Digital Equipment VT520 Operating instructions

VT520/VT525VideoTerminal
ProgrammerInformation
dt
Order Number: EK-VT520-RM. A01

July 1994
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Copyright © Digital Equipment Corporation 1994. All Rights Reserved.
Printed in U.S.A.
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This document was prepared using VAX DOCUMENT Version 2.1.

Preface
Introduction
This manual provides detailed information for advanced users, consultants, and
programmers. This manual has the following parts, chapters, and appendices:
• Part I, VT520 Video Terminal
• Chapter 1, Overview
• Chapter 2, Set-Up
• Chapter 3, Desktop Features
• Part II, VT520 ANSI Mode
• Chapter 4, ANSI Control Functions Summary
• Chapter 5, ANSI Control Functions
• Chapter 6, SCO Console Emulation
• Chapter 7, Character Sets
• Chapter 8, Keyboard Processing
• Chapter 9, Communications
• Chapter 10, Printer Port
• Part III, VT520 ASCII Emulation
• Chapter 11, ASCII Emulations and Control Functions
• Chapter 12, ASCII Escape Sequences
• Chapter 13, Defining and Loading ASCII Character Fonts
• Appendix A, VT Keyboard Legend Data
• Appendix B, Enhanced PC Keyboards
• Appendix C, ASCII Keycodes and Local Functions
• Appendix D, VT520 Termcap Data
• Appendix E, ANSI Control Function Index
iii

Conventions
The following conventions are used in this manual:
Set-Up features Terminal Set-Up menu selections appear in boldface type.
Alt/Ctrl/Print Screen Multiple keys are separated by a slash (/) and should be
pressed in combination. That is, all three keys Alt,Ctrl, and
Print Screen are pressed down at the same time.
Characters in control
functions Control function characters are in boldface type. Below each character is a column/row number that indicates the
character’s position in a standard code table. For example:
ESC # 6
( = Control function
1/11 2/3 3/6
( = Column/row numbers
Parameters Parameters appear in italic type.
Note Provides general information.
How to Use This Manual
The VT520 Video Terminal Programmer Information is written for four audiences:
an advanced user, who needs to know more about the terminal Set-Up features;
a programmer, who develops application programs; a software product support
person, who provides assistance to application programmers and users; and a
hardware systems engineer, who need more information on terminal connections.
Advanced User
If you have read the VT520 Video Terminal Installation and Operating
Information manual and need more information on the the terminal Set-Up
features, you may wish to refer to the following:
•Index
•Chapter 1—Overview—Provides a brief summary of the product.
•Chapter 2—Set-Up—Describes each entry in the Set-Up menus in the order
that is displayed in the terminal.
•Chapter 3—Desktop Features—Provides a more in-depth description of the
desktop features of the terminal.
•Chapter 6—Keyboard Processing—Describes the differences in the types
of keyboard layouts supported, local functions, and accessibility aids.
Programmer
If you are using ANSI control functions for your program, then you may wish to
start with Part II of the manual:
•Chapter 4—ANSI Control Function Summary— Provides a tutorial
section on Control Functions and information on designing and down-line
loading a Soft Character set (soft font). In this chapter, the Control Functions
are grouped according to the task to be performed. The information on each
Control Function is very brief. If you need more information, the mnemonic
at the end of the line item refers to a command section in Chapter 5.
•Chapter 5—ANSI Control Functions—Provides in-depth information on
each control function listed in alphabetic order according to the mnemonic.
•Chapter 2—Set-Up—Lists the Set-Up factory defaults at the end of this
chapter, with their host control code mnemonic.
iv

•Chapter 6—Keyboard Processing—Describes the keyboard layouts,
keyboard-to-host interface, keypad sequences, local functions, LEDs controls,
languages, accents, scan codes, and control codes.
•Chapter 9—Communications—Describes the serial communications from
the terminal to the host ports and the hardware and software handshaking.
•Chapter 10—Printer Port—Describes the parallel printer port and the
switching sequences for the modes supported.
•Appendix A—VT Keyboard Legend Data
•Appendix B—Enhanced PC Keyboard Legend Data
•Appendix D—VT500 Termcap Data
If you are developing a application program for a SCO Console, then you may
wish to refer to:
•Chapter 6—SCO Console Emulation—Describes the SCO Console mode,
including the Control Functions relative to the SCO Console applications.
If you are using ASCII control functions for your program, then you may wish to
start with Part III of the manual:
•Chapter 11—ASCII Emulations and Control Functions— Provides an
overview of the ASCII emulation, the coding notation, and the symbols used
in the ASCII sequence tables.
•Chapter 12—ASCII Escape Sequences—Summarizes the ASCII escape
and control sequences for the various ASCII emulation modes, according to
the task to be performed.
•Chapter 13—Defining and Loading ASCII Character Fonts – Provides
specific information on loading font banks and designing an ASCII character
font.
•Appendix C—ASCII Keycodes and Local Functions
Software Product Support
If you are helping a user or programmer with an application, then you may wish
to refer to the following:
•Appendix E—ANSI Control Function Index—Lists the control functions
by their final character, which makes them easier to find in a program. The
mnemonic at the end of the line item refers to a command in Chapter 5, listed
in alphabetic order.
•Index—Lists control functions by mnemonic or by name and lists other
subjects by topic.
•Chapter 5—ANSI Control Functions—Provides in-depth information on
specific control functions.
•Chapter 6—Keyboard Processing—Lists the scan codes Make and Break
sequences.
•Appendix D—VT500 Termcap Data—Provides the Termcap information for
ANSI emulations.
v

Hardware Systems Engineer
If you are helping a user to install the terminal or to operate within a specific
environment, then you may wish to refer to the following:
•Index—Search by topic.
•Chapter 1—Overview Provides a brief summary of the product.
•Chapter 2—Set-Up Describes each entry in the order that is displayed in
the terminal, starting with the Actions menu and lists the modes supported.
Also lists the Set-Up factory defaults.
•Chapter 9—Communications—Describes the serial communications from
the terminal to the host ports, pin numbers and signals, and the hardware
and software handshaking.
•Chapter 10—Printer Port—Describes the parallel printer port, pin numbers
and signals, and modes supported.
vi

