Omega Vehicle Security 1500 Manual Do Utilizador

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ASCII Code Summary
Appendix F
NetScan User’s Manual
F-3
ASCII Code Details
Decimal Values 00 to 31 – ACG & UCG Descriptions
ASCII Control Codes (00 to 31)
Dec
Name
Description
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.
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.