VT Function Support

Table of Contents

Code Extension Functions

Control Coding

Symbol Function Origin 🖳 Console Host
CAN Cancel VT100
SUB Substitute VT100
ESC Escape VT100
DCS Device Control String VT220
CSI Control Sequence Introducer VT100
ST String Terminator VT220
OSC Operating System Command DECterm
PM Privacy Message ``
APC Application Program Command VT420
S7C1T Select 7-bit C1 Transmission VT220 ✓
S8C1T Select 8-bit C1 Transmission VT220 ✓

Character Coding

Symbol Function Origin 🖳 Console Host
LS0 Locking Shift Zero (SI) VT100 ✓
LS1 Locking Shift One (SO) VT100 ✓
LS2 Locking Shift Two VT220 ✓
LS3 Locking Shift Three VT220 ✓
LS1R Locking Shift One Right VT220 ✓
LS2R Locking Shift Two Right VT220 ✓
LS3R Locking Shift Three Right VT220 ✓
SS2 Single Shift Two VT220 ✓
SS3 Single Shift Three VT220 ✓

Graphic Character Sets

Symbol Function Origin 🖳 Console Host
SCS Select Character Set VT100 ✓
DECNRCM (National Replacement) Character Set Mode VT220
DECAUPSS Assign User-Preference Supplemental Set VT320 ✓
DECRQUPSS Request User-Preference Supplemental Set VT320 ✓

Terminal Management Functions

Identification, status, and Initialization

Symbol Function Origin 🖳 Console Host
DA1 Primary Device Attributes VT100 ✓
DA2 Secondary Device Attributes VT220 ✓
DA3 Tertiary Device Attributes VT420 ✓
DSR Device Status Report VT100 ✓
DECID Identify Device VT100
DECTID Select Terminal ID VT510
DECSCL Select Conformance Level VT220
DECSR Secure Reset VT420
DECSRC Secure Reset Confirmation VT420
DECSTR Soft Terminal Reset VT220 ✓
DECSTUI Set Terminal Unit ID (Restricted) VT420
RIS Reset to Initial state VT100 ✓

Emulations

Symbol Function Origin 🖳 Console Host
DECPCTERM Enter/Exit PC Term Mode from DEC VT mode VT420PC
DECTME Terminal Mode Emulation VT510

Set-Up

Symbol Function Origin 🖳 Console Host
DECSSL Select Set-Up Language VT510
DECCRTSM CRT Save Mode (not required) VT510
DECOSCNM Overscan Mode VT510
DECSRFR Select Refresh Rate VT510
DECLTOD Load Time of Day VT510
DECLBAN Load Banner Message VT510

Display Coordinate System and Addressing

Active Position and Cursor

Symbol Function Origin 🖳 Console Host
DECTCEM Text Cursor Enable Mode VT220
DECSCUSR Set Cursor Style VT510 ✓

Margins and Scrolling

Symbol Function Origin 🖳 Console Host
DECSTBM Set Top and Bottom Margin VT100 ✓
DECSLRM Set Left and Right Margin VT420 ✓
DECLRMM Left Right Margin Mode VT420
DECOM Origin Mode VT100
DECSCLM Scrolling Mode VT100
IND Index VT100 ✓
RI Reverse Index VT100 ✓
DECFI Forward Index VT420 ✓
DECBI Back Index VT420 ✓
DECSSCLS Set Scroll Speed VT510

Cursor Movement

Symbol Function Origin 🖳 Console Host
BS Backspace VT100 ✓
LF Line Feed VT100 ✓
VT Vertical Tab VT100 ✓
FF Form Feed VT100 ✓
CR Carriage Return VT100 ✓
NEL Next Line VT100 ✓
LNM Line Feed/New Line Mode VT100
CUU Cursor Up VT100 ✓
CUD Cursor Down VT100 ✓
CUF Cursor Forward VT100 ✓
CUB Cursor Backward VT100 ✓
CUP Cursor Position VT100 ✓
HVP Horizontal/Vertical Position VT100 ✓
DSR-CPR Device Status Report (Cursor Position Report) VT100
DSR-XCPR Device Status Report (Extended Cursor Position Report) VT340 VT420
CHA Cursor Horizontal Absolute VT510 ✓
CNL Cursor Next Line VT510 ✓
CPL Cursor Previous Line VT510 ✓
HPA Horizontal Position Absolute VT510 ✓
HPR Horizontal Position Relative VT510 ✓
VPA Vertical Line Position Absolute VT510 ✓
VPR Vertical Position Relative VT510 ✓