Contents
Preface ............................................................ iii
Part I VT520 Video Terminal
1 Overview
1.1 Introduction................................................ 1–1
1.2 CommunicationsFeatures..................................... 1–1
1.3 KeyboardFeatures........................................... 1–2
1.4 PrinterPortFeatures......................................... 1–3
1.5 Display and Text Capabilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–3
1.5.1 ANSI .................................................. 1–3
1.5.2 ASCII.................................................. 1–3
1.6 EnhancedSet-Up............................................ 1–4
1.7 Desktop Productivity Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–4
1.8 CharacterSetSupport........................................ 1–4
1.9 Ergonomics (Human Factors) Features . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–4
1.10 Field-UpgradableFirmware.................................... 1–5
1.11 Comparison with previous VT Terminals . . . . . . . . . . . . . . . . . . . . . . . . . . 1–6
2 Set-Up
2.1 EnteringSet-Up............................................. 2–1
2.1.1 EffectsofEnteringSet-Up.................................. 2–2
2.1.2 Set-UpLanguages ........................................ 2–2
2.1.3 Power-On Settings and Defaults . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–2
2.1.4 Self-testErrorMessages ................................... 2–3
2.1.5 ContextSensitivity........................................ 2–3
2.1.6 Set-UpSummaryLine..................................... 2–5
2.1.7 Set-UpStatusMessages.................................... 2–5
2.1.8 StatusLine ............................................. 2–6
2.1.9 KeyboardIndicatorLine ................................... 2–6
2.2 Set-UpScreenText .......................................... 2–7
2.3 MainMenu ................................................ 2–8
2.3.1 On-Line ................................................ 2–8
2.3.2 SaveSettings............................................ 2–9
2.3.3 RestoreSettings.......................................... 2–9
2.3.4 ExitSet-Up ............................................. 2–9
2.4 ActionsMenu............................................... 2–9
2.4.1 ClearDisplay............................................ 2–9
2.4.2 ClearCommunications..................................... 2–9
2.4.3 ResetthisSession ........................................ 2–10
2.4.4 RestoreFactoryDefaults................................... 2–10
2.4.5 Clock, Calculator, Show Character Sets . . . . . . . . . . . . . . . . . . . . . . . . 2–11
vii

2.4.6 BannerMessage.......................................... 2–11
2.5 MultipleSessions............................................ 2–11
2.5.1 Enabling and Controlling the Session Configuration . . . . . . . . . . . . . . 2–12
2.5.2 Multiple Sessions using a Terminal Server with TD/SMP . . . . . . . . . . 2–12
2.5.3 Multiple Sessions using SSU Host Software . . . . . . . . . . . . . . . . . . . . 2–12
2.5.4 OpeningAnotherSession................................... 2–12
2.5.5 Restoring an Interrupted Session. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–13
2.5.6 SessionManagement...................................... 2–13
2.6 SessionMenu............................................... 2–13
2.6.1 SelectSession............................................ 2–14
2.6.2 SessionName............................................ 2–14
2.6.3 PagesperSession......................................... 2–14
2.6.4 Soft Character Sets/Session . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–16
2.6.5 Save Settings for All and Restore Settings for All . . . . . . . . . . . . . . . . 2–16
2.6.6 CopySettingsfromMenu................................... 2–17
2.6.7 UpdateSession .......................................... 2–17
2.7 Resetting and Restoring Defaults. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–18
2.7.1 ResetSession............................................ 2–18
2.7.2 RestoreFactoryDefaults................................... 2–18
2.8 DisplayMenu............................................... 2–19
2.8.1 LinesperScreen ......................................... 2–20
2.8.1.1 AutoResize .......................................... 2–20
2.8.2 LinesperPage........................................... 2–20
2.8.3 Review Previous Lines Buffer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–21
2.8.4 Columns per Page, Clear on Change . . . . . . . . . . . . . . . . . . . . . . . . . . 2–22
2.8.5 StatusDisplay........................................... 2–22
2.8.6 ScrollingMode........................................... 2–22
2.8.7 ScreenBackground ....................................... 2–22
2.8.8 CursorDisplay........................................... 2–22
2.8.9 CursorCoupling.......................................... 2–22
2.8.10 WritingDirection......................................... 2–23
2.8.11 Zero................................................... 2–23
2.8.12 AutoWrap.............................................. 2–23
2.8.13 NewLineMode .......................................... 2–23
2.8.14 LockUserPreferences..................................... 2–23
2.8.15 ShowControlCharacters................................... 2–24
2.8.16 CRTSaver.............................................. 2–24
2.8.17 EnergySaver............................................ 2–24
2.8.17.1 WarningBell ......................................... 2–25
2.8.18 Overscan ............................................... 2–25
2.8.19 FramedWindows......................................... 2–25
2.8.20 ScreenAlignment......................................... 2–27
2.9 ColorSet-Up ............................................... 2–28
2.9.1 AssignColors............................................ 2–28
2.9.2 AlternateTextColors...................................... 2–30
2.9.3 DefineColorsDialogBox................................... 2–31
2.9.4 SelectColorMode ........................................ 2–32
2.9.5 ASCIIColorMode ........................................ 2–32
2.9.6 BoldandBlinkStyle ...................................... 2–32
2.9.7 EraseColor ............................................. 2–32
2.9.8 Reverse and Blank Attributes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–33
2.9.9 IntensityAttributes....................................... 2–33
2.10 TerminalTypeMenu ......................................... 2–33
2.10.1 EmulationMode.......................................... 2–33
viii

