Geometrics G-822A, Руководство по эксплуатации

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Geometrics, Inc. G-822/G-823 Magnetometer Manual
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$ 69978.347,3797
Counter modules can be daisy chained to form multiple sensor arrays as shown in Figure
13. Note that the output data from counter 0 goes into the input port of counter 1, and so
on. This allows each counter module to append its output data onto the end of the data
stream coming from the previous counter(s). As each counter receives data characters from
previous counters they get echoed to the next. An exception to this is the carriage return/
line feed sequence. Here, the carriage return is replaced by a comma and the line feed is
ignored. Thus one long concatenated string from all counters is output from/through the
last counter, and is terminated by a carriage return/ line feed sequence by the last counter
only. Note that only the first counter outputs a preamble character (the default character is
'$').
7.2 Commands
Commands are sent into the input port of the first counter. Note that commands are the
only characters that enter the first counter. A command string is stored in an incoming
buffer until terminated by a carriage return. The command will then be executed at the end
of the current sample, immediately after the last 'data' byte has been sent out the output port.
Then the command will be echoed to the next counter (or back to the logging computer if it
is the last/only counter in the chain).
Subsequent counter modules in multiple counter arrays differentiate between output data
and commands by assuming that all characters between the data preamble character ('$' is
Figure 13. Schematic diagram of daisy-chained CM-201 counter modules.