The Control Characters

The Control Characters

The first 32 values are non-printing control characters, such as Return and Line feed. You generate these characters on the keyboard by holding down the Control key while you strike another key. For example, Bell is value 7, Control plus G, often shown in documents as ^G. Notice that 7 is 64 less than the value of G (71); the Control key subtracts 64 from the value of the keys that it modifies.

For the text version of the following tables, click Control Characters and Printing Characters.

Control Characters

Char	Oct	Dec	Hex	Control-Key	Control Action
NUL	0	0	0	^@	Null character
SOH	1	1	1	^A	Start of heading, = console interrupt
STX	2	2	2	^B	Start of text, maintenance mode on HP console
ETX	3	3	3	^C	End of text
EOT	4	4	4	^D	End of transmission, not the same as ETB
ENQ	5	5	5	^E	Enquiry, goes with ACK; old HP flow control
ACK	6	6	6	^F	Acknowledge, clears ENQ logon hand
BEL	7	7	7	^G	Bell, rings the bell...
BS	10	8	8	^H	Backspace, works on HP terminals/computers
HT	11	9	9	^I	Horizontal tab, move to next tab stop
LF	12	10	a	^J	Line Feed
VT	13	11	b	^K	Vertical tab
FF	14	12	c	^L	Form Feed, page eject
CR	15	13	d	^M	Carriage Return
SO	16	14	e	^N	Shift Out, alternate character set
SI	17	15	f	^O	Shift In, resume defaultn character set
DLE	20	16	10	^P	Data link escape
DC1	21	17	11	^Q	XON, with XOFF to pause listings; ":okay to send".
DC2	22	18	12	^R	Device control 2, block-mode flow control
DC3	23	19	13	^S	XOFF, with XON is TERM=18 flow control
DC4	24	20	14	^T	Device control 4
NAK	25	21	15	^U	Negative acknowledge
SYN	26	22	16	^V	Synchronous idle
ETB	27	23	17	^W	End transmission block, not the same as EOT
CAN	30	24	17	^X	Cancel line, MPE echoes !!!
EM	31	25	19	^Y	End of medium, Control-Y interrupt
SUB	32	26	1a	^Z	Substitute
ESC	33	27	1b	^[	Escape, next character is not echoed
FS	34	28	1c	^\	File separator
GS	35	29	1d	^]	Group separator
RS	36	30	1e	^^	Record separator, block-mode terminator
US	37	31	1f	^_	Unit separator