2.10.2 TerminalIDtoHost....................................... 2–34
2.10.3 VTDefaultCharacterSet .................................. 2–34
2.10.4 PCTermCharacterSet..................................... 2–34
2.10.5 7-BitNRCSCharacters .................................... 2–34
2.10.6 Transmit7-BitControls.................................... 2–34
2.11 ASCIIEmulationMenu....................................... 2–35
2.12 KeyboardMenu............................................. 2–36
2.12.1 KeyboardLanguage....................................... 2–37
2.12.2 DefineKeyEditor ........................................ 2–37
2.12.2.1 Copy of Key Default—Moving a Standard Function . . . . . . . . . . . . 2–38
2.12.2.2 Customization ........................................ 2–39
2.12.2.3 ModifierKeys......................................... 2–39
2.12.2.4 CreatingaNewFunction................................ 2–39
2.12.2.5 Examples of Creating New Functions . . . . . . . . . . . . . . . . . . . . . . 2–39
2.12.2.6 CorrectingaMistake................................... 2–40
2.12.2.7 Creating A New Alphanumeric Key or Keyboard Layout . . . . . . . . 2–40
2.12.2.8 Examples of Creating New Alphanumeric Keys . . . . . . . . . . . . . . . 2–40
2.12.2.9 User-DefinedKeys..................................... 2–41
2.12.2.10 ProgrammingNotes.................................... 2–41
2.12.3 SaveKeyDefinitions ...................................... 2–42
2.12.4 RecallKeyDefinitions ..................................... 2–42
2.12.5 LockKeyDefinitions ...................................... 2–42
2.12.6 CapsLockFunction....................................... 2–42
2.12.7 Keyclick, Warning Bell, and Margin Bell Volume. . . . . . . . . . . . . . . . . 2–42
2.12.7.1 VisibleBell........................................... 2–43
2.12.8 KeyboardEncoding ....................................... 2–43
2.12.9 AutoRepeat............................................. 2–43
2.12.10 DataProcessingKeys...................................... 2–43
2.12.11 ApplicationCursorKeys ................................... 2–43
2.12.12 ApplicationKeypadMode .................................. 2–44
2.12.13 MapPCKeyboardtoVT ................................... 2–44
2.12.14 IgnoreMissingKeyboard................................... 2–44
2.13 CommunicationMenu ........................................ 2–45
2.13.1 Communication Port Select . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–46
2.13.2 WordSize............................................... 2–47
2.13.3 Parity.................................................. 2–47
2.13.4 StopBits ............................................... 2–47
2.13.5 TransmitSpeed .......................................... 2–48
2.13.6 ReceiveSpeed ........................................... 2–48
2.13.7 TransmitFlowControl..................................... 2–48
2.13.8 ReceiveFlowControl...................................... 2–49
2.13.9 FlowControlThreshold.................................... 2–49
2.13.10 Transmit Rate Limit, Fkey Rate Limit. . . . . . . . . . . . . . . . . . . . . . . . . 2–49
2.13.11 IgnoreNullCharacter ..................................... 2–50
2.13.12 LocalEcho.............................................. 2–50
2.13.13 HalfDuplex............................................. 2–50
2.13.14 AutoAnswerback......................................... 2–50
2.13.15 AnswerbackMessage...................................... 2–50
2.13.16 AnswerbackConcealed..................................... 2–51
2.14 ModemMenu............................................... 2–52
2.14.1 EnableModemControl .................................... 2–52
2.14.2 DisconnectDelay......................................... 2–52
2.14.3 ModemHighSpeed ....................................... 2–53
2.14.4 ModemLowSpeed........................................ 2–53
ix

2.15 PrinterMenu............................................... 2–54
2.15.1 PortSelect.............................................. 2–54
2.15.2 PrintMode.............................................. 2–54
2.15.3 PrinterType............................................. 2–55
2.15.4 PrinterCharacterSets..................................... 2–55
2.15.4.1 DEC/ISOCharacterSets ................................ 2–56
2.15.4.2 PCCharacterSets..................................... 2–56
2.15.5 PrintExtent............................................. 2–56
2.15.6 PrintTerminator ......................................... 2–56
2.15.7 SerialPrintSpeed ........................................ 2–56
2.15.8 2-WayCommunication..................................... 2–57
2.15.9 TransmitFlowControl..................................... 2–57
2.15.10 ReceiveFlowControl...................................... 2–57
2.15.11 WordSize............................................... 2–57
2.15.12 Parity.................................................. 2–58
2.15.13 StopBits ............................................... 2–58
2.15.14 SameasReceive.......................................... 2–58
2.16 Tabs... .................................................. 2–58
2.17 Sound..................................................... 2–59
2.18 Set-UpFactoryDefaults....................................... 2–61
3 Desktop Features
3.1 Introduction................................................ 3–1
3.2 InvokingDesktopFeatures .................................... 3–1
3.3 Calculator ................................................. 3–2
3.4 Clock ..................................................... 3–5
3.5 ReviewPreviousLines........................................ 3–7
3.6 CharacterSetTables......................................... 3–7
3.6.1 Show Character Sets feature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–7
3.6.2 Bannermessage.......................................... 3–8
3.7 KeyboardSummary.......................................... 3–8
Part II VT520 ANSI Mode
4 ANSI Control Functions Summary
4.1 Introduction................................................ 4–1
4.2 ControlCharacters........................................... 4–1
4.3 ControlFunctions ........................................... 4–5
4.3.1 SequenceFormat......................................... 4–5
4.3.2 EscapeSequences ........................................ 4–6
4.3.3 ControlSequences ........................................ 4–6
4.3.3.1 Control Sequence Introducer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–6
4.3.3.2 Parameters .......................................... 4–7
4.3.3.3 IntermediateCharacters ................................ 4–8
4.3.3.4 FinalCharacter....................................... 4–8
4.3.4 DeviceControlStrings..................................... 4–8
4.3.5 Using Control Characters in Sequences . . . . . . . . . . . . . . . . . . . . . . . . 4–9
4.3.6 7-Bit Code Extension Technique. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–9
4.4 Working with 7-Bit and 8-Bit Environments . . . . . . . . . . . . . . . . . . . . . . . 4–10
4.4.1 Conventions for Codes Received by the Terminal . . . . . . . . . . . . . . . . . 4–10
4.4.2 Conventions for Codes Sent by the Terminal . . . . . . . . . . . . . . . . . . . . 4–10
4.5 ShowingControlCharacters ................................... 4–11
x

