Several special characters can be used to query the device about its settings.
What is the default value for the setting(s).
What is the device's current value for the setting(s).
What is the range of possible values for the setting(s). (The de-
vice's response uses a dash (-) to indicate a continuous range of
values. A pipe (|) separates items in a list of non-continuous val-
Tag Field Usage
When a query is used in place of a Tag field, the query applies to the entire set
of commands available for the particular storage table indicated by the Storage
field of the command. In this case, the SubTag and Data fields should not be
used because they are ignored by the device.
SubTag Field Usage
When a query is used in place of a SubTag field, the query applies only to the
subset of commands available that match the Tag field. In this case, the Data
field should not be used because it is ignored by the device.
Data Field Usage
When a query is used in place of the Data field, the query applies only to the
specific command identified by the Tag and SubTag fields.
Concatenation of Multiple Commands
Multiple commands can be issued within one Prefix/Storage sequence. Only
the Tag, SubTag, and Data fields must be repeated for each command in the
sequence. If additional commands are to be applied to the same Tag, then the
new command sequence is separated with a comma (,) and only the SubTag
and Data fields of the additional command are issued. If the additional com-
mand requires a different Tag field, the command is separated from previous
commands by a semicolon (;).
The device responds to serial commands with one of three responses:
ACK Indicates a good command which has been processed.
ENQ Indicates an invalid Tag or SubTag command.
NAK Indicates the command was good, but the Data field entry was out of the
allowable range for this Tag and SubTag combination, e.g., an entry for a
minimum message length of 100 when the field will only accept 2 charac-
When responding, the device echoes back the command sequence with the
status character inserted directly before each of the punctuation marks (the
period, exclamation point, comma, or semicolon) in the command.
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