Scan mode function extension for ASCII readers
3.2 Communication and parameter assignment
ASCII protocol for RF200
Operating Manual, 11/2016, C79000-G8976-C329-04
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The reader is in scan mode as soon as the message frame has been successfully
transmitted.
3.2
Communication and parameter assignment
In the scan mode, data are transferred automatically to the host via the serial interface when
the reader is switched on. The type of data acquisition and transmission is preset in the
reader using parameters.
For commissioning, it is also possible to communicate with the reader during operation. For
this, the host transmits a frame via the serial interface that is processed and acknowledged
in the reader.
The following functions are available for the commissioning:
●
Change parameters
●
Read status (incl. parameters)
The information about the FW/HW version is appended to the parameters when reading.
●
Enable test mode
NOTICE
Loss of transponder information in host-reader communication during operation
When you start the communication between host and reader during commissioning, make
sure that there are no transponders in the antenna field at that time. In this way, the
reader's acknowledgement of a frame from the host can be directly recognized as such.
Otherwise, the reply data of the reader may include transponder data along with the
acknowledgement.
NOTICE
Documenting parameter changes
A change in the communication-relevant parameters “baud rate” and “parity” must be well
documented, because with unknown interface parameter assignment, the reader cannot be
addressed and can also no longer receive user data.
If the interface setting in the reader is no longer known, the host must search for the setting:
using the “read status” frame, for example. It may be necessary to test all combinations
with the “baud rate” and “parity” parameters until a frame is acknowledged as valid.
NOTICE
Changes in scan mode are retentive
Not that changes made in scan mode can be saved retentively. If parameters are saved
retentively in the reader, the reader will still retain these stored values after changing
modes.