Geometrics G-822A, Руководство по эксплуатации

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Geometrics, Inc. G-822/G-823 Magnetometer Manual
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the default) and the next line feed are Data bytes from the previous counter(s). Commands
only arrive at subsequent counters after the data transmission is complete. Each command
is identified by the first character, followed by some number of operand characters and a
carriage return.
Only one command can be sent at a time. After each command, you must wait for the
command echo before sending another.
All commands are terminated with a carriage return. A line feed may be sent as well, but it
will be ignored by each counter module. However, at the end of every output data string
there will be a carriage return and a line feed sent. This method insures that the final
counter will have a carriage return/line feed sequence so that if the file is printed it will look
correct on paper. By using the carriage return as the command terminator and stripping
input line feeds insures that dumb terminals (and dumb terminal emulation software) can be
used to control the counter output. (Dumb terminals do not normally transmit line feeds
when <Enter> is pressed).
Here are the current list of commands and the format of each:
Command Format: Description:
----------------- ----------- ----------------------------------
Set Cycle time
Byte 1: 'C' Set time in 0.01 sec increments
2: x MS digit of number ('0'-'9')
3: x 3S digit of number
4: x 2S digit of number
5: x LS digit of number
x: x 5 MS optional char ('0' or '5')
6/7: CR carriage return
[Note: the 5 MS char is optional. It was added
to allow setting the cycle time to more precision
after the initial software release]
Set A/D ch's Byte 1: 'A' Enable/disable A/D channels
2: x '0' = turn off channel; '1' = turn on
3: x select channel # ('0'-'5')
4: x MS digit of counter # ('0' or '1')
5: x LS digit of counter # ('0' - '9')
6: CR carriage return
[Note: characters 4 and 5 can be omitted. If this is done the
command will default to counter 0.]