4.6 Terminal Management Functions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–15
4.7 ANSI Control Function Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–16
4.7.1 Sessions Management Control Functions . . . . . . . . . . . . . . . . . . . . . . . 4–16
4.7.2 Window Management Control Functions . . . . . . . . . . . . . . . . . . . . . . . 4–17
4.7.3 Audible Attributes Control Functions . . . . . . . . . . . . . . . . . . . . . . . . . 4–18
4.7.4 Color Selection Control Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–18
4.7.5 Visual Attributes Control Functions . . . . . . . . . . . . . . . . . . . . . . . . . . 4–20
4.7.6 EditingControlFunctions .................................. 4–21
4.7.7 Text Processing Control Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–22
4.7.8 Graphic Character Sets Control Functions. . . . . . . . . . . . . . . . . . . . . . 4–25
4.7.9 Keyboard Processing Control Functions . . . . . . . . . . . . . . . . . . . . . . . 4–27
4.7.10 PrinterControlFunctions .................................. 4–33
4.7.11 Terminal Management Control Functions . . . . . . . . . . . . . . . . . . . . . . 4–34
4.7.12 Terminal Management—Communications Control Functions . . . . . . . 4–39
4.7.13 Terminal Synchronization Control Functions . . . . . . . . . . . . . . . . . . . . 4–41
4.7.14 ReportsControlFunctions.................................. 4–42
4.8 VT52ModeEscapeSequences.................................. 4–45
5 ANSI Control Functions
ANSIConformanceLevels..................................... 5–1
CBT—Cursor Backward Tabulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–3
CHA—Cursor Horizontal Absolute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–3
CHT—Cursor Horizontal Forward Tabulation . . . . . . . . . . . . . . . . . . . . . . 5–4
CNL—CursorNextLine....................................... 5–4
CPL—CursorPreviousLine.................................... 5–5
CPR—Cursor Position Report . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–5
CRM—Show Control Character Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–6
CUB—CursorBackward ...................................... 5–7
CUD—CursorDown.......................................... 5–7
CUF—CursorForward........................................ 5–7
CUP—CursorPosition........................................ 5–8
CUU—CursorUp............................................ 5–8
DA1—Primary Device Attributes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–9
DA2—Secondary Device Attributes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–11
DA3—Tertiary Device Attributes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–12
DCH—DeleteCharacter....................................... 5–13
DDD1,DDD2,DDD3......................................... 5–14
DECAAM—Set/Reset Auto Answerback Mode . . . . . . . . . . . . . . . . . . . . . . 5–15
DECAC—AssignColor ....................................... 5–16
DECALN—Screen Alignment Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–17
DECANM—ANSIMode....................................... 5–18
DECANM Exit—Exiting ANSI (VT52) Mode . . . . . . . . . . . . . . . . . . . . . . . 5–19
DECARM—AutorepeatMode................................... 5–19
DECARR—Select Auto Repeat Rate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–20
DECARSM—Set/Reset Auto Resize Mode . . . . . . . . . . . . . . . . . . . . . . . . . 5–21
DECATC—Alternate Text Color . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–22
DECATCBM—Set/Reset Alternate Text Color Blink Mode. . . . . . . . . . . . . 5–23
DECATCUM—Set/Reset Alternate Text Color Underline Mode . . . . . . . . . 5–23
DECAUPSS—Assigning User-Preferred Supplemental Sets . . . . . . . . . . . 5–24
xi

DECAWM—AutowrapMode ................................... 5–25
DECBBSM—Bold and Blink Style Mode . . . . . . . . . . . . . . . . . . . . . . . . . 5–25
DECBI—BackIndex ......................................... 5–26
DECBKM—Backarrow Key Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–26
DECCANSM—Conceal Answerback Message Mode . . . . . . . . . . . . . . . . . 5–27
DECCAPSLK—CapsLockMode ................................ 5–28
DECCARA—Change Attributes in Rectangular Area . . . . . . . . . . . . . . . . 5–28
DECCIR—Cursor Information Report (Terminal to Host) . . . . . . . . . . . . . 5–30
DECCKD—CopyKeyDefault................................... 5–31
DECCKM—CursorKeysMode.................................. 5–32
DECCKSR—Memory Checksum Report . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–33
DECCOLM—Selecting 80 or 132 Columns per Page . . . . . . . . . . . . . . . . . 5–34
DECCRA—Copy Rectangular Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–35
DECCRTST—CRT Saver Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–36
DECCRTSM—Set/Reset CRT Save Mode . . . . . . . . . . . . . . . . . . . . . . . . . . 5–37
DECDC—DeleteColumn...................................... 5–37
DECDHL—Double-Width, Double-Height Line . . . . . . . . . . . . . . . . . . . . . 5–38
DECDLD—Dynamically Redefinable Character Sets Extension. . . . . . . . . 5–39
DECDMAC—DefineMacro .................................... 5–45
DECDLDA—Down Line Load Allocation . . . . . . . . . . . . . . . . . . . . . . . . . 5–47
DECDWL—Double-Width, Single-Height Line . . . . . . . . . . . . . . . . . . . . . 5–48
DECECM—EraseColorMode .................................. 5–48
DECEKBD—Extended Keyboard Report . . . . . . . . . . . . . . . . . . . . . . . . . 5–49
DECELF—Enable Local Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–51
DECERA—Erase Rectangular Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–52
DECES—EnableSession...................................... 5–53
DECESKM—Enable Secondary Keyboard Language Mode . . . . . . . . . . . . 5–53
DECFI—ForwardIndex....................................... 5–54
DECFRA—Fill Rectangular Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–55
DECFWM—Set/Reset Framed Windows Mode . . . . . . . . . . . . . . . . . . . . . . 5–56
DECHDPXM—Set/Reset Half-Duplex Mode . . . . . . . . . . . . . . . . . . . . . . . 5–56
DECHEM—Hebrew Encoding Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–57
DECHEBM—Hebrew/N-A Keyboard Mapping Mode . . . . . . . . . . . . . . . . . 5–58
DECHWUM—Host Wake-Up Mode (CRT and Energy Saver) . . . . . . . . . . 5–59
DECIC—InsertColumn....................................... 5–59
DECID—IdentifyDevice ...................................... 5–60
DECINVM—InvokeMacro..................................... 5–61
DECIPEM—Enter/Return from IBM ProPrinter Emulation Mode . . . . . . . 5–62
DECKBD—Keyboard Language Selection . . . . . . . . . . . . . . . . . . . . . . . . . 5–63
DECKBUM—Typewriter or Data Processing Keys . . . . . . . . . . . . . . . . . . 5–65
DECKLHIM—Keyboard LED’s Host Indicator Mode . . . . . . . . . . . . . . . . . 5–65
DECKPAM—Keypad Application Modes . . . . . . . . . . . . . . . . . . . . . . . . . . 5–66
DECKPM—KeyPositionMode.................................. 5–66
DECKPNM—Keypad Numeric Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–67
DECLANS—Load Answerback Message . . . . . . . . . . . . . . . . . . . . . . . . . . 5–68
DECLBAN—Load Banner Message . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–69
DECLFKC—Local Function Key Control . . . . . . . . . . . . . . . . . . . . . . . . . 5–70
xii