Horizontal Tabulation

Symbol Function Origin 🖳 Console Host
HT Horizontal Tab VT100 ✓
HTS Horizontal Tabulation Set VT100 ✓
TBC Tabulation Clear VT100 ✓
CBT Cursor Backward Tabulation VT510 ✓
CHT Cursor Horizontal Forward Tabulation VT510 ✓
DECST8C Set Tab at every 8 columns VT420PC ✓

Page Size and Arrangement

Symbol Function Origin 🖳 Console Host
DECCOLM Column Mode VT100
DECNCSM No Clear Screen on column Mode VT510
DECSCPP Set Columns Per Page VT340 VT420
DECSLPP Set Lines Per Page VT340 VT420

Page Movement

Symbol Function Origin 🖳 Console Host
NP Next Page VT340 VT420 ✓
PP Preceding Page VT340 VT420 ✓
PPA Page Position Absolute VT340 VT420 ✓
PPR Page Position Relative VT340 VT420 ✓
PPB Page Position Backward VT340 VT420 ✓

Status Display

Symbol Function Origin 🖳 Console Host
DECSASD Select Active Status Display VT340 VT320
DECSSDT Select Status Display Type VT340 VT320

Right to Left

Symbol Function Origin 🖳 Console Host
DECRLM Right to Left Mode VT510
DECRLCM Right to Left Copy Mode VT510
DDD1 VT100 mode Hebrew VT510
DDD2 VT100 mode Hebrew VT510
DDD3 VT100 mode Hebrew VT510

Window Management

Symbol Function Origin 🖳 Console Host
DECHCCM Horizontal Cursor Coupling Mode VT340 VT420
DECVCCM Vertical Cursor Coupling Mode VT340 VT420
DECPCCM Page Cursor Coupling Mode VT340 VT420
DECRQDE Request Displayed Extent VT340 VT420 ✓
DECSNLS Select Number of Lines per Screen (exception) VT420
DECARSM Auto Resize Mode DECterm VT420
SU Pan Down VT340 VT420 ✓
SD Pan Up VT340 VT420 ✓

Visual Attributes and Renditions

Symbol Function Origin 🖳 Console Host
DECSCNM Screen Mode VT100

Line Renditions

Symbol Function Origin 🖳 Console Host
DECSWL Single Width Line VT100 ✓
DECDWL Double Width Line VT100 ✓
DECDHLT Double Height Line Top VT100
DECDHLB Double Height Line Bottom VT100

Character Renditions

Symbol Function Origin 🖳 Console Host
SGR Select Graphic Rendition VT100 ✓

Audible Indicators

Symbol Function Origin 🖳 Console Host
BEL Warning Bell VT100 ✓
DECSKCV Set Keyclick Volume VT510
DECSWBV Set Warning Bell Volume VT510
DECSMBV Set Margin Bell Volume VT510

Editing Functions

DEC Private

Symbol Function Origin 🖳 Console Host
IRM Insert/Replacement Mode VT102
ICH Insert Character VT102 ✓
DCH Delete Character VT102 ✓
IL Insert Line VT100 ✓
DL Delete Line VT100 ✓
DECIC Insert Column VT420 ✓
DECDC Delete Column VT420 ✓
ECH Erase Character VT100 ✓
EL Erase in Line VT100 ✓
DECSEL Selective Erase in Line VT220 ✓
ED Erase in Display VT100 ✓
DECSED Selective Erase in Display VT220 ✓
DECSCA Select Character Attribute (selective erase) VT220 ✓

OLTP Features

Rectangular Area Operations

Symbol Function Origin 🖳 Console Host
DECCRA Copy Rectangular Area VT420 ✓
DECFRA Fill Rectangular Area VT420 ✓
DECERA Erase Rectangular Area VT420 ✓
DECSERA Selective Erase Rectangular Area VT420 ✓
DECCARA Change Attribute in Rectangular Area VT420 ✓
DECRARA Reverse Attribute in Rectangular Area VT420 ✓
DECSACE Select Attribute Change Extent Mode VT420 ✓

Data Integrity

Symbol Function Origin 🖳 Console Host
DECRQCRA Request Checksum of Rectangular Area VT420 ✓
DSR-DECCKSR Device Status Report (Memory Checksum) VT420

Macros

Symbol Function Origin 🖳 Console Host
DECDMAC Define Macro VT420 ✓
DECINVM Invoke Macro VT420 ✓
DSR-MSR Device Status Report (Macro Space Report) VT420

