Rf Tag Communications Command Procedure For Multiaccess Communications - Omron V780 Series User Manual

7 Modbus/TCP Communications
7-4-4 RF Tag Communications Command Procedure for Multiaccess
Communications
When you send an RF Tag communications command with multiaccess communications, the
Reader/Writer communicates with more than one RF Tag in the communications range.
The Reader/Writer will communicate with all of the RF Tags in the communications range within the
communications timeout time (64 max.) and then return a response.
Using a Normal Command (FC03 or FC16)
With a normal multiaccess RF Tag command, two commands are used to exchange the data, one to set
communications and another to get the results.
1
Sending the Command to Set Communications
First, send the command to set communications.
If the Reader/Writer detects even one RF Tag, the results of execution are returned as a normal
response.
If no RF Tags were detected, an RF Tag missing error is returned.
2
Sending the Command to Get the Results
Send the command to get the results.
When you execute the command to get the results, the results of communications with the first
RF Tag that was detected will be returned. The communications results will contain the number
of RF Tags detected, the error code, and, for DATA READ, the UII (EPC code).
If the option is specified, the reception level information is also attached.
3
Repeatedly Getting the Results
Execute the command to get the results once for every RF Tag that was detected.
The number of RF Tags that was detected by the Reader/Writer is included in the response to
the command to get the results. Repeatedly send the command until the number of RF Tags in
the response is 1.
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UHF RFID System V780-series Reader/Writer User's Manual (Z389)