DECLL—LoadLEDs ......................................... 5–71
DECLRMM—Left Right Margin Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–72
DECLTOD—LoadTimeofDay ................................. 5–72
DECMCM—Modem Control Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–73
DECMSR—Macro Space Report . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–73
DECNAKB—Greek/N-A Keyboard Mapping Mode . . . . . . . . . . . . . . . . . . . 5–74
DECNCSM—No Clearing Screen On Column Change Mode . . . . . . . . . . . 5–74
DECNKM—Numeric Keypad Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–75
DECNRCM—National Replacement Character Set Mode . . . . . . . . . . . . . 5–75
DECNULM—NullMode....................................... 5–76
DECNUMLK—NumLockMode................................. 5–76
DECOM—OriginMode........................................ 5–77
DECOSCNM—Set/Reset Overscan Mode (VT520 only) . . . . . . . . . . . . . . . 5–77
DECPAK—Program Alphanumeric Key . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–78
DECPCCM—Page Cursor-Coupling Mode . . . . . . . . . . . . . . . . . . . . . . . . . 5–80
DECPCTERM—Enter/Exit PCTerm or Scancode Mode . . . . . . . . . . . . . . . 5–81
DECPEX—PrintExtentMode.................................. 5–83
DECPFF—Print Form Feed Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–83
DECPFK—Program Function Key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–84
DECPKA—Program Key Action . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–87
DECPKFMR—Program Key Free Memory Report . . . . . . . . . . . . . . . . . . 5–88
DECPS—PlaySound......................................... 5–89
DECRARA—Reverse Attributes in Rectangular Area . . . . . . . . . . . . . . . . 5–90
DECRC—RestoreCursor...................................... 5–92
DECRLCM—Right-to-Left Copy Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–92
DECRLM—Right-to-Left Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–93
DECRPAK—Report All Modifiers/Alphanumeric Key State . . . . . . . . . . . . 5–94
DECRPDE—Report Displayed Extent . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–95
DECRPFK - Report Function Key Definition . . . . . . . . . . . . . . . . . . . . . . . 5–96
DECRPKT—ReportKeyType .................................. 5–96
DECRPL—Review Previous Lines Mode . . . . . . . . . . . . . . . . . . . . . . . . . . 5–97
DECRPM—Report Mode - Terminal To Host . . . . . . . . . . . . . . . . . . . . . . . 5–98
DECRPSS—Report Selection or Setting . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–102
DECRPTUI—Report Terminal Unit ID . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–104
DECRQCRA—Request Checksum of Rectangular Area . . . . . . . . . . . . . . . 5–105
DECRQDE—Request Displayed Extent . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–105
DECRQKD—Request Key Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–106
DECRQKT—RequestKeyType ................................. 5–107
DECRQM—Request Mode - Host To Terminal . . . . . . . . . . . . . . . . . . . . . . 5–108
DECRQPKFM—Request Program Key Free Memory . . . . . . . . . . . . . . . . 5–111
DECRQPSR—Request Presentation State Report . . . . . . . . . . . . . . . . . . . 5–111
DECRQSS—Request Selection or Setting . . . . . . . . . . . . . . . . . . . . . . . . . 5–112
DECRQTSR—Request Terminal State Report . . . . . . . . . . . . . . . . . . . . . 5–113
DECCTR—Color Table Request . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–114
DECRQUPSS—Request User-Preferred Supplemental Set . . . . . . . . . . . . 5–115
DECRSPS—Restore Presentation State . . . . . . . . . . . . . . . . . . . . . . . . . . 5–116
DECRSTS—Restore Terminal State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–117
xiii

DECRSTS—Restore Terminal Color Table State . . . . . . . . . . . . . . . . . . . . 5–118
DECSACE—Select Attribute Change Extent . . . . . . . . . . . . . . . . . . . . . . 5–119
DECSASD—Select Active Status Display . . . . . . . . . . . . . . . . . . . . . . . . . 5–120
DECSC—SaveCursor ........................................ 5–120
DECSCA—Select Character Protection Attribute . . . . . . . . . . . . . . . . . . . 5–121
DECSCL—Select Conformance Level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–122
DECSCLM—ScrollingMode ................................... 5–123
DECSCNM—Screen Mode: Light or Dark Screen . . . . . . . . . . . . . . . . . . . 5–123
DECSCP—Select Communication Port . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–124
DECSCPP—Select Columns Per Page . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–125
DECSCS—Select Communication Speed . . . . . . . . . . . . . . . . . . . . . . . . . . 5–126
DECSCUSR—Set Cursor Style . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–127
DECSDDT—Select Disconnect Delay Time . . . . . . . . . . . . . . . . . . . . . . . . 5–128
DECSDPT—Select Digital Printed Data Type . . . . . . . . . . . . . . . . . . . . . . 5–129
DECSED—Selective Erase in Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–129
DECSEST—Energy Saver Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–130
DECSEL—Selective Erase in Line . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–131
DECSERA—Selective Erase Rectangular Area . . . . . . . . . . . . . . . . . . . . . 5–132
DECSFC—Select Flow Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–133
DECSIN—SetIconName ..................................... 5–134
DECSKCV—Set Key Click Volume . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–135
DECSLCK—Set Lock Key Style . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–135
DECSLPP—SetLinesPerPage ................................ 5–136
DECSLRM—Set Left and Right Margins . . . . . . . . . . . . . . . . . . . . . . . . . 5–137
DECSMBV—Set Margin Bell Volume . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–138
DECSMKR—Select Modifier Key Reporting . . . . . . . . . . . . . . . . . . . . . . . 5–139
DECSNLS—Set Number of Lines Per Screen . . . . . . . . . . . . . . . . . . . . . . 5–140
DECSPMA—Session Page Memory Allocation . . . . . . . . . . . . . . . . . . . . . 5–141
DECSPP—Set Port Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–142
DECSPPCS—Select ProPrinter Character Set . . . . . . . . . . . . . . . . . . . . . 5–143
DECSPRTT—Select Printer Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–144
DECSR—SecureReset........................................ 5–144
DECSRC—Secure Reset Confirmation . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–146
DECSSCLS—Set Scroll Speed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–146
DECSSDT—Select Status Display (Line) Type . . . . . . . . . . . . . . . . . . . . . 5–147
DECSSL—Select Set-Up Language . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–148
DECST8C—Set Tab at Every 8 Columns . . . . . . . . . . . . . . . . . . . . . . . . . 5–149
DECSTBM—Set Top and Bottom Margins . . . . . . . . . . . . . . . . . . . . . . . . 5–149
DECSTR—Soft Terminal Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–150
DECSTGLT—Select Color Look-Up Table . . . . . . . . . . . . . . . . . . . . . . . . . 5–151
DECSTRL—Set Transmit Rate Limit . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–152
DECSTUI—Setting Terminal Unit ID . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–153
DECSWBV—Set Warning Bell Volume . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–154
DECSWL—Single-Width, Single-Height Line . . . . . . . . . . . . . . . . . . . . . . 5–154
DECSZS—SelectZeroSymbol .................................. 5–155
DECSWT—SetWindowTitle .................................. 5–156
DECTABSR—TabStopReport ................................. 5–157
xiv

