Query Commands
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 device’s
response uses a dash
:Name: Field Usage (Optional)
This command returns the query information from the scanner.
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 command requires a different Tag field, the command is separated from previous commands by a semicolon (;).
Responses
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.
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