
201
2400
1200
11
PSK
S
D/L
North America
202
1200
300
II
—
A
I)
North America
208
4800
1600
H/F*
PSK
S
D/L
North America
209
9600
2400
H/F*
—
S
L
North Amerirji
212A
1200
600
F
PSK
A/S
D
North America
CCITT
V.21
300
300
F
FSK
A
D
Europe. Japan
V.22
1200
600
F
QAM
A/S
D
Europe. Japan
V.22 bis
2400
600
F'. ■
QAM
A-'S
D
world
V.23
1200
600
F
PSK
A/S
D
Europe, Japan
V.26 ter
2400
1 200
F
—
A/S
D
world
V.29
9600
2400
H/F*
—
S
D/L
world
V.32
4800
2400
F
—
A/S
D
world
. * 2/4 wire . . ... . .
COMMUNICATIONS SET-UP SCREEN
Chapter 5 of Installing and Using the VT330/VT340 Video Terminal describes
the features you can set from the Communications Set-Up screen. The follow-
ing sections provide more details about some of the features that affect data
flow control, character format, and modems.
FLOW CONTROL
The VT300 can operate at transmission speeds of up to 19,200 baud. However,
the terminal may not be able to keep up with the incoming data. The terminal
stores incoming characters in its 1024 byte receive buffer, and processes them
on a first-in/first-out basis.
272 COMMUNICATION
When the buffer begins to fill, the terminal sends an XOFF (DC3) signal to the
host. This signal tells the host to suspend its transmission to the terminal.
When the host stops transmitting, the terminal processes most of the charac-
ters in of the receive buffer. When the buffer is nearly empty, the terminal
sends an XON (DC1) signal to the host to resume transmission.
Receive XOFF Point
Values: 64 (default), 256, 512, never
64 (default), 256, 512
The VT300 sends XOFF to the host when its input buffer contains 64, 256, or
512 bytes. The terminal stores all received characters except NUL, XON, and
XOFF in the input buffer before further processing. NUL is discarded.
There are three XOFF points and one XON point.
Never
The VT300 temporarily stores all characters except NUL in the input buffer
before further processing. NUL is discarded when received. The host system
must prevent overflow of the input buffer.
Operating systems that do not recognize XON/XOFF signals can send fill char-
acters. The only valid fill character is NUL (hexadecimal, decimal, or octal).
Transmit Flow Control
Values: XON/XOFF (default), disabled
When you select XON/XOFF, the VT300 recognizes received XON and XOFF
characters from the host. When the terminal receives XOFF, it stops sending
any codes except XOFF and XON. The Wait indicator on the keyboard also
turns on. The terminal resumes transmission when it receives XON.
If you select the disabled setting, pressing Ctrl-S sends XOFF and pressing
Ctrl-Q sends an XON.
Transmit Rate Limiting
When you enable this feature, the VT300 limits the rate at which it sends data
to the host to 150 to 180 characters per second, with even spacing. Some host
systems can only keep up with the relatively slow input of keys typed manually
from the keyboard. Rate limiting simulates this condition and reduces the inter-
rupt burden on the host.
When disabled, the terminal sends all messages and keystrokes as fast as pos-
sible, limited only by the current Transmit Speed setting.
COMMUNICATION 273
DECXRLM Control Function
Software can control the Transmit Rate Limiting feature through the
DECXRLM control function. DECXRLM has two settings.
Set (limited)
CSI
9/11
?
3/15
7
3/7
3
3/3
h
6/8
Reset (unlimited)
CSI
9/11
?
3/15
7
3/7
3
3/3
1
6/12
CHARACTER FORMAT FEATURES
You can select the character format and number of stop bits in the
Communications Set-Up screen.
Character Format
Values:
8 bits, no parity (default) 7 bits, no parity
8 bits, even parity 7 bits, even parity
8 bits, odd parity 7 bits, odd parity
8 bits, even, no check 7 bits, mark parity
8 bits, odd, no check 7 bits, space parity
7 bits, even, no check
7 bits, odd, no check
If you select a "no check" setting, the VT300 ignores the receive parity bit.
If you enable parity error detection, the terminal converts characters with re-
ceived parity errors to the SUB character. This character appears on the
screen as an error indication (backward question mark).
If you select 8 data bits, the eighth bit is when you use 7-bit character sets.
In this case, the terminal ignores the bit when received.
Stop Bits
You can specify 1 or 2 stop bits with any of the available baud rates or data
bit/parity combinations. This feature is required for asynchronous terminals
connected to data networks as specified in CCITT recommendations X.20bis.
As a general rule, use 2 stop bits for baud rates below 300. Otherwise, use 1
stop bit.
274 COMMUNICATION
MODEM FEATURES
Modem Control
Values: disabled (data leads only, default)
mode 1 (VT220)
mode 2
This feature selects how the VT300 uses modem control signals.
Disabled (Data Leads Only)
The terminal ignores all modem control signals, and communicates using the
data leads only.
DTR is always asserted except when you initiate a disconnect
sequence. RTS is always asserted. The terminal ignores DSR, CTS, RLSD and
SPDI.
Modem Control Mode 1 (VT220)
Included for compatibility with the VT220, this mode requires the handshake
exchanges of DTR/DSR, and CTS/RTS before any data transmission or recep-
tion begins.
Connection
The VT300 waits for the exchage of DTR/DSR and RTS/CTS.
If the Auto-Answerback feature is enabled, the terminal sends the answerback
message after the assertion of DSR, CTS, and RLSD. CTS is the last line
checked.
After making a connection, the VT300 performs the following operations to en-
sure that it is ready to send and receive.
1. Unlocks the keyboard, if it is locked.
2. Clears any transmit in progress on the active port.
3. Clears all buffers associated with the active port.
4. Clears the "XOFF sent" and "XOFF received" state of the active
port.
After receiving the carrier tone, the modem asserts CD, and data transmission
and reception can begin.
COMMUNICATION 275
Disconnection
A disconnect sequence begins when any of the following events occur.
• You press Shift-Break.
NOTE: You can disable the Break key in the Keyboard Set-Up
screen.
• You select Recall Saved Settings, or Recall Factory Default Settings
from the Set-Up Directory. This disconnects the active session's
line.
• You turn off the terminal.
• The VT300 loses the DSR, CTS, or RLSD signal.
• After establishing a connection on the Comml 25-pin line, the
VT300 loses the RLSD for longer than 2 seconds (or 60 ms).
In modem control mode 2, RLSD (CD) is ignored.
• The VT300 receives a hard terminal reset (RIS).
Modem Control Mode 2
In this mode, there are two operating states for the modem, "Off Line" and
"On Line". The modem indicates which mode is current on the status line with
the DSR indicator. If DSR is unasserted, then the modem is off-line.
Otherwise, it is on-line.
The VT300 only supports the hardware handshaking of the V.25 bis protocol.
The VT300 hardware does not support the ring indicator (RI) signal. The termi-
nal does not support those states in which a transition is based on the RI
signal.
Also, the VT300 does not parse the commands shown in CCITT Table 3/V.25
bis. The modem must parse these commands.
276 COMMUNICATION
VT300 V.25 Bis State Diagram
VT300 STATE
STATE #1
DTE_NOT_READY
DTR=OFF DSR=OFF
CTS=OFF
VT300 STATE 1
STATE #2
DTE_READY
DTR=ON DSR=OFF
CTS=OFF
VT300 STATE
2
STATE #'c
(
DTE-DCE
DIALOG
DTR=ON
DSR=
=OFF
CTS=ON
VT300 STATE 2
STATE #4
CALL_ESTABLISH
DTR=ON DSR=OFF
CTS=ON
VT300 STATE 3
STATE #5
ANSWER_TONE DET
DTR=ON DSR=OFF
CTS=OFF
VT300 STATE 4
STATE #6
CALL_CONNECTED
DTR=ON DSR=ON
CTS=OFF
VT300 STATE 4
STATE #12
DATA_TRANSFER
DTR=ON DSR=ON
CTS=X
VT300 V.25 Bis Connection
DTE
DCE
DTR
DSR
CD:
-<D CRQ<cr»-
-<H <XON»-
-<E Ready<crlf»-
-<K Attached<crlf»-
RTS:. A
CTS: B
(A) Power-up. The terminal asserts RTS when power is applied.
(B) The modem asserts CTS.
(C) Self-test has completed. The terminal asserts DTR.
(D) You type CRQ (Call Request) from keyboard, or press a previously loaded
UDK.
(E) The modem receives and parses this character string.
(F) The modem deasserts CTS.
(G) The modem asserts DSR.
(H) The modem asserts CD.
(I) The modem asserts CTS.
(J) The terminal sends an XON.
COMMUNICATION 277
VT300 V.25 Bis Disconnection
DTE:-<A logoff >
DCE: <B logged out at > <G Disconnected-
CD : c
DSR
CTS
DTR
D_
(A) You log off the system.
(B) The host sends (and VT300 displays) the log off message. After the log
off message, the host starts a disconnect procedure.
(C) The modem deasserts carrier detect, (computer hangs up).
(D) The modem deasserts DSR.
(E) The modem deasserts CTS.
(F) As a result of the modem dropping DSR, the terminal drops DTR.
(G) The modem sends the message "Disconnected" to the terminal.
(H) The minimum DTR deassertion time has been met. The terminal asserts
DTR.
(I) The modem asserts CTS.
Modem High Speed
Values: ignore (default), 300,600,1200,2400,4800,9600,19.2K
When you enable modem control, the VT300 can use the speed indicator signal
(SI) from the modem to select the communication rate. The Modem High Speed
feature sets the rate used when the speed indicator line is "on".
If you set this feature to "ignore", the terminal uses its regular transmit and
receive speeds.
