Agilent Technologies AGC-100, Manual

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Vacuum Gauge Controller AGC-100
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Messages are transmitted to the AGC-100 as ASCII strings in the form of mne-
monic operating codes and parameters. All mnemonics comprise three ASCII
characters.
Spaces are ignored. <ETX> (CTRL C) clears the input buffer in the AGC-100.
HOST AGC-100 Explanation
Mnemonics [and parameters] –––––––––>
<CR>[<LF>] ––––––––––––––––––––––> Receives message with "end of
message"
<––––––––––––––––– <ACK><CR><LF> Positive acknowledgment of a re-
ceived message
When requested with a mnemonic instruction, the AGC-100 transmits the measure-
ment data or parameters as ASCII strings to the HOST.
<ENQ> (CTRL E) must be transmitted to request the transmission of an ASCII
string. Additional strings, according to the last selected mnemonic, are read out by
repetitive transmission of <ENQ>.
If <ENQ> is received without a valid request, the ERROR word is transmitted.
HOST AGC-100 Explanation
Mnemonics [and parameters] –––––––––>
<CR>[<LF>] ––––––––––––––––––––––> Receives message with "end of
message"
<–––––––––––––––––- <ACK><CR><LF> Positive acknowledgment of a re-
ceived message
<ENQ> -––––––––––––––––––––––––> Requests to transmit data
<––––––––––––––– Measurement values
or parameters
<––––––––––––––––––––––– <CR><LF>
Transmits data with "end of mes-
sage"
: :
<ENQ> –––––––––––––––––––––––––> Requests to transmit data
<––––––––––––––– Measurement values
or parameters
<––––––––––––––––––––––– <CR><LF>
Transmits data with "end of mes-
sage"
The strings received are verified in the AGC-100. If an error is detected, a negative
acknowledgment <NAK> is output.
HOST AGC-100 Explanation
Mnemonics [and parameters] –––––––––>
<CR>[<LF>] -–––––––––––––––––––––> Receives message with "end of
message"
***** Transmission or programming error *****
<–––– <NAK><CR><LF> Negative acknowledgment of a re-
ceived message
Mnemonics [and parameters] ––––––––->
<CR>[<LF>] –––––––––––––––––––––> Receives message with "end of
message"
<–––––––––––––––– <ACK><CR><LF> Positive acknowledgment of a re-
ceived message
5.2 Communication
Protocol
Transmission format
Transmission protocol
Reception format
Reception protocol
Error processing
Error recognition protocol