Appendix B

VT100 Family Programming Summary

This appendix provides a summary of VT100 family escape and control sequences. Sequences unique to the VT101, VT102, and VT131, and the VT125 are in Appendix C and Appendix D, respectively.

Control Characters

Name	Character Mnemonic	Octal Code	Function
Null	NUL	000	Ignored when received (not stored in input buffer), used as a fill character.
Enquire	ENQ	005	Transmits answerback message.
Bell	BEL	007	Generates a bell tone.
Backspace	BS	010	Moves cursor to the left one character position, unless it is at the left margin, in which case no action occurs.
Horizontal Tab	HT	011	Moves cursor to the next tab stop, or to the right margin if there are no more tab stops.
Line Feed	LF	012	Causes a line feed or a new line operation. (Refer to line feed/new line mode.)
Vertical Tab	VT	013	Processed as LF.
Form Feed	FF	014	Processed as LF.
Carriage Return	CR	015	Moves cursor to left margin on the current line.
Shift Out	SO	016	Selects G1 character set, as designated by a select character set sequence.
Shift In	SI	017	Selects G0 character set, as designated by a select character set sequence.
Device Control 1	DC1	021	Processed as XON. Causes terminal to continue transmitting characters.
Device Control 3	DC3	023	Processed as XOFF. Causes terminal to stop transmitting all characters except XOFF and XON.
Cancel	CAN	030	If received during an escape or control sequence, sequence is cancelled and the substitution character is displayed.
Substitute	SUB	032	Processed as CAN.
Escape	ESC	033	Processed as a sequence introducer.
Delete	DEL	177	Ignored when received (not stored in input buffer).

ANSI Compatible Sequences

Set Mode
Name	Mnemonic	Mode	Sequence
Line feed/new line	LMN	New line	`ESC [ 20 h`
Cursor key	DECCKM	Application	`ESC [ ? 1 h`
ANSI/VT52	DECANM	ANSI	N/A
Column	DECCOLM	132 column	`ESC [ ? 3 h`
Scrolling	DECSCLM	Smooth	`ESC [ ? 4 h`
Screen	DECSCNM	Reverse	`ESC [ ? 5 h`
Origin	DECOM	Relative	`ESC [ ? 6 h`
Auto wrap	DECAWM	On	`ESC [ ? 7 h`
Auto repeat	DECARM	On	`ESC [ ? 8 h`
Interlace	DECINLM	On	`ESC [ ? 9 h`

Name	Mnemonic	Mode	Sequence*
Line feed/new line	LMN	Line feed	`ESC [ 20 l`
Cursor key	DECCKM	Cursor	`ESC [ ? 1 l`
ANSI/VT52	DECANM	VT52	`ESC [ ? 2 l`
Column	DECCOLM	80 column	`ESC [ ? 3 l`
Scrolling	DECSCLM	Jump	`ESC [ ? 4 l`
Screen	DECSCNM	Normal	`ESC [ ? 5 l`
Origin	DECOM	Absolute	`ESC [ ? 6 l`
Auto wrap	DECAWM	Off	`ESC [ ? 7 l`
Auto repeat	DECARM	Off	`ESC [ ? 8 l`
Interlace	DECINLM	Off	`ESC [ ? 9 l`

* The last character of the sequence is lowercase L (154₈).

Cursor Key Codes Generated
Cursor	ANSI Character Generated
Cursor	Reset (Cursor)	Set (Application)
Up	ESC [ A	`ESC O A`
Down	ESC [ B	`ESC O B`
Right	ESC [ C	`ESC O C`
Left	ESC [ D	`ESC O D`

Keypad Character Selection
Name	Mnemonic	Sequence
Alternate	DECKPAM	`ESC =`
Numeric	DECKPNM	`ESC >`

Key	VT52 Alternate Keypad Mode Off (Numeric Mode)	VT52 Alternate Keypad Mode On	ANSI Numeric Keypad Mode	ANSI Alternate Keypad Mode
0	0	`ESC ? p`	0	`ESC O p`
1	1	`ESC ? q`	1	`ESC O q`
2	2	`ESC ? r`	2	`ESC O r`
3	3	`ESC ? s`	3	`ESC O s`
4	4	`ESC ? t`	4	`ESC O t`
5	5	`ESC ? u`	5	`ESC O u`
6	6	`ESC ? v`	6	`ESC O v`
7	7	`ESC ? w`	7	`ESC O w`
8	8	`ESC ? x`	8	`ESC O x`
9	9	`ESC ? y`	9	`ESC O y`
- (minus)	- (minus)	`ESC ? m`	- (minus)	`ESC O m`
, (comma)	, (comma)	`ESC ? l`*	, (comma)	`ESC O l`*
. (period)	. (period)	`ESC ? n`	. (period)	`ESC O n`
ENTER	Same as RETURN	`ESC ? M`	Same as RETURN	`ESC O M`
PF1	`ESC P`	`ESC P`	`ESC O P`	`ESC O P`
PF2	`ESC Q`	`ESC Q`	`ESC O Q`	`ESC O Q`
PF3	`ESC R`	`ESC R`	`ESC O R`	`ESC O R`
PF4	`ESC S`	`ESC S`	`ESC O S`	`ESC O S`

* The last character of the sequence is lowercase L (154₈).