Modem Low Speed
Values: ignore (default), 300,600,1200,2400,4800,9600,19.2K
This feature is similar to the Modem High Speed feature, but sets the commu-
nication rate when the speed indicator line is "off". If you set Modem Low
Speed to "ignore", the terminaluses its regular transmit and receive speed.
Modems that use a baud rate slower than 300 cannot use this feature (auto-
matic speed selection).
278 COMMUNICATION
Disconnect Delay
Values: 2 seconds (default), 60 ms, no disconnect
When you enable modem control, the Disconnect Delay feature determines the
time the VT300 takes to disconnect communication after losing the received
line signal detect (RLSD).
All countries except the United Kingdom should use the "2 seconds" setting.
The 60 ms delay is for use in the United Kingdom.
If you select "no disconnect" and the VT300 detects a loss of carrier, the ter-
minal ignores RLSD (CD) after the beginning of the connection.
If you try to disconnect and reconnect the line, the VT300 checks if RLSD is
asserted before granting the connection. After it is connected, the terminal ig-
nores the loss of carrier. In this case, the disconnect should be done when the
DSR signal goes off.
BREAK
A break condition is the occurrence of a continuous space on a communication
line for greater than one character time. A break consists of a 275 ± 25 ms
space condition on the transmit data line during transmission. In local mode,
the VT300 does not send the break character. The break (space) condition is
separated from any later mark-to-space transition by at least 100 ms.
Break Key
The Break key has four functions. You can enable or disable the Break key in
the Keyboard Set-Up screen.
• Pressing Break sends a break function to the host.
• Pressing Shift-Break causes a disconnect to occur.
• Pressing Ctrl-Break sends the answerback message to the host.
• When running dual sessions, the VT300 ignores any breaks it re-
ceives. However, one or more error characters (backward question
marks) may appear on the screen.
COMMUNICATION 279
STANDARDS AND CERTIFICATION
Standards
CCITT Recommendation V.25-bis (reference document CCITT AP VIII-
43-E) with limitation to hardware handshaking.
EIA STANDARD EIA-232-D Interface Between Data Terminal
Equipment and Data Communications Equipment Employing Serial
Binary Data Interchange.
V.24 List of Definitions for Interchange Circuits between Data Terminal
Equipment and Data Circuit-Terminating Equipment 1984.
V.28 Electrical Characteristics for Unbalanced Double-Current
Interchange Circuits 1984.
The VT300 can connect to all modems conforming to the following standards:
AT&T 103, 113, and 212A modems or plug compatibles including Digital's
DF02, DF03, DF112, DF124, DF224 and DF242 modems.
Certification
United Kingdom (U.K.) attended operation only
GPO, German ZZF V.21, V.22, V.22 bis, V.23, X.20 bis modems and
data service units.
280 COMMUNICATION
COMPATIBILITY
WITH OTHER DIGITAL TERMINALS
C
New
Software
Feature
VT330
VT340 VT220 VT240 VT241 Required
Character Attributes
Blink
Y
Y
Y
Y
Y
N
Bold
Y
Y
Y
Y
Y
N
Double high
Y
Y
Y
Y
Y
N
Double wide
Y
Y
Y
Y
Y
N
Invisible
Y
Y
N
N
N
Y
Protection
Y
Y
N
N
N
Y
Reverse
Y
Y
Y
Y
Y
N
Transmission
Y
Y
N
N
N
Y
Underline
Y
Y
Y
Y
Y
N
Character Sets
DEC Multinational
Y
Y
Y
Y
Y
N
DEC Special Graphic
Y
Y
Y
Y
Y
N
Down-line-loadable
Y
Y
Y
Y
Y
N
ISO Latin-1
Y
Y
N
N
N
Y
National replacement sets
Y
Y
Y
Y
Y
N
Color
Color palette
N/A
4096
N/A
N/A
64
Y
Colors in display
N/A
16
N/A
N/A
4
Y
Shades of gray
4
16
N/A
N/A
4
N
281
Feature
Communication
Baud rate up to 19.2 K
Composite video output
Optional integral modem
Printer port
Bidirectional
Serial ports
New-
Software
VT330 VT340 VT220 VT240 VT241 Required
Y
Y
Y
Y
Y
N
N
N
Y
Y
Y
N
N
N
Y
Y
Y
N
N
MMJ
2
2
N
RS232
Y
Y
Y
Y
Y
N
20 milliamp
N
N
Y
Y
Y
N
Compatibility
VT52
Y
Y
Y
Y
Y
N
VT100
Y
Y
Y
Y
Y
N
VT125
Y
Y
N
N
N
N
VT131
Y
Y
N
N
N
N
VT220
Y
Y
Y
Y
Y
N
VT240
Y
Y
N
Y
Y
N
VT241
N
Y
N
N
Y
N
Components
Number
2
2
2
3
3
N
Fan
N
N
N
Y
Y
N
Firmware cartridge
Y
Y
N
N
N
N
Display Features
Character cell
80 columns
10x20
10x20
10x10
10x10
10x10
N
132 columns
6x20
6x20
6x10
6x10
6x10
N
Display size (inches)
14
13
12
12
13
N
Display type (flat or convex)
F
C
C
C
C
N
Nonglare screen
Etch
Etch
Coat.
Coat.
Coat.
N
Pixel aspect ratio
Square
Square Rect.
Rect.
Rect.
N
Rear panel cable cover
Y
Y
N
N
N
N
282 COMPATIBILITY WITH OTHER DIGITAL TERMINALS
Feature
Display Features (cont)
Resolution
Vertical
Horizontal
Tilt-swivel base
Dual Sessions
2 cables
1 cable (SSU)
Graphics
Cursors
Rubber band box
Rubber band line
Cross hair
Performance
ReGIS
Sixels
Tektronix 4010/4014
Local Editing
ANSI X3.64 block mode
VT131 block mode
Off-Screen Memory
132-column lines
Characters
Characters per session
Multiple page formats
25th Status Line
Host
Local
New
Software
VT330 VT340 VT220 VT240 VT241 Required
500
500
240
240
240
N
800
800
800
800
800
N
Y
Y
N
N
N
N
Y
Y
N
N
N
N
Y
Y
N
N
N
Y
Y
Y
N/A
N
N
Y
Y
Y
N/A
N
N
Y
Y
Y
N/A
Y
Y
N
Fast
Fast
N/A
Slow
Slow
N
Fast
Fast
N/A
Slow
Slow
N
Fast
Fast
N/A
Slow
Slow
N
Y
Y
N
N
N
N
Y
Y
N
N
N
N
Y
144
144
19008
19008
9504
9504
N/A
N/A
N/A
Y
Y
N/A
N/A
N/A
Y
Y
N
N
N
Y
Y
Y
N
N
N
N
COMPATIBILITY WITH OTHER DIGITAL TERMINALS 283
New
Software
Feature VT330 VT340 VT220 VT240 VT241 Required
Set-Up Features
Color map editor Y Y N N N N
Full screen set-up mode Y Y N N N N
User-defined key editor Y Y N N N N
Other Features
Host processing through Y Y Y Y Y N
printer support
Mouse/tablet support Y Y N N N Y
local processing
Terminal state inquiry Y Y N N N Y
284 COMPATIBILITY WITH OTHER DIGITAL TERMINALS
GLOSSARY
Active position
The location in page memory where the next typed character will appear. The
cursor indicates the active position.
Announcer
A control function that prepares the terminal for the type of data used by a
certain application. The VT300 supports three ANSI conformance levels that
select the type of data used. These conformance levels are based on the ANSI
standard Dp Ans X3. 134.1.
ANSI
American National Standards Institute
ANSI character types
There are two types of ANSI characters, graphic and control.
Graphic characters are alphanumeric characters that you can display on the
screen. These characters include letters, numbers, punctuation, and any other
characters you can display.
Control characters are characters you do not usually display. They make the
terminal perform specific functions in data communication and text processing.
Carriage return <CR), form feed (FF), and escape (ESC) are examples of control
characters.
ANSI partial page
In local editing mode, all the characters on a page, from the beginning of a
selected area to the cursor.
285
Application
A computer program designed to perform a specific task, such as a word pro-
cessing. Applications are usually coded using high-level programming lan-
guages, such as FORTRAN or Pascal.
Autorepeat
A VT300 feature that makes most keys send their character repeatedly when
you hold the key down. You can turn the autorepeat feature on and off by
using the Keyboard Set-Up screen or the DECARM control function (Chapter
11).
Auxiliary keypad
A group of keys on the right side of the VT300 keyboard that can send num-
bers and punctuation marks, or special control functions defined by an applica-
tion (Chapters 3 and 11).
Baud rate
The speed at which the terminal communicates with the host system or a
printer. The baud rate is measured in bits per second.
Bit
Binary digit. The smallest unit of storable information in a digital machine. A
bit can assume one of two values, (on) or 1 (off).
Bitmap
Random access memory used to store a bit-encoded representation of an image
displayed on the monitor screen. The VT330 uses a 2-plane bitmap, where each
pixel on the screen is represented by 2 bits.
Block
In edit mode, a section of edited data the terminal sends from the terminal's
page memory to the host system.
Block editing
See local editing.
Character cell
The pixel area on the screen that the terminal uses to display a single graphic
character. The VT300 uses a 10 x 20 pixel character cell for each graphic
character.
286 GLOSSARY
Character encoding
All terminals and computers encode information as binary digits, or bits. Older
systems use 7 bits to encode each character. Newer systems such as the
VT300 use 8 bits, which provide more codes. The newer systems can also use
the 7-bit codes.
The VT300 uses an 8-bit character encoding system and a 7-bit code extension
technique.
Character coding format
There are two types of character coding formats, 7-bit and 8-bit.
The 7-bit coding format uses 7 bits to store each character in the terminal's
memory. The ASCII character set uses a 7-bit coding format.
The 8-bit coding format uses 8 bits to store each character in the terminal's
memory. The DEC Supplemental Graphic character set uses an 8-bit format.
