Sabio 2010D, Руководство по эксплуатации

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Serial Communications Page 7-16
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Calibrator Address
Following the command word is an address, up to three digits in
length, with the most significant hex digit transmitted first.
This is the decimal address of the calibrator.
If the calibrator does not recognize its unique address, the
remainder of the command will be ignored and no response will be
returned. The addressed instrument will always respond, either
with an acknowledgment, with data or with a negative
acknowledgment if there is an error of some sort.
Data Fields
Some commands have data associated with them. If so, the data
will be returned in one or more fields, separated by commas. The
number of parameters will vary from one command to another, but
will always be the same for a particular command. The length of
each parameter may vary depending upon the data; for example,
how large a numeric value is. The exact meaning of data in the
data field depends entirely upon the command. The data must
consist of printable ASCII characters and cannot include the
start-of-command character (the "@" symbol, by default).
Data Verification Field
The standard Monitor Labs protocol does not support error
checking, however by selecting one of the two data verification
methods supported by the
2010D
, error checking can be added to
both commands and responses.
The data verification field consists of between two and four
characters, depending upon the data verification method
selected. The data verification field is used to verify the
integrity of the received data.
When data verification is enabled, it can be bypassed for
individual commands by replacing the characters with "?"
characters (3F hex). This can be useful for testing purposes.
The calibrator always calculates and returns a checksum in its
response, even if the command checksum is replaced by "?"
characters.