RF290R
Configuration Manual, 09/2014, C79000-G8976-C377-01
97
Protocols for the Buffered Read Mode
10
10.1
Sequence in Buffered Read Mode
In Buffered Read Mode, the reader itself reads data from every transponder within the
antenna field. This mode must be activated in the "CFG1: COM interface (Page 23)"
configuration block and in the "CFG11: Read mode - read data (Page 31)" and "CFG12:
Read mode - filter (Page 34)" configuration blocks.
The queried transponder data sets are saved in a FIFO buffer on the reader. The Buffered
Read Mode operates independently of host commands and starts immediately after being
turned on or the "[0x64] System Reset (Page 48)" command.
To read out queried transponder data sets, you require two commands. In the figure below,
you can see the basic sequences in the Buffered Read Mode.
Host → reader
[0x22] Read Buffer
Command to the reader to read
out data.
typ. 6 ms
Host ← reader
Status e.g. = {0x92}
no valid data
There are no data sets in the
data buffer.
...
...
...
Host → reader
[0x22] Read Buffer
Command to the reader to read
out data.
typ. 6 ms
Host ← reader
Status e.g. = OK and n data
sets
There are data sets in the data
buffer.
n data sets are transferred to
the host.
...
...
...
Host → reader
[0x32] Clear Data Buffer
Command to the reader to de-
lete the read data sets.
typ. 6 ms
Host ← reader
Status e.g. = OK
The n read out data sets were
deleted from the buffer.
The host waits for a reply from the reader.
The host can handle other tasks, for example communicating with other readers.
You can obtain further information on the capacity of the data buffer with the command
"[0x31] Read Data Buffer Info (Page 100)".