Character set
There are two types of character sets, hard and soft.
A hard character set is any one of the terminal's built-in character sets. Hard
character sets in the VT300 include the ASCII, DEC Supplemental Graphic,
ISO Latin-1 supplemental graphic, DEC Special Graphic, Nation Replacement
Character (NRC), and DEC Technical.
A soft character set is any character set that you define using a DECDLD
device control string (Chapter 5). Soft character sets are also called down-line-
loadable sets and dynamically redefinable sets.
Code table
A list of all characters in a character set with their codes. Most standard char-
acter sets put similar characters into groups, so they have similar codes. A
code table lets you see groups of characters and their relative codes clearly.
Column
A vertical row of character positions on the screen. You can display 80- or 132-
column lines.
GLOSSARY 287
Compose sequence
A series of keystrokes you can use to display a character that does not appear
on any single key. Compose sequences start with the Compose Character key.
See Installing and Using the VT330/VT340 Video Terminal for details.
Context
The operating information for a session. For example, the settings of set-up
features are part of a session's context. The terminal maintains a separate con-
text for each session.
Control characters
Characters that make the terminal or host system perform specific functions in
data communications and text processing. The terminal usually does not dis-
play control characters. The VT300 uses two groups of control characters CO
and CI.
CO (control zero) and C1 (control one) characters
The VT300 uses the ANSI and ISO definitions for the functions of CO and CI
controls.
CO control characters are in postions 0/0 through 0/15 in the left half (GL) of
the 8-bit code table. You can use CO characters directly in a 7- or 8-bit environ-
ment.
CI control characters are in positions 8/0 through 9/15 in the right half (GR) of
the 8-bit code table. You can use Cl characters directly in an 8-bit environ-
ment. CI controls can be used in a 7-bit environment as ESC Final escape
sequences.
Control functions
Commands you use in your applications to make the terminal perform special
functions. These functions range from the simple — editing data — to the com-
plex — reporting on the terminal's state. Control functions include control
characters, device control strings, control sequences, and escape sequences.
Control sequence
Any control function that begins with the Cl CSI control character.
Coupled cursor
A cursor that appears to pull the user window through the page. When the
cursor tries to move beyond the borders of the user window, it pans in that
288 GLOSSARY
direction to keep the cursor visible. If the user window is the complete screen,
the cursor looks like it is connected, or coupled, to the screen.
Cursor
A displayed box or underscore that indicates the active position in page mem-
ory. The default cursor is a blinking box. You can select other cursor
characters.
DA
Device attributes. A report the terminal can provide to the host on request. A
DA report can provide the host with information about the terminal such as
conformance level, basic features, identification code, and firmware version
level. The host can use this information to adjust the computing environment
and make the best use of the terminal's features.
DA exchange
An exchange between the host and VT300 in which the host requests and the
terminal responds with basic information about the terminal, such as the termi-
nal's identification code.
Data flow control
The method used to synchronize communication between the terminal and the
host system.
Data processing keys
Keys that have three or four characters on the top of their keycap, rather than
the normal two. Every keyboard except the North American keyboard has
some data processing keys.
DCS
Introduces device control strings. DCS is a CI control character in position 9/0
of the 8-bit code table. You can use the equivalent 7-bit escape sequence ESC P
when coding for a 7-bit environment.
DEC private control functions
Private sequences created by Digital for specific families of products. ANSI se-
quences and DEC private sequences follow ANSI standards for character codes.
GLOSSARY 289
In this manual, private control functions created by Digital have the prefix
DEC in their mnemonic name. For example, horizontal cursor coupling mode
has the mnemonic DECHCCM. All other control functions are ANSI
sequences.
DEC Multinational character set
The factory default character set for the VT300. The left half of this set is the
the 7-bit ASCII set (with CO control characters), stored in the GL table. The
right half is the 8-bit DEC Supplemental Graphic set (with Cl control charac-
ters), stored in the GR table.
DEC Special Graphic character set
This 7-bit character set has 94 graphic characters. Most of the graphic charac-
ters are also in the ASCII character set. The other graphic characters include
special symbols and line segments. Another name for this character set is the
VT100 line drawing character set.
DEC Supplemental Graphic character set
This 8-bit character set has 94 graphic characters. The graphic characters in-
clude letters with accents and diacritical marks, used in many European lan-
guages. There are also special symbols, such as currency signs.
DEC Technical character set
This 7-bit character set has 94 graphic characters. The DEC Technical set has
characters and symbols often used in technical applications, such as schematic
and logic diagrams.
Default
A standard factory setting for a terminal feature. The VT300 uses default set-
tings for features and control functions, until you change the settings. Many
control functions use default values for parameters. If you omit a value, the
terminal uses the default value.
Designate
Assign a character set to one of the terminal's four logical sets, GO through
G4. This is the first of two steps in selecting a character set for use. The sec-
ond step is mapping the character set.
290 GLOSSARY
Device control string (DCS)
A special form of control function you can use for such operations as down-line-
loading character sets or defining user-defined keys. Device control strings be-
gin with the DCS control character.
Diacritical marks
Marks or symbols that indicate a change in the standard pronunciation of a
letter. Examples of dicritics are acute accent ('), grave accent ('), and tilde 0-
On the VT300, you use diacritical marks in two-stroke compose sequences.
Display
The area of the video screen where the terminal can present visible data.
Display controls mode
A special operating mode that lets you display control codes as graphic charac-
ters, when you want to debug your applications. In this mode, the terminal
does not perform control functions.
Down-line-load
Move data from the host system to the terminal. For example, you can down-
line-load a soft character set into the terminal.
Down-line-loadable (soft) character set
A character set you can load into the VT300 from the host system. The charac-
ter set can have 96 graphic characters. You can design your own soft character
set. You can use the set in the GL or GR table. The terminal stores soft char-
acters in its DRCS buffer. When you turn off the terminal, the soft characters
are lost.
DRCS
Dynamically redefinable character set. See down-line-loadable character set.
DSR
Device status report. The host system sends a DSR request to ask the termi-
nal for the operating status of six terminal features, such as VT300 operating
status and cursor position.
GLOSSARY 291
DTR
Data terminal ready signal. The state of this signal indicates the status of the
printer port.
Dual sessions
A mode in which you can run two sessions at the same time. If you connect
your VT300 to two systems, you can run a session on each system at the same
time.
Echo
To display characters on the screen, in addition to sending them to the host.
Either the host or the terminal can echo characters.
Edit mode
A mode of operation in which the terminal stores the information you type,
rather than sending it immediately to the host system. You decide when to
send your edited data to the host system. This mode requires host software
support.
Editing keypad
The group of 10 keys {including the arrow keys) to the right of the main key-
pad. Table 3-1 lists the codes sent by the editing keys, and Table 3-2 lists the
codes sent by the arrow keys. Normally, you use the arrow keys to control the
cursor on the screen.
Eligible character fields
Areas in page memory that the terminal can send to the host system in edit
mode. Eligible characters are also called selected characters.
Emulation
A method that lets you use the VT300 like other Digital terminals.
End-of-block character
An optional character sent by the terminal at the end of a block transmission,
in edit mode.
292 GLOSSARY
Environment
The coding scheme a system uses to encode characters. Today, most systems
use an 8-bit coding scheme, where each character of data is represented by an
8-bit binary code. The VT300 can operate in a 7- or 8-bit environment.
ESC
The escape character. Introduces escape sequences.
Escape sequences
Control functions that begin with the CO ESC character.
Firmware
All commands and control functions that are built into the terminal, such as
the editing functions.
Font
A set of graphic characters, all of one size and style.
Full-cell fonts
A font that can individually address all pixels in a cell. Usually, text fonts can-
not individually address all pixels.
Graphic left (GL) table
The left half of the terminal's in-use table. The GL table can store up to 94
graphic characters for immediate use. You can store characters in the 2/1
through 7/14 range of character positions. You can use GL codes in 7-bit or
8-bit environments.
Graphic right (GR) table
The right half of the terminal's in-use table. The GR table can store up to 96
graphic characters for immediate use. You can store characters in the 10/1
through 15/15 range of character positions. Some 8-bit character sets only use
94 of these GR codes. You can use GR codes only in an 8-bit environment.
Graphic characters
Characters you can display on a video screen. Graphic characters include let-
ters, numbers, punctuation, and any other characters you can display.
GLOSSARY 293
Graphic rendition
The appearance of a display character, including all of its visual character attri-
butes. You use the select graphic rendition (SGR) control function to select vi-
sual character attributes.
Graphics
Pictures, graphs, and other images that can appear on the terminal's screen.
Graphics are different from text, and the terminal uses a special mode of op-
eration to display graphics.
Hard character set
One of six character sets built into the VT300, such as the ASCII and DEC
Supplemental Graphic sets.
Hard reset
A control function that resets many of the terminal's features to a group of
saved settings. You can perform a hard reset by selecting Recall Saved
Settings in the Set-Up Directory.
HLS
The hue, lightness, and saturation color coordinate system. HLS is one of two
universal systems for specifying colors. The other one is RGB.
Home cursor position
Usually the upper-left corner of the screen. However, home position can also be
the upper-left corner of the scrolling region (that is, the area within the mar-
gins). See "Origin Mode (DECOM)" in Chapter 6.
Host
The computer or terminal server that the terminal communicates with.
Independent protection
A style of character protection that lets you protect areas of page memory,
independent of any visual character attributes. Compare with visual attribute
protection.
294 GLOSSARY
In-use table
The area in the terminal's memory that stores the character set(s) the terminal
is currently using. The in-use table is comprised of the GL and GR logical
tables.
Interactive mode
A mode in which the terminal immediately sends all typed data to the host
system. This is the usual mode of operation for the VT300. You can also select
edit mode.