DECTCEM—Text Cursor Enable Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–157
DECTID—SelectTerminalID .................................. 5–158
DECTME—Terminal Mode Emulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–159
DECTSR—Terminal State Report—Terminal to Host . . . . . . . . . . . . . . . . 5–160
DECTSR—Terminal State Report (Color Table Report) . . . . . . . . . . . . . . . 5–161
DECTST—Invoke Confidence Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–162
DECUDK—UserDefinedKeys.................................. 5–163
DECUS—UpdateSession...................................... 5–169
DECVCCM—Vertical Cursor-Coupling Mode . . . . . . . . . . . . . . . . . . . . . . . 5–170
DECXCPR—Extended Cursor Position Report . . . . . . . . . . . . . . . . . . . . . . 5–170
DECXRLM—Transmit Rate Limiting . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–171
DL—DeleteLine ............................................ 5–172
DSR—DeviceStatusReports .................................. 5–173
DSR—Cursor Position Report (CPR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–173
DSR—DataIntegrityReport ................................... 5–174
DSR—Extended Cursor Position Report (DECXCPR response) . . . . . . . . . 5–174
DSR—KeyboardReport....................................... 5–175
DSR—MacroSpaceReport..................................... 5–176
DSR—Memory Checksum Report (DECCKSR) . . . . . . . . . . . . . . . . . . . . . 5–177
DSR—Operating Status Report . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–177
DSR—PrinterPortReport .................................... 5–178
DSR—User-Defined Keys Report (VT Level 4 or higher) . . . . . . . . . . . . . . 5–179
ECH—EraseCharacter ....................................... 5–179
ED—EraseinDisplay ........................................ 5–180
EL—EraseinLine........................................... 5–180
HPA—Horizontal Position Absolute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–181
HPR—Horizontal Position Relative . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–181
HT—HorizontalTab.......................................... 5–182
HTS—HorizontalTabSet...................................... 5–182
HVP—Horizontal and Vertical Position . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–183
ICH—InsertCharacter........................................ 5–183
IL—InsertLine ............................................. 5–184
IND—Index................................................ 5–184
IRM—Insert/ReplaceMode .................................... 5–185
KAM—KeyboardActionMode.................................. 5–185
LNM—Line Feed/New Line Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–186
LS—LockingShift ........................................... 5–187
MC—MediaCopy ........................................... 5–188
NEL—NextLine ............................................ 5–191
NP—NextPage ............................................. 5–191
PP—PrecedingPage.......................................... 5–192
PPA—Page Position Absolute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–192
PPB—Page Position Backward . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–193
PPR—Page Position Relative . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–193
RIS—ResettoInitialState .................................... 5–194
RM—ResetMode............................................ 5–195
S7C1T—Send C1 Control Character to the Host . . . . . . . . . . . . . . . . . . . . 5–196
xv

S8C1T—Send C1 Control Character to the Host . . . . . . . . . . . . . . . . . . . . 5–196
SCS—SelectCharacterSet .................................... 5–197
Designating Character Sets (SCS Sequences) . . . . . . . . . . . . . . . . . . . . . . 5–197
SD—PanUp................................................ 5–200
SGR—Select Graphic Rendition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–201
SRM—Local Echo: Send/Receive Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–204
SS—SingleShifts............................................ 5–205
SM—SetMode.............................................. 5–206
SU—PanDown ............................................. 5–207
TBC—TabClear............................................. 5–207
VPA—Vertical Line Position Absolute . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–208
VPR—Vertical Position Relative. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–208
6 SCO Console Emulation
6.1 SCOConsoleEmulationMode.................................. 6–1
6.1.1 Keyboard............................................... 6–2
6.1.1.1 Local Function Keys in SCO Console Mode . . . . . . . . . . . . . . . . . . 6–2
6.1.1.2 PCKeyboard ......................................... 6–2
6.1.1.3 VTKeyboardKeyMapping .............................. 6–6
6.2 VT520 SCO Console Control Sequences . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–7
SCODFK—DefineFunctionKey ................................ 6–7
SCODPCC—Display PC Characters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–8
SCORC—Restore Saved Cursor Position . . . . . . . . . . . . . . . . . . . . . . . . . . 6–9
SCOSC—Save Current Cursor Position . . . . . . . . . . . . . . . . . . . . . . . . . . 6–9
7 Character Sets
7.1 Overview .................................................. 7–1
7.2 CharacterSetsSupported ..................................... 7–1
7.2.1 VTGraphicCharacterSets ................................. 7–1
7.2.2 PCTerm Graphic Character Sets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–2
7.2.3 ControlCharacterSets..................................... 7–3
7.2.4 CharacterSetStructure.................................... 7–3
7.2.5 Characters Not in a Character Set. . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–3
7.3 VTMode .................................................. 7–4
7.3.1 SelectingCharacterSets ................................... 7–4
7.3.2 CharacterSetMappings ................................... 7–4
7.4 PCTermMode .............................................. 7–4
7.4.1 SelectingCharacterSets ................................... 7–4
7.4.2 CharacterSetMappings ................................... 7–5
7.5 SCOConsoleMode........................................... 7–5
7.6 SoftCharacterSets .......................................... 7–5
7.6.1 Designing a Soft Character Set . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–6
7.6.2 Coding the Soft Character Set . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–9
7.6.3 Downloading Soft Characters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–13
7.6.4 Designating the Soft Character Set . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–14
7.6.5 Soft Character Set Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–15
7.6.6 Clearing a Soft Character Set . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–16
xvi

