Omega Engineering OMB-CHARTSCAN 1400, User Manual

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ASCII Code Summary Appendix F
F-4 ChartScan User’s Manual
Decimal Values 00 to 31 – ACG & UCG Descriptions
ASCII Control Codes (00 to 31)
Dec Name Description
Addressed Command Group (
ACG
)
00 Null (
NUL
) Space filler character. Used in output timing for some device
drivers.
01
Start of Header (
SOH
) Marks beginning of message header.
02 Start of Text (
STX
) Marks beginning of data block (text).
03 End of Text (
ETX
) Marks end of data block (text).
04 End of Transmission (
EOT
) Marks end of transmission session.
05
Inquiry (
ENQ
) Request for identification or information.
06 Acknowledgement (
ACK
) “Yes” answer to questions or “ready for next transmission.” Used in
asynchronous protocols for timing.
07
Bell (
BEL
) Rings bell or audible alarm on terminal.
08 Backspace (
BS
) Moves cursor position back one character.
09 Horizontal Tab (
HT
) Moves cursor position to next tab stop on line.
10 Line Feed (
LF
) Moves cursor position down one line.
11
Vertical Tab (
VT
) Moves cursor position down to next “tab line.”
12 Form Feed (
FF
) Moves cursor position to top of next page.
13 Carriage Return (
CR
) Moves cursor to left margin.
14 Shift Out (
SO
) Next characters do not follow ASCII definitions.
15
Shift In (
SI
) Next characters revert to ASCII meaning.
Universal Command Group (
UCG
)
16
Data Link Escape (
DLE
) Used to control transmissions using “escape sequences.”
17
Device Control 1 (
DC1
) Not defined. Normally used for ON controls.
18 Device Control 2 (
DC2
) Usually user-defined.
19 Device Control 3 (
DC3
) Not defined. Normally used for OFF controls.
20
Device Control 4 (
DC4
) Usually user-defined.
21 Negative Acknowledgement (
NAK
) “No” answer to questions or “errors found, re-transmit.” Used in
asynchronous protocols for timing.
22
Synchronous Idle (
SYN
) Sent by asynchronous devices when idle to insure sync.
23
End of Transmission Block (
ETB
) Marks block boundaries in transmission.
24 Cancel (
CAN
) Indicates previous transmission should be disregarded.
25 End of Medium (
EM
) Marks end of physical media, as in paper tape.
26
Substitute (
SUB
) Used to replace a character known to be wrong.
27
Escape (
ESC
) Marks beginning of an Escape control sequence.
28 File Separator (
FS
) Marker for major portion of transmission.
29 Group Separator (
GS
) Marker for submajor portion of transmission.
30
Record Separator (
RS
) Marker for minor portion of transmission.
31 Unit Separator (
US
) Marker for most minor portion of transmission.