ISO
International Standards Organization (ISO).
ISO Latin Alphabet Nr 1 supplemental set
This 8-bit character set has 96 graphic characters. The graphic characters are
similar to those in the DEC Supplemental Graphic set. The ISO Latin-1 set
includes letters with accents and diacritical marks, used in many European lan-
guages. It also has other special symbols, not included in the DEC
Supplemental Graphic set. The ISO Latin-1 set is specified in the ISO standard
ISO 8859.1.
Layers
The different levels of data exchange between the VT300 and the host system.
When you use SSU, there are three basic layers of data exchange between the
terminal and host: ANSI/ReGIS/Tektronix/VT52, SSU, and XON/XOFF flow
control.
Line attribute
The visual attributes for a complete display line on the screen.
Local
An operating state where data entered at the keyboard is sent to the screen,
but not the host. The terminal stores data received from the host, until you put
the terminal back on-line.
Locking shift
A control function used to map a designated character set into the terminal's
in-use table as GL or GR. When you use a locking shift, the character set
remains in GL or GR until you use another locking shift.
GLOSSARY 295
Map
Move a designated character set into the terminal's in-use table as GL or GR.
Mapping is the second of two steps in selecting a character set for use. The
first step is designating the character set. After a set is mapped, it is available
from the keyboard.
Margins
See scrolling margins.
Mnemonic
An abbreviated name for a control character or control function. For example,
CR is the mnemonic for the carriage return control character.
MSC
See multiple system communications.
Multiple system communications
A method for managing sessions, using a separate communication line for each
session. The other method for managing sessions is Digital's Session Support
Utility (SSU).
National replacement character sets (NRCs)
A general name for a class of 7-bit, 94-character sets created for different lan-
guages and dialects. The VT300 has 12 NRC sets for many European lan-
guages. The NRC sets are based on ISO standard 646.
NVR
Nonvolatile RAM (random access memory).
On-line
An operating state of the terminal in which the terminal can communicate with
a host system. The terminal sends data entered at the keyboard to the host.
The terminal displays data received from the host on the screen.
Operating modes
Levels of conformance that the VT300 offers.
The VT300 has two major operating modes, VT300 and VT100. You can select
each mode from the keyboard via set-up, or from the host via control codes.
296 GLOSSARY
The VT300 uses standard ANSI functions in all operating modes, except VT52
mode. See Chapter 1.
Origin
The home cursor position on the screen. You can set the home position at the
upper-left of the screen or within the scrolling margins.
Page
A section of the terminal's page memory. Each page has left, right, top, and
bottom scrolling margins. You can define the size and layout of a page by using
set-up features or control functions.
Page format
The size and number of pages in the terminal's page memory. You can arrange
page memory into 1, 2, 3, 4, or 6 pages, depending on whether you use single
or dual sessions. You can also define the margins of a page.
Page memory
A storage area in the VT300 for displayable text. The size of this memory is
equal to 144 display lines by 80 or 132 display columns. You can divide this
memory into one or more pages. The amount of page memory available de-
pends on whether you use single or dual sessions.
Parameter characters
Characters in a control function that define the action and/or limits of that
function.
Partial page marker
An invisible marker that defines the position of the last character sent to the
host on a VT1S1 partial page. The partial page marker applies only in edit
mode.
Pixel
Picture element. The smallest unit of display on the video screen. All graphic
characters are displayed with pixels.
Port
A connector on the rear of the terminal that lets the VT300 communicate with
another device or host computer.
GLOSSARY 297
Presentation state report
A VT300 report that indicates the settings of the terminal's character attri-
butes and cursor, or the settings of its tab stops.
Protected characters
Positions in page memory that cannot be changed, erased, or moved with con-
trol functions, under certain conditions. There are two styles of character pro-
tection available, independent protection and visual attribute protection.
Report
Operating information that the terminal provides the host system. The VT300
can provide the host with report information such as identification (type of ter-
minal), cursor state, operating status, conformance level (1, 2, or 3), and
extensions.
Reset
(1) To change the terminal's operating features to their default or saved set-
tings. (2) To change the setting of an ANSI or DEC private mode to its reset
state.
Reset state
One of two possible settings for an ANSI or DEC private mode. Modes are
control functions that have only two settings.
Restore
To set the terminal to the latest saved operating state. Restoring the terminal
is not the same as resetting the terminal. See reset.
RIS
Reset to initial state.
RGB
The red, green, and blue color coordinate system. RGB is one of two universal
systems for specifying colors. The other one is HLS.
ROM cartridge
A read only memory cartridge that stores much of the terminal's firmware. The
cartridge is installed at the rear of the terminal. The cartridge must be in-
stalled for the terminal to operate.
298 GLOSSARY
Scrolling
Moving data between the scrolling margins of a page. Data scrolled past the
margins is lost from the terminal's page memory.
Scrolling margins
The top, bottom, left, and right boundaries on a page, beyond which data can-
not be written or scrolled.
Selected field
A group of characters defined as eligible to be sent to the host in edit mode.
Session
An electronic connection between between the terminal and host.
Session Support Utility
Digital's software protocol for managing two VT300 sessions over one commu-
nication line. The other method for managing sessions is multiple system com-
munications (MSC).
Set-up
A series of display screens that list the terminal's operating features. Each
screen lists a group of features, such as communications or printing. You can
examine and change the current settings. For example, you can select the
transmit or receive speeds, page size, and type of session management.
Installing and Using the VT330/VT340 Video Terminal describes how to use
set-up.
Single shift
A control character (SS2 or SS3) used to map a designated charge er set into
the terminal's in-use table one character only. You use a single shift when you
want to display the next character from a different character set. A single shift
maps the G2 or G3 set into GL. The character set is active for only one char-
acter, then the terminal returns to the previous character set in GL.
Sixel
A column of 6 pixels on the screen. When you load a soft character set into the
terminal, you use sixel data to code each character.
GLOSSARY 299
Soft character sets
See down-line-loadable (soft) character sets.
Space compression
A method of sending data in which the terminal omits unused character spaces
in edit mode.
ST
String terminator character. ST is a Cl control character. You can use the
equivalent 7-bit sequence ESC \ (1/11, 5/12) when coding for a 7-bit
environment.
Status line
A line of text that appears on line 25 of the screen. There are three possible
status line states: indicator (default), host-writable, and none.
The indicator status line displays operating information about the terminal.
This indicator status line appears in reverse video. The host-writable status line
displays information provided by an application. When set to "none", the status
line is black.
Terminal state report
A report that indicates the entire state of the terminal except for user-defined
key definitions and the current soft character set.
Top-row function keys
The 20 keys (Fl through F20) on the top row of the keyboard. The first five
keys — Hold Session, Local Print, Set-Up, Switch Session, and Break — are
predefined function keys. You can define the function of the other 15 keys
when they are shifted. See user-defined keys.
Typewriter keys
The keys on the main keypad.
User-defined keys
The 15 keys on the top row of the keyboard that you can define to send se-
lected characters or control functions. You can program these keys with a
DECUDK device control string, or you can define these keys from set-up. The
15 keys are F6 through F14, Do, Help, F17 through F20. To use a user-defined
key, you must press Shift-defined key.
300 GLOSSARY
UDKs
User-defined keys.
User-preferred supplemental set
A standby set you use to provide general access to the supplemental set you
use most. You can select this set to be ISO Latin-1 supplemental or DEC
Supplemental Graphic. You can select the user-preferred set in set-up or with a
DECAUPSS control function.
Visual attribute protection
A style of character protection for applications that require strict compatibility
with the VT131 terminal. Visual attribute protection is only available in edit
mode (DECEDM). Visual character protection applies to characters with the
same visual character attribute.
Visual character attribute
A quality assigned to a graphic character that highlights the way the character
appears on the screen, without changing the actual character. For example, the
bold character attribute makes a character appear brighter on the screen.
VT131 partial page
In local editing mode, all characters on a page between the partial page marker
and the cursor.
7-bit code extension technique
A method for expressing 8-bit control characters as 7-bit escape sequences.
GLOSSARY 301
Control Function Index
This index lists all VT300 control functions. The index has three sections. You
can find a function by
• name
page 303
• mnemonic
page 309
• function
page 314
BY NAME
— A—
ANSI conformance levels — 80
ANSI mode off (VT52 mode) DECANM 257
Assign printer to active session — 185
Assign user-preferred supplemental set DECAUPSS .... 80
used to report the supplemental set 231
Autoprint mode — 183
Autorepeat mode DECARM 172
Autowrapmode DECAWM 172
— B—
Backarrow key mode (delete key) DECBKM 170
Control Function Index 303
— c—
Color table report DECCTR 207
Column mode (Not recommended; see DECSCPP.) . . .DECCOLM 106
Cursor backward CUB 162
Cursor down CUD 163
Cursor forward CUF 162
Cursor information report DECCIR 210
Cursor keys mode DECCKM 173
Cursor position CUP 162
Cursor position report CPR 202
Cursor up CUU 162
— D—
Delete character DCH 121
Delete line DL 120
Designating character sets SCS 73
Device attributes DA 196
primary DA 197
secondary DA 199
Device status reports DSR 201
cursor position report CPR 202
extended cursor position report DECXCPR .... 202
keyboard dialect — 203
locator device port — 204
printer port — 202
user-defined keys — 203
VT3 00 operating status — 201
Double-width, double-height line DECDHL 116
Double-width, single-height line DECDWL 116
Down-line-loading soft characters DECDLD 90
used to clear a soft set 101
— E—
Edit key execution mode DECEKEM .... 136
Edit mode DECEDM 13
Enable session — 256
End protected area EPA 128
End selected area ESA 143
Erase character ECH 124
304 Control Function Index
Erase in display ED 122
Erase in line EL 123
Erasure mode ERM 119
Extended cursor position report DECXCPR 202
Guarded area transfer mode GATM 141
NOTE: See Volume 2, Chapter 16 for the following graphics printing
functions.