8 Keyboard Processing
8.1 Overview—KeyboardLayout ................................... 8–1
8.2 DECVTLayout............................................. 8–2
8.3 VTLayout-PCTermMode.................................... 8–2
8.4 Enhanced PC Layout - PCTerm Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8–3
8.5 EnhancedPCLayout-VTMode ................................ 8–3
8.5.1 DECVTStyle ........................................... 8–3
8.5.2 IBMPCStyle............................................ 8–4
8.6 MainKeyArray............................................. 8–4
8.6.1 CharacterSets........................................... 8–4
8.6.2 TabKey................................................ 8–4
8.6.3 ModifierKeys............................................ 8–4
8.6.4 CapsLock .............................................. 8–5
8.6.5 LeftAlt ................................................ 8–5
8.6.6 RightAlt ............................................... 8–6
8.6.7 AltGr.................................................. 8–6
8.7 TopRowFunctionKeys....................................... 8–6
8.8 EditingKeypadKeys......................................... 8–6
8.9 CursorKeypadKeys ......................................... 8–7
8.10 NumericKeypadKeys........................................ 8–7
8.11 LocalFunctionKeyDefaults ................................... 8–9
8.11.1 NumericKeypadCompose.................................. 8–14
8.11.2 AccessibilityAids ........................................ 8–15
8.12 ControllingKeyboardLEDs.................................... 8–16
8.13 KeyboardLanguages ......................................... 8–17
8.14 Switching Between Keyboard Languages . . . . . . . . . . . . . . . . . . . . . . . . . . 8–18
8.14.1 KeystrokeProcessing...................................... 8–20
8.14.2 Non-SpacingAccentMarks ................................. 8–20
8.14.3 German ................................................ 8–21
8.14.4 Hebrew ................................................ 8–21
8.15 KeystationNumbers ......................................... 8–21
8.16 Scan Codes Sent in PCTerm Mode for EPC Keyboards . . . . . . . . . . . . . . . 8–23
8.17 Scan Codes Sent in PCTerm Mode for VT Keyboards . . . . . . . . . . . . . . . . 8–27
8.18 Control Codes and Keystrokes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8–28
9 Communications
9.1 Introduction to Communications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–1
9.2 PhysicalLinkLayer.......................................... 9–2
9.2.1 25-PinConnectors ........................................ 9–2
9.2.2 DEC Corporate Modular Jacks (MMJ) . . . . . . . . . . . . . . . . . . . . . . . . . 9–3
9.2.3 Connector Pins Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–3
9.2.3.1 TransmittedData–TXDL ............................... 9–4
9.2.3.2 ReceivedData–RXDL.................................. 9–4
9.2.3.3 RequesttoSend–RTS................................... 9–4
9.2.3.4 CleartoSend–CTS..................................... 9–4
9.2.3.5 DataTerminalReady–DTR .............................. 9–5
9.2.3.6 DataSetReady–DSR................................... 9–5
9.2.3.6.1 Modem Initiated Disconnect. . . . . . . . . . . . . . . . . . . . . . . . . . . 9–5
9.2.3.6.2 Terminal Initiated Disconnect . . . . . . . . . . . . . . . . . . . . . . . . . 9–5
9.2.3.6.3 Modemoffline..................................... 9–6
9.2.3.7 Receive Line Signal Detector–RLSD . . . . . . . . . . . . . . . . . . . . . . . 9–6
9.2.3.8 SpeedIndicator–SPDI .................................. 9–6
9.2.3.9 SpeedSelect–SPDS .................................... 9–7
xvii

9.2.4 Half-DuplexMode ........................................ 9–7
9.2.5 Supported Modem Configurations . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–7
9.2.5.1 CCITT Public Switched Telephone Network (2-wire only) . . . . . . . 9–7
9.2.5.2 CCITT Dedicated Line (2-Wire / 4-Wire) Data Network . . . . . . . . . 9–7
9.2.5.3 European Public Circuit Switched Data Network . . . . . . . . . . . . . 9–8
9.2.5.4 European Public Packet Switched Data Network (PSDN) . . . . . . . 9–8
9.3 DataLinkLayer ............................................ 9–9
9.3.1 7- /8-Bit VT100/VT520 Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–9
9.3.2 FlowControl ............................................ 9–10
9.3.2.1 ReceiveBuffer ........................................ 9–10
9.3.2.2 FlowControlSelection.................................. 9–10
9.3.2.2.1 NoFlowControl.................................... 9–11
9.3.2.2.2 XOFF/XON or XPC Flow Control . . . . . . . . . . . . . . . . . . . . . . . 9–11
9.3.2.2.3 DSR/DTRFlowControl .............................. 9–12
9.3.2.2.4 Software and Hardware Combined Flow Control . . . . . . . . . . . 9–12
9.3.2.2.5 FlowControlThreshold.............................. 9–12
9.3.2.3 Show Control Character Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–13
9.3.2.4 Set-Up on Flow Control Handling . . . . . . . . . . . . . . . . . . . . . . . . . 9–13
9.3.2.5 WhenDisconnectOccurs ................................ 9–13
9.4 Features that Affect Communications . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–13
9.4.1 ClearCommunications..................................... 9–14
9.4.2 Connection.............................................. 9–14
9.4.3 LineDisconnection........................................ 9–14
9.4.4 Break.................................................. 9–15
9.4.4.1 ReceivedBreak ....................................... 9–15
10 Printer Port
10.1 Overview .................................................. 10–1
10.2 SerialPort................................................. 10–1
10.2.1 SerialPortFlowControl ................................... 10–1
10.3 ParallelPort ............................................... 10–2
10.3.1 ParallelPortFlowControl.................................. 10–3
10.4 PrintModes................................................ 10–3
10.4.1 PrinterControllerMode.................................... 10–4
10.5 PrintOperation ............................................. 10–4
10.6 TransmittingPrintData ...................................... 10–4
10.6.1 DECANSI.............................................. 10–4
10.6.2 IBM ProPrinter or Compatible Printer . . . . . . . . . . . . . . . . . . . . . . . . 10–5
10.6.2.1 DataTransmission..................................... 10–5
10.6.3 DEC ANSI with IBM ProPrinter Emulation . . . . . . . . . . . . . . . . . . . . 10–6
10.6.3.1 DataTransmission..................................... 10–7
10.7 PrinterStatus .............................................. 10–7
10.8 Suspending Print Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10–7
10.9 AbortingPrintOperations..................................... 10–7
Part III VT520 ASCII Emulation
xviii

