Geometrics G-822A, Руководство по эксплуатации

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Geometrics, Inc. G-822/G-823 Magnetometer Manual
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Set Preamble character
By default the first character of each data stream is a '$'. If another character is desired the
'Px' command is used to change it to the character sent following the 'P'. All characters are
allowed except control characters, digits (0-9), spaces, commas, decimal points, and the
termination char ('*').
Echo Error command
This is not really a command but a message. If a command string is incorrectly sent or
garbled the counter receiving it will change it to 'ERRxx' before echoing it to the next
counter. 'xx' specifies the counter number where the syntax error first occurred. This error
message is interpreted as a command by subsequent counters which echoes the string
unchanged.
Interrogate Setup command
This command allows the operator or logging software to identify which analog channels
and Julian clock fields are being output via the serial port. This information is used to
verify output fields with their hardware channels, and to allow automated calculation of data
field position within each sample being sent out. In addition the software revision number
can be interrogated.
The first character 'I' designates the interrogate command, the second letter designates
which item to interrogate. 'A' specifies interrogating the analog channels, 'J' specifies the
Julian clock, and 'V' specifies the software revision number.
The next two characters specify the counter number '00' through '19'. If the counter number
is omitted, counter 0 will respond.
The addressed counter will insert a response into the command string before sending
echoing it out the serial port to the display terminal or subsequent counter modules.
Subsequent counter modules will ignore these extra response characters and pass them
unmodified down the chain. The response format for each of the three interrogate items are
detailed in the examples below:
Analog channels
The command "IA01" will command counter number one to output characters indicating
which of the six analog channels have been selected for output. Counter 1 will modify the
command string to "IA01:abcdef" where the letters a-f are either an ASCII '0' (channel off)
or '1' (channel on) corresponding to channels 0-5 respectively. If analog channel 0,3, and 4