Graphics expanded print mode DECGEPM . . Vol. 2
Graphics print background mode DECGPBM. . . Vol. 2
Graphics print color mode DECGPCM . . . Vol. 2
Graphics print color syntax DECGPCS . . . Vol. 2
Graphics rotated print mode DECGRPM . . .Vol.2
Graphics to host — Vol. 2
Graphics to printer — Vol. 2
— H—
Hard terminal reset RIS 244
Horizontal and vertical position (See CUP. | HVP 162
Horizontal cursor coupling mode DECHCCM .... 165
— I—
Insert character ICH 122
Insert line IL 121
Insert/replace mode IRM 119
— K—
Keyboard action mode KAM 170
Keyboard usage mode DECKBUM 175
Keypad application mode DECKPAM .... 173
Keypad numeric mode DECKPNM 173
Control Function Index 305
_L—
Line feed/new line mode LNM 171
Line transmit mode DECLTM 138
Locking shift GO LSO 78
Locking shift Gl LSI 78
Locking shift Gl, right LS1R 78
Locking shift G2 LS2 78
Locking shift G2, right LS2R 78
Locking shift G3 LS3 78
Locking shift G3, right LS3R 78
— M—
Mapping character sets — 76
Media copy commands MC 182
Multiple area transfer mode MATM 143
— N—
National replacement character set mode DECNRCM 70
Next page NP 109
Numeric keypad mode DECNKM 174
— o—
Origin mode DECOM 108
— P—
Page cursor coupling mode DECPCCM .... 166
Page position absolute PPA 110
Page position backward PPB 110
Page position relative PPR m
Pan down (scroll up) SU 163
Pan left (scroll right) SR 164
Pan right (scroll left) SL 164
Pan up (scroll down) SD 163
Preceding page PP 109
Print all pages — 184
Print composed main display — 184
Print cursor line — 184
Print form feed mode DECPFF 181
306 Control Function Index
Print page — !83
Printer controller mode — 183
Printer extent mode DECPEX 181
Protected fields attribute DECPRO 129
— R—
Release printer — 185
Report displayed extent DECRPDE 230
Reportmode DECRPM 221
Report selection or setting DECRPSS 227
Request displayed extent DECRQDE 230
Request mode DECRQM 218
Request presentation report DECRQPSR . . . .210
Request selection or setting DECRQSS 226
Request terminal state report DECRQTSR .... 206
Requesting the user-preferred supplemental set.. DECRQUPSS . . .231
Reset mode (for ANSI and DEC private modes) RM 224
Restore cursor DECRC 229
Restore presentation state DECRSPS 216
Restore terminal state DECRSTS 208
Save cursor DECSC 229
Screen mode DECSCNM 187
Scrolling mode DECSCLM .... 187
Select active status display DECSASD 189
Select character protection attribute DECSCA 127
Select graphic rendition (visual attributes).... SGR 115
Select status line type DECSSDT 189
Selected area transfer mode SATM 142
Selecting an operating level DECSCL 67
Selective erase in display DECSED 124
Selective erase in line DECSEL 125
Send/receive mode (local echo) SRM 186
Sending 7-bit CI controls S7C1T 69
Sending 8-bit CI controls S8C1T 69
Set columns per page — recommended DECSCPP 106
Set lines per page DECSLPP 107
Set mode (for ANSI and DEC private modes) SM 223
Set top and bottom margins DECSTBM 108
Control Function Index 307
Set transmit state STS 148
Set transmit termination character DECTTC 144
Single shift G2 SS2 79
Single shift G3 SS3 79
Single-width line DECSWL 116
Soft terminal reset DECSTR 242
Space compression mode DECSCFDM. . . . 147
Start printer-to-host session — 184
Start protected area SPA 128
Start selected area SSA 143
Stop printer-to-host session — 184
— T—
Tab clear TBC 245
Tab stop report DECTABSR .... 216
Terminal identification DECID 200
Terminal state report DECTSR 207
Text cursor enable mode DECTCEM .... 161
Transmit execution mode DECTEM 148
Transmit line termination characters DECTLTC 146
Transmit mode DECXMIT 149
Transmit rate limiting mode DECXRLM .... 273
Transmit termination mode TTM 139
— U—
User-defined keys DECUDK 175
— V—
VTlOOmode — 66
VT1 31 transmit mode DEC131TM 140
VT300mode — 66
Vertical cursor coupling mode DECVCCM 165
Visual attribute protection (VT1 31 style) — See DECPRO.
308 Control Function Index
BY MNEMONIC
—A—
ANSI conformance levels
80
— c—
CPR Cursor position report 202
CUB Cursor backward 162
CUD Cursor down 163
CUF Cursor forward 162
CUP Cursor position 162
CUU Cursor up 162
— D-
DA.
DCH
DEC131TM .
DECANM . ,
DECARM .
DECAUPSS
DECAWM .
DECBKM .
DECCIR. .
DECCKM .
DECCOLM
DECCTR .
DECDHL .
DECDLD .
DECDWL .
DECEDM .
DECEKEM
Device attributes 196
primary 197
secondary 199
Delete character 121
VT1 31 transmit mode 140
ANSI mode off (VT52 mode) 257
Autorepeat mode 172
Assign user-preferred supplemental set 80
used to report the supplemental set 231
Autowrap mode 172
Backarrow key mode (delete key) 170
Cursor information report 210
Cursor keys mode 173
Column mode (Not recommended; see DECSCPP.) 106
Color table report 207
Double-width, double-height line 116
Down-line-loading soft characters 90
used to clear a soft set 101
Double-width, single-height line 116
Edit mode I 36
Edit key execution mode 136
NOTE: See Volume 2, Chapter 16 for the following graphics printing functions.
DECGEPM . . Graphics expanded print mode Vol. 2
DECGPBM . . Graphics print background mode Vol. 2
DECGPCM . . Graphics print color mode Vol.2
Control Function Index 309
DECOPCS.
DECGRPM
DECHCCM .
DECID
DECKBUM . .
DECKPAM . .
DECKPNM . .
DECLTM . . .
DECNKM . . .
DECNRCM . .
DECOM . . . .
DECPCCM . .
DECPEX . . .
DECPFF. . . .
DECPRO . . .
DECRC . . . .
DECRPDE . .
DECRPM . . .
DECRPSS. . .
DECRQDE . .
DECRQM . . .
DECRQPSR. .
DECRQSS. . .
DECRQTSR. .
DECRQUPSS .
DECRSPS
DECRSTS
DECSASD.
DECSC .
DECSCA
DECSCFDM
DECSCL . .
DECSCLM .
DECSCNM .
DECSCPP. .
DECSED . .
DECSEL . .
DECSLPP. .
DECSSDT. .
Graphics print color syntax Vol.2
Graphics rotated print mode Vol. 2
Graphics to host Vol. 2
Graphics to printer Vol. 2
Horizontal cursor coupling mode 165
Terminal identification 200
Keyboard usage mode 175
Keypad application mode 173
Keypad numeric mode 173
Line transmit mode 138
Numeric keypad mode 174
National replacement character set mode 70
Origin mode 108
Page cursor coupling mode 166
Printer extent mode 181
Print form feed mode 181
Protected fields attribute 129
Restore cursor 229
Report displayed extent 230
Report mode 221
Report selection or setting 227
Request displayed extent 230
Request mode 218
Request presentation report 210
Request selection or setting 226
Request terminal state report 206
Requesting the user-preferred supplemental set 231
Restore presentation state 216
Restore terminal state 208
Select active status display 189
Save cursor 229
Select character protection attribute 127
Space compression mode 147
Selecting an operating level 67
Scrolling mode 187
Screen mode 187
Set columns per page — recommended 106
Selective erase in display 124
Selective erase in line 125
Set lines per page 107
Select status line type 189
310 Control Function Index
DECSTBM . . Set top and bottom margins 108
DECSTR . . . Soft terminal reset 242
DECSWL . . . Single-width line 116
DECTABSR. . Tab stop report 216
DECTCEM . . Text cursor enable mode 161
DECTEM . . . Transmit execution mode 148
DECTLTC. . . Transmit line termination characters 146
DECTSR . . . Terminal state report 207
DECTTC . . . Set transmit termination character 144
DECUDK . . . User-defined keys 175
DECVCCM . . Vertical cursor coupling mode 165
DECXMIT. . . Transmit 149
DECXCPR . . Extended cursor position report 202
DECXRLM . . Transmit rate limiting mode 273
DL Delete line 120
DSR Device status reports 201
cursor position report (CPR) 202
extended cursor position report (DECXCPR) 202
keyboard dialect 203
locator device port 204
printer port 202
user-defined keys 203
VT3 00 operating status 201
— E—
— Enable session 256
ECH Erase character 124
ED Erase in display 122
EL Erase in line 123
EPA End protected area 128
ERM Erasure mode 119
ESA End selected area 143
-G-
GATM Guarded area transfer mode 141
— H—
HVP Horizontal and vertical position (See CUP.) 162
Control Function Index 311
—I—
ICH Insert character 122
IL Insert line 121
IRM Insert/replace mode 119
— K—
KAM Keyboard action mode 170
— L—
LNM Line feed/ new line mode 171
LSO Locking shift GO 78
LSI Locking shift Gl 78
LS1R Locking shift Gl, right 78
LS2 Locking shift G2 78
LS2R Locking shift G2, right 78
LS3 Locking shift G3 78
LS3R Locking shift G3, right 78
— M—
MATM Multiple area transfer mode 143
MC Media copy 182
assign printer to active session 185
autoprint mode 183
print all pages 184
print composed main display 184
printer controller mode 183
print cursor line 184
print page 183
release printer 185
start printer-to-host session 184
stop printer-to-host session 184
Mapping character sets 76
— N—
NP Next page 109
312 Control Function Index
— p—
PP Preceding page 109
PPA Page position absolute 110
PPB Page position backward 110
PPR Page position relative Ill
— R—
RIS Hard terminal reset 244
RM Reset mode (for ANSI and DEC private modes) 224
— s—
S7C1T Sending 7-bit CI controls 69
S8C1T Sending 8-bit CI controls 69
SATM Selected area transfer mode 142
SCS Designating character sets 73
SD Pan up (scroll down) 163
SGR Select graphic rendition (visual attributes) 115
SL Pan right (scroll left) 164
SM Set mode (for ANSI and DEC private modes) 223
SPA Start protected area 128
SR Pan left (scroll right) 164
SRM Send/receive mode (local echo) 186
SS2 Single shift G2 79
SS3 Single shift G3 79
SSA Start selected area 143
STS Set transmit state 148
SU Pan down (scroll up) 163
— T—
TBC Tab clear 245
TTM Transmit termination mode 139
Visual attribute protection (VT131 style).. See DECPRO.
