HH490 User Guide
165
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 sub-
set 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 spe-
cific 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
ENQ
Indicates a good command which has been processed.
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 characters.
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.