Saving and Restoring Terminal State

Cursor Save Buffer

Symbol Function Origin 🖳 Console Host
DECSC Save Cursor VT100 ✓
DECRC Restore Cursor VT100 ✓

Terminal State Interrogation

Symbol Function Origin 🖳 Console Host
DECRQM Request Mode VT320 ✓
DECNKM Numeric Keypad Mode VT320
DECRQSS Request Selection or Setting VT320 ✓
DECRQPSR Request Presentation State Report VT320 ✓
DECRSPS Restore Presentation State VT320 ✓
DECRQTSR Request Terminal State Report VT320 ✓
DECRSTS Restore Terminal State VT320 ✓

Keyboard Processing Functions

Symbol Function Origin 🖳 Console Host
DECARM Autorepeat Mode VT100
DECBKM Backarrow Key Mode VT420
DECCKM Cursor Keys Mode VT100
DECKBUM Keyboard Usage Mode VT320
DECKPAM Keypad Application Mode VT100 ✓
DECKPM Key Position Mode VT420
DECKPNM Keypad Numeric Mode VT100 ✓
DECNKM Numeric Keypad Mode VT320
DSR-KBD Device Status Report (keyboard status) VT220
KAM Keyboard Action Mode VT220
DECLFC Local Functions Control VT420
DECLFKC Local Function Key Control VT420
DECSMKR Select Modifier Key Reporting VT420
DECHEBM Hebrew Keyboard Map mode VT510
DECHCEM Hebrew Encoding Mode VT510
DECNAKB NA/Greek Selection VT510
DECESKM Secondary Keyboard Language Mode VT510
DECSLCK Set Lock Key Style VT510
DECKBD Keyboard Dialect Selection VT510
DECNUMLK NumLock Mode VT510
DECCAPSLK CapsLock Mode VT510
DECKLHIM Keyboard LEDs Host Indicator Mode VT510
DECLL Load LEDs VT100

Soft Key Mapping (UDK)

Symbol Function Origin 🖳 Console Host
DECUDK User Defined Keys VT220
DSR-UDK Device Status Report (UDK lock) VT220
DECPKA Program Key Action VT510
DECPFK Program Function Key VT510
DECPAK Program Alphanumeric Key VT510
DECCKD Copy Key Default VT510
DECRQPKFM Program Key Free Memory Inquiry VT510
DECRQKT Inquire a Key Type VT510
DECRQKD Inquire a Key Definition VT510

Soft Fonts (DRCS)

Symbol Function Origin 🖳 Console Host
DECDLD Downline Load VT220 ✓

Printing

Symbol Function Origin 🖳 Console Host
DECPEX Print Extent Mode VT220
DECPFF Print Form Feed Mode VT220
DSR-PP Device Status Report (printer port) VT220
MC Media Copy VT220
DECSPRTT Select Printer Type VT510
DECSDPT Select Digital Printed Data Type VT510
DECSPPCS Select Proprinter Character Set VT510

Terminal Communication and Synchronization

Symbol Function Origin 🖳 Console Host
BREAK BREAK VT100
XON XON VT100
XOFF XOFF VT100
ENQ Enquiry VT100 ✓
SRM Send Receive Mode VT220
DECXRLM Transmit Rate Limiting Mode VT420
DECMCM Modem Control Mode VT510
DECAAM Auto Answerback Mode VT510
DECLANS Load Answerback Message VT510
DECCANSM Conceal Answerback Message Mode VT510
DECNULM Ignore Null Mode VT510
DECHPDXM Half Duplex Mode VT510
DECSFC Select Flow Control VT510
DECSDDT Select Disconnect Delay Time VT510
DECSTRL Set Transmit Rate Limit VT510
DECSCS Select Communication Speed VT510
DECSCP Select Communication Port VT510
DECSPP Set Port Parameter VT510

Text Locator Extension

Symbol Function Origin 🖳 Console Host
DECEFR Enable Filter Rectangle UWS
DECELR Enable Locator Reports UWS
DECLKD Locator Key Definition UWS
DECLRP Locator Report UWS
DECRQLP Request Locator Position UWS
DECSLE Select Locator Events UWS
DSR-LS Device Status Report (Locator Status) UWS

Session Management Extension

Symbol Function Origin 🖳 Console Host
DECES Enable Sessions VT340 VT420

Documented Exceptions

Symbol Function Origin 🖳 Console Host
DECANM ANSI/VT52 Mode VT100 ✓
DECALN Screen Alignment VT100 ✓
DECAWM Autowrap Mode VT100
DECTST Invoke Confidence Test VT100
CRM Control Representation Mode VT100

Generated on 11/12/2025 11:14:29