VTlOOmode 66
VT300mode 66
Control Function Index 313
BY FUNCTION
ANSI Conformance Levels
Announcing ANSI conformance levels 80
Character Attributes
See Visual Character and Line Attributes.
Character Protection
Independent
End protected area (EPA) 128
Select character protection attribute (DECSCA) 127
Start protected area (SPA) 128
Visual Attribute (VT131 Style)
Protected fields attribute (DECPRO) 129
Character Sets
Assign user-preferred supplemental set (DECAUPSS) 80
Clearing soft sets (DECDLD) 101
Designating character sets (SCS sequences) 73
Down-line-loading soft characters (DECDLD) 90
Locking shifts
locking shift GO (LSO) 78
locking shift Gl (LSI) 78
locking shift Gl, right (LS1R) 78
locking shift G2 (LS2) 78
locking shift G2, right (LS2R) 78
locking shift G3 (LS3) 78
locking shift G3, right (LS3R) 78
Mapping character sets 76
National replacement character set mode (DECNRCM) 70
Single shifts
single shift G2 (SS2) 79
single shift G3 (SS3) 79
314 Control Function Index
Communication
Transmit rate limiting mode (DECXRLM) 273
Control Characters
Sending 7-bit CI controls (S7C1T) 69
Sending 8-bit CI controls (S8C1T) 69
Cursor Movement and Panning
Cursor backward (CUB) 162
Cursor down (CUD) 163
Cursor forward (CUF) 162
Cursor position (CUP) 162
Cursor up (CUU) 162
Horizontal and vertical position (HVP) 162
Horizontal cursor coupling mode (DECHCCM) 165
Page cursor coupling mode (DECPCCM) 166
Pan down (scroll up, SU) 163
Pan left (scroll right, SR) 164
Pan right (scroll left, SL) 164
Pan up (scroll down, SD) 163
Text cursor enable mode (DECTCEM) 161
Vertical cursor coupling mode (DECVCCM) 165
Display
Insert/replace mode (IRM) 119
Send/receive mode (SRM) I 86
Screen mode (DECSCNM) 187
Scrolling mode (DECSCLM) I8 7
Select active status display (DECSASD) 189
Select status line type (DECSSDT) 189
Editing
Delete character (DCH) 121
Delete line (DL) 12°
Erase character (ECH) 124
Erase in display (ED) 122
Erase in line (EL) I 23
Erasure mode (ERM) H 9
Control Function Index 315
Insert character (ICH) 122
Insert line (IL) 121
Insert/replace mode (I RM) 119
Selective erase in display (DECSED) 124
Selective erase in line (DECSEL) 125
Keyboard
Autorepeat mode (DECARM) 172
AutOwrap mode (DECAWM) 172
Backarrow key mode (DECBKM) 170
Cursor keys mode (DECCKM) 173
Keyboard action mode (KAM) 1 70
Keypad application mode (DECKP AM) 173
Keypad numeric mode (DECKPNM) 173
Keyboard usage mode (DECKBUM) 175
Line feed/ new line mode (LNM) 171
Numeric keypad mode (DECNKM) 174
User-defined keys (DECUDK) 175
Local Editing
Edit key execution mode (DECEKEM) 136
Edit mode (DECEDM) 136
End selected area (ESA) 143
Guarded area transfer mode (GATM) 141
Line transmit mode (DECLTM) 138
Multiple area transfer mode (MATM) 143
Selected area transfer mode (SATM) 142
Set transmit state (STS) 148
Set transmit termination character (DECTTC) 144
Space compression mode (DECSCFDM) 147
Start selected area (SSA) 143
Transmit execution mode (DECTEM) 148
Transmit line termination characters (DECTLTC) 146
Transmit (DECXMIT) 149
Transmit termination mode (TTM) 139
VT131 transmit mode (DEC131TM) 140
Operating Level
VT52 mode IDECANM, ANSI mode off) 257
VT100 mode (DECSCL) 66
VT300 mode (DECSCL) 66
316 Control Function Index
Page Memory
Column mode <DECCOLM| — not recommended 106
Next page <NP> 109
Origin mode (DECOM) 108
Page position absolute (PPA) HO
Page position backward (PPB) 110
Page position relative (PPR) 111
Preceding page (PP) 109
Set columns per page (DECSCPP) — recommended 106
Set lines per page (DECSLPP) 107
Set top and bottom margins (DECSTBM) 108
Panning
See Cursor Movement and Panning.
Printing
Media copy (MC) functions
assign printer to active session 1°5
autoprint mode 183
print all pages I 84
print composed main display I 84
print cursor line 1° 4
printer controller mode I 88
print page i0 °
release printer l 8 ^
start printer-to-host session i84
stop printer-to-host session I 84
Printer extent mode (DECPEX) l g l
Print form feed mode (DECPFF) 181
NOTE: See Volume 2, Chapter 16 for the following graphics printing functions.
graphics expanded print mode (DECGEPM) Vol. 2
graphics print background mode (DECGPBM) Vol. 2
graphics print color mode (DECGPCM) Vol.2
graphics print color syntax (DECGPCS) Vol. 2
graphics rotated print mode (DECGRPM) Vol. 2
graphics to host Vol. 2
graphics to printer Vol. 2
Control Function Index 317
Reports
Control function settings 225
report selection or setting (DECRPSS) 227
request selection or setting (DECRQSS) 226
Device attributes (DA) 196
primary DA 197
secondary DA 199
Device status reports (DSR) 201
cursor position report (CPR) 202
extended cursor position report (DECXCPR) 202
keyboard dialect 203
locator device port 204
printer port 202
user-defined keys 203
VT300 operating status 201
Mode settings 218
report mode (DECRPM) 221
request mode (DECRQM) 218
reset mode (RM) 224
set mode (SM) 223
Presentation state reports 209
cursor information report (DECCIR) 210
request presentation report (DECRQPSR) 210
restore presentation state (DECRSPS) 216
tab stop report (DECTABSR) 216
Terminal identification (DECID) 200
Terminal state reports 205
color table report (DECCTR) 207
request terminal state report (DECRQTSR) 206
restore terminal state (DECRSTS) 208
terminal state report (DECTSR) 207
User-preferred supplemental set 231
reporting the supplemental set (DECAUPSS) 231
requesting the supplemental set (DECRQUPSS) 231
Window reports 230
report displayed extent (DECRPDE) 230
request displayed extent (DECRQDE) 230
Resetting the Terminal
Hard terminal reset (RIS) 244
Reset mode (RM) (for ANSI and DEC private modes) 224
318 Control Function Index
Set mode (SMI (for ANSI and DEC private modes) 223
Soft terminal reset (DECSTR) 242
Tabulation clear (TBC) 245
Saving and Restoring the Cursor State
Restore cursor (DECRC) 229
Save cursor (DECSC) 229
Session Management
Enable session 256
Visual Character and Line Attributes
Double-width, double-height line (DECDHL) 116
Double-width, single-height line (DECDWL) 116
Select graphic rendition (SGR) 115
Single-width line (DECSWL) 116
Control Function Index 319
Index
7-bit ASCII code table, 16 to 18
7-bit CI controls (S7C1T), 69
7-bit code extension technique, 39
7-bit codes, 15
7-bit CO control characters, 28 to 30
sending from the keyboard, 55, 57
(Table 3-5)
7-bit and 8-bit environments, 40 to
41
conventions for received codes. 40
conventions for transmitted codes.