11 ASCII Emulations and Control Functions
11.1 Overview .................................................. 11–1
11.2 ASCIIEmulations ........................................... 11–1
11.2.1 EnhancedMode.......................................... 11–2
11.3 CodingNotation............................................. 11–2
11.3.1 Communication Flow Control with PCTerm Mode . . . . . . . . . . . . . . . . 11–3
11.3.2 ProtectingData .......................................... 11–3
12 ASCII Escape Sequences
12.1 ASCIICommunications....................................... 12–1
12.2 TerminalManagement........................................ 12–4
12.3 KeyboardProcessing ......................................... 12–5
12.4 ScreenProcessing ........................................... 12–10
12.4.1 Rectangular Area Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12–28
12.4.1.1 DrawRectangle....................................... 12–31
12.4.1.2 Swap/Copy/Move ...................................... 12–31
12.5 Printing/SendingData........................................ 12–32
12.5.1 SendingData............................................ 12–32
12.5.2 GraphicsCharacters ...................................... 12–36
13 Defining and Loading ASCII Character Fonts
13.1 CharacterSets.............................................. 13–1
13.1.1 PCTermonUSKeyboard................................... 13–1
13.1.2 WYSE and ADDS Enhanced Personalities . . . . . . . . . . . . . . . . . . . . . . 13–1
13.2 Loading, Defining, and Selecting Character Sets . . . . . . . . . . . . . . . . . . . . 13–3
13.3 DesigningaCharacterFont ................................... 13–5
A VT Keyboard Legend Data
A.1 Compose Processing and Non-spacing Diacritical Marks . . . . . . . . . . . . . . A–1
A.2 VTKeyboards .............................................. A–1
B Enhanced PC Keyboards
B.1 Summary of Non-Spacing Diacritical Marks . . . . . . . . . . . . . . . . . . . . . . . B–1
B.2 EnhancedPCKeyboards ...................................... B–2
C ASCII Keycodes and Local Functions
C.1 PCKeyboard ............................................... C–1
C.2 DECVTKeyboard........................................... C–6
C.3 ASCIILocalFunctions........................................ C–9
D VT520 Termcap Data
D.1 TermcapEmulations ......................................... D–1
D.1.1 TermcapData:........................................... D–1
D.1.2 TerminfoData:........................................... D–2
xix

E ANSI Control Function Index
E.1 ANSI Index by Final Character . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E–1
Glossary
Index
Figures
1–1 SampleVTKeyboardLayout ............................... 1–2
1–2 SamplePCKeyboardLayout................................ 1–2
2–1 Set-Up................................................. 2–1
2–2 Set-Up Language Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–2
2–3 Set-UpSummaryLine..................................... 2–5
2–4 Main and Terminal Actions Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–7
2–5 SessionMenu............................................ 2–13
2–6 Session Page Memory Allocation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–15
2–7 LinesperPage........................................... 2–21
2–8 FramedWindows......................................... 2–26
2–9 ScreenAlignmentDisplay .................................. 2–27
2–10 ColorSet-UpMenu ....................................... 2–28
2–11 AssignColors............................................ 2–29
2–12 AlternateColors.......................................... 2–30
2–13 DefineColors............................................ 2–31
2–14 ASCIIEmulationMenu.................................... 2–35
2–15 KeyboardMenu.......................................... 2–36
2–16 Define Key Editor, Select Function . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–38
2–17 CommunicationMenu ..................................... 2–45
2–18 Communications—Port Select . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–46
2–19 Communication Transmit Speed Menu . . . . . . . . . . . . . . . . . . . . . . . . 2–48
2–20 Communication Fkey Rate Limit Menu . . . . . . . . . . . . . . . . . . . . . . . . 2–49
2–21 Communication Answerback Dialog Box . . . . . . . . . . . . . . . . . . . . . . . 2–51
2–22 ModemMenu............................................ 2–52
2–23 ModemHighSpeedMenu .................................. 2–53
2–24 PrinterMenu............................................ 2–54
2–25 DEC/ISO Character Sets Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–56
2–26 PCCharacterSetsMenu................................... 2–57
2–27 TabSet-UpDialogBox..................................... 2–59
3–1 Calculator with VT Keyboard Layout. . . . . . . . . . . . . . . . . . . . . . . . . . 3–3
3–2 Calculator with PC Keyboard Layout. . . . . . . . . . . . . . . . . . . . . . . . . . 3–4
3–3 ClockFunction........................................... 3–6
4–1 7-bit ASCII Code Table with C0 Control Characters Font (Left
Half)................................................... 4–14
4–2 8-bit ASCII Code Table with C1 Control Characters Font (Right Half)
....................................................... 4–15
7–1 Character Cell Sizes for 24-Line by 80- and 132-Column Fonts . . . . . . 7–6
xx