Select Character Sets (SCS)
Character Set	G0 Designator	G1 Designator
United Kingdom (UK)	`ESC ( A`	`ESC ) A`
United States (USASCII)	`ESC ( B`	`ESC ) B`
Special characters and line drawing set	`ESC ( 0`	`ESC ) 0`
Alternate character ROM	`ESC ( 1`	`ESC ) 1`
Alternate character ROM, special graphics characters	`ESC ( 2`	`ESC ) 2`
Name	Mnemonic	Sequence
Single Shift 2	SS2	`ESC N`
Single Shift 3	SS3	`ESC O`

Character Attributes
Name	Mnemonic	Sequence
Select graphic rendition (no attributes)	SGR	`ESC [ m`
Select graphic rendition (no attributes)	SGR	`ESC [ 0 m`
Select graphic rendition (select attributes, reverse video, or underline as determined by cursor SET-UP feature)	SGR	`ESC [ 4 m`
Select graphic rendition (select attribute, reverse video, or underline as determined by cursor SET-UP feature)	SGR	`ESC [ 7 m`

Scrolling Region
Name	Mnemonic	Sequence
Set top and bottom margins	DECSTBM	`ESC [ Pt ; Pb r`

Cursor Movement Commands
Name	Mnemonic	Sequence
Cursor up	CUU	`ESC [ Pn A`
Cursor down	CUD	`ESC [ Pn B`
Cursor forward (right)	CUF	`ESC [ Pn C`
Cursor backward (left)	CUB	`ESC [ Pn D`
Cursor position	CUP	`ESC [ Pl; Pc H`
Cursor position (home)	CUP	`ESC [ H`
Horizontal and vertical position	HVP	`ESC [ Pl; Pc f`
Horizontal and vertical position (home)	HVP	`ESC [ f`
Index	IND	`ESC D`
Reverse index	RI	`ESC M`
Next line	NEL	`ESC E`
Save cursor (and attributes)	DECSC	`ESC 7`
Restore cursor (and attributes)	DECRC	`ESC 8`

Tab Stops
Name	Mnemonic	Sequence
Horizontal tab set (at current column)	HTS	`ESC H`
Tabulation clear (at current column)	TBC	`ESC [ g`
Tabulation clear (at current column)	TBC	`ESC [ 0 g`
Tabulation clear (all tabs)	TBC	`ESC [ 3 g`

Line Attributes
Name	Mnemonic	Sequence
Double-height top half	DECDHL	`ESC # 3`
Double-height bottom half	DECDHL	`ESC # 4`
Single-width single-height	DECSWL	`ESC # 5`
Double-width single-height	DECDWL	`ESC # 6`

Erasing
Name	Mnemonic	Sequence
Erase in line (cursor to end of line)	EL	`ESC [ K`
Erase in line (cursor to end of line)	EL	`ESC [ 0 K`
Erase in line (beginning of line to cursor)	EL	`ESC [ 1 K`
Erase in line (entire line containing cursor)	EL	`ESC [ 2 K`
Erase in display (cursor to end of screen)	ED	`ESC [ J`
Erase in display (cursor to end of screen)	ED	`ESC [ 0 J`
Erase in display (beginning of screen to cursor)	ED	`ESC [ 1 J`
Erase in display (entire screen)	ED	`ESC [ 2 J`

Reports
Name	Mnemonic	Sequence
Device status report (request status of VT101)	DSR	`ESC [ 5 n`
Response: Terminal OK Terminal not OK	DSR DSR	`ESC [ 0 n` `ESC [ 3 n`
Device status report (report cursor position	DSR	`ESC [ 6 n`
Report cursor position	CPR	`ESC [ Pl; Pc R`
Device attributes (what are you)	DA	`ESC [ c`
Device attributes (what are you)	DA	`ESC [ 0 c`
Identify terminal (what are you)	DECID	`ESC Z` (not recommended)
Device attributes Response	DA	`ESC [ ? 1 ; Ps 0c`

Reset
Name	Mnemonic	Sequence
Reset to initial state	RIS	`ESC c`

Test and Adjustments
Name	Mnemonic	Sequence
Screen alignment display (Fill screen with "Es")	DECALN	`ESC # 8`
Invoke confidence test (power-up test)	DECTST	`ESC [ 2; 1 y`
Invoke confidence test (Data loopback test, requires test connector)	DECTST	`ESC [ 2; 2 y`
Invoke confidence test (repeat power-up test continuously until failure or power-off)	DECTST	`ESC [ 2; 9 y`
Invoke confidence test (repeat data loopback test continuously until failure or power-off, requires test connector)	DECTST	`ESC [ 2; 10 y`

Keyboard LEDs (Indicators)
Name	Mnemonic	Sequence
Load LEDs (all off)	DECLL	`ESC [ 0 q`
Load LEDs (L1 on)	DECLL	`ESC [ 1 q`
Load LEDs (L2 on)	DECLL	`ESC [ 2 q`
Load LEDs (L3 on)	DECLL	`ESC [ 3 q`
Load LEDs (L4 on)	DECLL	`ESC [ 4 q`

VT52 Compatible Mode

Set and Reset Modes
Name	Sequence
Enter ANSI mode	`ESC <`

Keypad Character Selection
Name	Sequence
Enter alternate keypad mode	`ESC =`
Exit alternate keypad mode	`ESC >`

Character Sets
Name	Sequence
Special graphics character set	`ESC F`*
Select US/UK character set (as determined by US/UK character SET-UP feature)	`ESC G`

Cursor Position
Name	Sequence
Cursor up†	`ESC A`
Cursor down†	`ESC B`
Cursor right†	`ESC C`
Cursor left†	`ESC D`
Cursor to home	`ESC H`
Direct cursor address	`ESC Y Pl Pc`‡
Reverse line feed	`ESC I`

† Same when sent from the terminal.

‡ Line and column numbers for direct cursor address are single character codes whose values are the desired number plus (37₈). Line and column numbers start at one.

Erasing
Name	Sequence
Erase to end of line	`ESC K`
Erase to end of screen	`ESC J`

Reports
Name	Sequence
Identify (what are you)	`ESC Z`
Response	`ESC / Z`