41
8-bit codes, 15
8-bit CI controls (S8C1T), 69
8-bit code table, 18 to 20
CO (control zero) and CI (control
one) characters, 18
GL (graphic left) and GR (graphic
right) characters, 20
keyboard codes based on, 49
used in 7-bit or 8-bit environment,
40
8-bit CI control characters, 31 to 32
cannot send from keyboard, 55
American National Standards
Institute (ANSI), 4, 13
ANSI mnemonics, 18
ANSI sequences, 34
ANSI conformance levels, 80 to 81
ANSI modes
setting and resetting, 223 to 225,
220 (Table 12-2)
requesting and reporting, 218 to
223, 220 (Table 12-2)
ANSI partial page, 137
Arrow keys, 51
codes, 52 (Table 3-2)
selecting their function, 173
ASCII code table, 16 to 18
control characters, 18
graphic characters, 16
Autoprint mode. 183
Autorepeating keys, 60
turning on and off, 60, 172
Autorepeat speed, 60
Autowrapping text, 172 to 173
Auxiliary keypad. See Numeric
keypad
-A-
-B-
Active position in page memory, 161 Backspace (BS) character, 50
Index 321
Baud rate, 9
for autorepeating keys, 60
for modems, 269, 271, 272, 278
for non-Digital systems, 264 to
265
transmit rate limiting, 273
Binary digits, 13
Bitmap, 8
Blinking characters, 115
Block editing, 6. See also Local
editing
Bold characters, 115
not available for control charac-
ters, 116
Built-in character sets, 9, 71 to 72
(Table 5-1)
Break key, 55, 61, 172, 175 ,
break function, 279
CO and CI control characters, 18,
20, 28 to 33
converting CI codes to 7-bit code
extensions, 41
sending CI controls to the host,
68 to 69
using Cl controls in escape se-
quences, 39
Character attributes. See Visual char-
acter attributes
Character cell, 7
for soft character sets, 82 to 83
Character encoding, 12 to 44
Character format, 260
Character positions in a code table,
16
Character protection, 125 to 130
independent style, 126 to 128
reporting on the cursor position,
212 to 213
sequence summary, 134 (Table 8-4)
visual attribute (VT131) style, 129
to 130
Characters and character sets, 15
Character sets, 9, 20 to 28
7-bit, 17
8-bit, 19
available. 73 (Table 5-1)
DEC Multinational, 20, 21 to 22
DEC Special Graphic, 26
DEC Supplemental Graphic, 21 to
22
DEC Technical, 27
display controls font, 42 to 43
down-line-loadable (soft), 28, 82 to
101
ISO Latin Alphabet Nr 1 supple-
mental graphic, 23
letters with accents and diacritical
marks, 21. 23
local editing, 153
national replacement character
(NRC) sets, 24 to 25, 70
report on active sets, 215. 231
soft, 28, 81 to 101
special symbols, 21, 23, 26
VT100 line-drawing, 26
VT200 and VT300 modes only, 23,
27, 28
Character sets, selecting, 72 to 101
ANSI conformance levels, 80 to 81
assigning the preferred supplemen-
tal set, 80
designating, 73 to 75 (Table 5-2)
designating soft sets, 97 to 98
mapping, 76 to 79
national replacement character
sets, 70, 79
preferred supplemental character
sets, 80
soft character sets, 82 to 101
VT100 mode, 76 (Figure 5-2)
322 Index
VT300 mode, 77 (Figure 5-3)
Character size, 7
Clr Field key, 58
CLR PAGE key, 58
Code table, 15
7-bit ASCII code table, 16 to 18
8-bit code table, 18 to 20
Coding conventions, 40 to 41
Coding standards, 13 to 14
Color table report, 207
Color printing. See Volume 2 of this
manual
Communication, 259 to 280
break function, 279
character format, 260
connecting to Digital devices, 260
to 263
connecting to non-Digital devices,
264 to 265
data flow, 273
features, 9
modems, 271 to 272, 275 to 279
ports, 265 to 270
set-up screen. 274
standards and certification, 280
Communication features, 9
Communication lines for sessions, 5,
251, 252
Compose Character key, 50
Compose sequences, 48, 50. See also
Installing and Using the VT300
Series Video Terminal, Chapter
6
Connectors, 9, 265
Control characters, 15, 18, 28 to 33
control (CO) 7-bit characters, 28
to 30 (Table 2-2)
control 1 (CI) 8-bit characters, 31
to 32 (Table 2-3)
7-bit equivalents for 8-bit charac-
ters, 32 to 33 (Table 2-4)
in 7-bit or 8-bit environment, 40 to
41
in escape sequences, 39
sending 7-bit or 8-bit Cl controls
to the host, 70
Control functions, 34 to 40. See also
the Control Functionlndex
7-bit code extension technique, 39
control characters in, 39
control sequences, 36
device control strings, 37
escape sequences. 35
factory-default settings, 242 to
243 (Table 13-1)
sequence format, 35
sent to the host, 47
Control function settings, 225 to 229
reporting, 227 to 229
requesting. 226 to 227
Converting binary code to an ASCII
character, 87 to 88
Coupled cursor, 164
CR (carriage return) character
Return key, 50
in printing, 182
CSI control character, 36
Ctrl key. 50, 172
Cursor, 161 to 163
characters, 161
home position, 108
visible or invisible, 161
moving on the current page, 161
to 163
sequence summary, 167 to 168
Cursor control
arrow keys, 51, 52 (Table 3-2)
Cursor coupling modes, 164 to 167
horizontal, 165
vertical. 165 to 166
page, 166 to 167
Cursor information report, 210 to
Index 323
216
Cursor movement
on the current page, 161 to 163
panning with the cursor, 164 to
167
sequence summary, 167 to 168
Cursor position report, 202
extended position report, 202
Cursor state, 224 to 230
restoring, 224 to 230
saving, 229
-D-
Data flow, 273
Data processing keys, 49
selecting, 174 to 175
Data terminal ready (DTR) signal,
202, 203, 266, 267
DCS control character, 37
Debugging control codes in applica-
tions, 41
DEC Multinational character set, 20,
21 to 22, 72
DEC private mode settings, 218 to
225
reporting, 220 to 221 (Table 12-31,
221 to 223
requesting, 218 to 221
setting and resetting, 223 to 225,
220 to 221 (Table 12-3)
DEC Special Graphic character set,
26
DEC Supplemental Graphic charac-
ter set, 21 to 22
assigning as the preferred supple-
mental set, 81. See also DEC
multinational character set
DEC Technical character set, 27
DEL (delete! character, 18, 50
Delete Character key, 59
Delete <x] key function, 170 to 171
Delete Line key, 59
Deleting
a character, 121 to 122
a line, 120 to 121
Design and load a soft character set,
82 to 98
Designating character sets
hard sets, 73 to 75 (Table 5-2)
soft sets, 97 to 98
Device attributes, 196 to 205
alias responses, 199
primary DA, 197 to 199
secondary DA, 199 to 201
Device control strings, 37
Device status reports, 201 to 205
cursor position, 202
extended cursor position, 202
keyboard dialect, 203
locator device port, 204
printer port, 202
user-defined keys. 203
VT300 operating status, 201
Digital devices
connecting to, 260 to 263
Digital's private control functions,
1-9. See also DEC private
modes
Display area, 7
Displaying control characters on the
screen, 16, 41 to 42
Display controls mode, 41
Control Representation feature in
set-up, 41
display controls font, 42 to 43
Display features, 7 to 8
Displaying pages from page memory.
See Moving to another page
Display Set-Up screen
to select cursor character, 161
Do key
as a user-defined key, 175
324 Index
Double-width, double-height line. 116
Double-width line, single-height line,
116
Down-line-loadable (soft) character
set, 28, 82 to 101. See also Soft
character sets
device control strings, 37
Dual sessions, 5, 249. See also Page
memory and Session
management
session resources, 252 to 254
independent resources, 252 to 253
shared resources, 253 to 254
two ways to manage sessions, 250
to 252
Dynamically redefinable character set
(DRCS). See soft character sets
DRCS buffer, 93
-E-
EDIT key, 59
Editing
deleting a character, 121 to 122
deleting a line, 120 to 121
erasing a character, 124
erasing a line, 123, 125
erasing protected characters. 119
erasing the display, 122 to 123,
124 to 125
inserting a character, 122
inserting a line, 121
inserting or replacing data, 119 to
120
sequence summary, 131 to 133
Editing key codes, 51 (Table 3-1)
Editing keypad, 51
Emulating VT series terminals, 65 to
70
level 1 (VT100 mode), 66
level 3 (VT300 mode), 66
reporting on the operating level,
197
selecting an operating level, 68
Enter key
sending the same character(s) as
the Return key, 172
Environments, 7-bit or 8-bit, 40 to
41
VT52 or VT100 mode (7-bit), 40
VT300 mode (8-bit), 40 to 41
Erasing
a character, 124
a line, 123, 125
protected characters, 119
the display, 122 to 123, 124 to
125
Erasure mode. See also Erasing
effect on character protection, 126,
127
ESC character, 35
Escape sequences, 35
European languages. See National re-
placement character sets
FF (form feed) character, 171, 183
in display controls mode, 44
Function keys (Fl through F20), 50,
55. See also User-Defined keys
codes, 55 to 56 (Table 3-4)
predefined keys, 55
-G-
G0 through G3 logical character
sets, 72
reporting on, 207, 213 to 216
General features, 7 to 9
Graphics left (GL) and graphics right
(GR) logical tables, 20
for display controls font, 41 to 42
mapping designated sets to, 72
reporting on, 207, 213 to 216
Index 325
GL characters in a 7-bit or 8-bit envi-
ronment, 49
GR characters in an 8-bit environ-
ment, 49
Graphic characters
definition, 15
Graphics tablet
reporting on the locator device
port, 204
-H-
Hard character sets, 71 to 72 (Table
5-1)
Hard terminal reset (RIS), 61, 244
actions, 244
caution against using, 244
effect on user-defined keys. 176
Help key
as a user-defined-key, 175
HLS (hue/lightness/saturation) color
coordinate system
reporting on, 206, 208
Hold Session key. 55, 61. 172, 175
Home Cursor key, 58
Home cursor position, 108
Host system
and dual sessions, 5, 249
Host-writable status line, 189
HT (tab) character, 50
-I-
Independent character protection,
126 to 128
different from visual attribute
(VT131 style) protection, 126
to 127
effect of erasure mode, 127
Insert/Overstrike key, 58
Inserting
a character, 122
a line, 121
inserting or replacing data, 119 to
120
Inserting spaces. See Inserting
characters
International Organization for
Standardization (ISO), 13
ordering standards, 14
In-use table, 20
Invisible characters, 115
ISO Latin alphabet number 1 supple-
mental set, 23
as part of ISO Latin-1 character
set, 23
selecting as the user-preferred sup-
plemental set, 80
-J-
Jump scrolling, 188
-K-
Keyboard codes, 47 to 61
7-bit control codes, 55, 57 (Table
3-5)
editing keypad, 51 to 52
local editing mode, 58 to 59 (Table
3-6)
main keypad, 48 to 50
standard keys, 48 to 49
function keys, 50
numeric keypad, 52, 53 to 54
(Table 3-3)
top-row function keys, 55, 55 to
56 (Table 3-4)
turning autorepeat on and off, 60
unlocking the keyboard, 61
Keyboard control functions, 170 to
175
locking and unlocking the key-
board. 170
selecting the <x] key function,
170 to 171
326 Index
selecting the characters sent by
the Return key, 171
selecting the function of line feeds,
form feeds and vertical tabs,
171
turning the autorepeat feature on
or off, 172
selecting the function of the arrow
keys, 173
numeric keypad, 173 to 174
selecting typewriter or data pro-
cessing keys, 174 to 175
sequence summary, 191 to 194
Keyboard dialect report, 203
Keyboard Set-Up screen
selecting typewriter or data pro-
cessing keys, 49
selecting numeric keypad codes,
52
selecting the autorepeat function
for keys, 60
Keys that do not repeat. 60
-L-
Light or dark screen, 187
Line attributes, 8
setting, 116
Line feed/new line mode (LNM), 171
to 172
effect on Return key, 50, 171
LF (line feed) character
in display controls mode, 44
and the Return key, 50, 171
and printing, 183
Local echo, 186 to 187
Local editing, 6, 134 to 158
7-bit environment, 154 to 155
8-bit environment, 153 to 154
character sets, 153
control functions used, 135
defining the size of the character
block. 137 to 141
description, 135
end-of-block characters, 144 to 146
end-of-line characters, 146 to 147
examples, 149 to 153
keys, 58 to 59 (Table 3-6)
selected areas, 142 to 144
selecting edit mode, 136
selecting the characters to send,
141 to 144
selecting when to switch modes,
136 to 137
sending edited data to the host,
148 to 149
space compression, 147
sequence summary, 156 to 158
used with visual attribute charac-
ter protection, 129
Locator device port report, 204
Lock key, 50, 172
Locked keyboard. See also Unlocking
the keyboard
keys that still work, 61
Locking shifts, 78
-M-
Main keypad codes, 48 to 50
standard keys, 48 to 49
function keys, 50
Managing dual sessions, 5, 250
Mapping a character set, 76 to 79
locking shifts, 76, 78
single shifts, 76, 79
Modems, 271 to 272, 275 to 279
Monitor size, 7
Mouse
reporting on, 204 to 205
Moving to another page, 109 to 111
summary, 113
with cursor and panning functions,
166
Multiple-page display memory, 6
Multiple system communications
Index 327
(MSC), 250 to 252
-N-
National keyboards
differences. See Chapter 3
National replacement character set
mode, 70
National replacement character sets
(NRCs), 24
characters that vary from the
ASCII set, 25
selecting, 70
Negative image characters, 115
Next Page key, 59
Non-Digital devices
connecting to, 264 to 265
Nonvolatile RAM (NVR), 82, 241,
244
Numeric keypad
codes, 52, 53 to 54 (Table 3-3)
sending numeric characters or con-
trol functions, 173 to 174
Numeric parameters, 36
-O-
Operating levels
character sets available, 72 (Table
5-1)
common features, 66
control functions ignored, 67
(Table 4-1)
level 1 (VT100 mode), 66
level 3 (VT300 mode), 66
reporting on, 196, 197
selecting, 68
Operating modes
on-line, 10
local, 10
Operating states
reporting on, 205
VT300 mode, 7-bit controls, 10
VT300 mode, 8-bit controls, 10
VT100 mode, 11
VT52 mode, 11
Operating status, 201
-P-
Page. 6
compared to display, 161
sending partial pages in local edit-
ing, 137
Page format, 106 to 109
selecting 80 or 132 columns per
page, 106
sequence summary, 112 to 113
setting lines per page, 107
setting the page origin, 108
setting top and bottom margins,
108
Page memory, 6, 102 to 113
description, 103
for a single session, 104
for dual sessions, 105
margins. 103
moving to another page, 109 to
111
sequence summary, 112 to 113
Page sizes
default, 103
single session, 104
dual sessions, 105
Panning. 163 to 167
direction. 163 to 164
with the cursor, 164 to 167
sequence summary, 167 to 168
Parameters
numeric, 36
selective, 37
PF1 through PF4 keys, 174
Pixels, 82
Ports, 265 to 270
Power-up
328 Index
clearing user-defined keys, 176
Predefined function keys, 55
Presentation state reports, 209 to
218
cursor information report, 210 to
216
requesting, 210
restoring, 217 to 218
tab stop report, 216
Prev Page key, 59
Primary DA report. 197
Printer port control functions, 181 to
182
selecting how much data to print,
181
sending a form feed, 181 to 182
Printer port report, 202
Printing control functions, 182 to
185
assigning the printer to the active
host session, 185
printing a display line: autoprint
mode, 183
printing all pages, 184
printing a page, 183
printing the cursor line, 184
printing the screen, 184
releasing the printer, 185
sending characters directly to the
printer: printer controller
mode, 183
starting and stopping the printer-
to-host session. 184
sequence summary, 191 to 194
Printing visual attributes, 185 to 186
sending line attributes. 185
sending visual character attributes,
186
Private sequences, 34
Protected and unprotected areas, 127
to 128
Reports, 195 to 240
ANSI and DEC private mode set-
tings, 218 to 225
control function settings, 225 to
229
cursor state, 229 to 230
device attributes, 196 to 200
device status reports, 201 to 205
presentation state, 209 to 217
sequence summary, 233 to 240
terminal identification, 200
terminal state reports, 205 to 209
user-preferred supplemental set,
231 to 232
windows, 230 to 231
Releasing the printer, 185
Resetting the terminal, 241 to 248
hard terminal reset, 244 to 245
sequence summary, 246
soft terminal reset, 242 to 243
tab clear, 245
Return key, 50, 171
Reverse characters. See Negative-
image characters
ROM cartridge firmware, 7
Screen display control functions, 186
to 190
local echo, 186 to 187
light or dark screen, 187
scrolling mode, 187 to 188
selecting the indicator or host sta-
tus line. 188 to 190
sequence summary, 194
Scrolling
speed, 187 to 188
versus panning, 160
Scrolling region (local editing), 138
Secondary DA report, 199 to 200
Index 329
Select character set (SCS) sequences,
73 to 75 (Table 5-2)
Select graphic rendition (SGR). See
Visual character and line
attributes
Selected areas in local editing, 142
to 144
Selecting a character set, 72 to 81
in VT100 mode. 76
in VT330 mode. 77
Selecting a page size. See Page
format
Selecting a status line, 188 to 190
Selective parameters, 37
Session management, 249 to 256
dual sessions, 249 to 250
multiple system communications
(MSC), 254
session resources, 252 to 254
SSU, 254 to 255
Session Support Utility, 254 to 255
SSU environment, 254 to 255
using SSU, 255
Session Switch key, 55. 172, 175
Setting line attributes. 116 to 117
single-width, single-height line.
116
double-width, single-height line.
116
double-width, double-height line,
116 to 117
Setting visual character attributes.
114 to 117
Set-up, 7
Set-Up key, 55, 175
Shift key, 50, 172
for user-defined keys, 175
Single shifts, 79
Single-width, single-height line. 116
Sixels, 84
Soft character sets. 28, 71, 82 to
101
clearing, 101
coding, 84 to 89
converting binary code to an
ASCII character, 87 to 88
(Table 5-5)
designating, 97 to 98
designing, 82 to 83
down-line-loading, 90 to 96
example, 98 to 100
SP (space) character, 18, 182
Status line, 187 to 190
Supplemental character sets, See
Character sets
-T-
Tab key. 50
Tab stops
converted to spaces when printing
current page, 182
reporting on, 216
Terminal identification, 200
Terminal state reports, 205 to 209
reporting the color table, 207 to
208
reporting the terminal state, 207
requesting, 206
restoring, 208 to 209
Text features, 8
Top-row function key codes, 55 to 56
(Table 3-4)
Transmit key, 59
Transmit Rate Limiting set-up fea-
ture, 60
Typewriter or data processing keys,
49, 174 to 175
-U-
Underlined characters, 115
Unlocking the keyboard, 61, 170
User-defined keys (UDKs), 175 to
181
330 Index
locking and unlocking, 178
notes on loading UDKs, 179 to
180
programming UDKs. 176 to 181
summary, 192
UDK memory space, 176
using UDKs, 176
User-defined keys report, 203
User-preferred character sets. See
Character sets
User-preferred supplemental set re-
ports, 231 to 232
reporting, 232
requesting, 231
User windows, 5
Visual attribute protection, 129 to
130
Visual character and line attributes,
114 to 117
reporting on the writing rendition,
211 to 212
setting visual character attributes,
114 to 117
setting line attributes, 116 to 117
sequence summary, 117
VT (vertical tab) character, 171, 182
in display controls mode, 44
VT52 mode, 257 to 258
7-bit environment only. 40
control codes, 258
entering, 257
exiting, 258
VT100 line-drawing character set, 26
VT100 mode, 11
7-bit environment only, 40
limits. 66 to 67
selecting, 68
selecting character sets, 76
VT131-style block editing. See Local
editing
VT131-style character protection. See
Visual attribute protection
VT131 partial page, 137
VT200 series terminals
using VT200 settings. See VT300
mode
VT300 features, 3 to 11
VT300 mode, 10
no limits. 66
selecting, 68
selecting character sets, 77
VT300 series terminals, 3 to 4
compared to other VT series ter-
minals, 281 to 284
-W-
Wait indicator. 61, 170
Windows
cursor movement and panning,
163 to 167
reporting, 230
requesting, 230
user windows, 5
Wrapping text automatically, 172 to
173
■X-
<x] (delete) key, 50
as a backspace key, 170 to 171
XON/XOFF signals. See
Communication
in display controls mode, 44
Index 331
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