Data transmission between RF290R and host
3.3 Buffered Read Mode
RF290R
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Configuration Manual, 09/2014, C79000-G8976-C377-01
3.3
Buffered Read Mode
The "Buffered Read Mode" is a mode used to detect transponders in the antenna field of the
reader. In the "Buffered Read Mode", all transponder data is filtered according to the setting
to minimize the amount of data transmitted between reader and host. The "Buffered Read
Mode" is controlled using the following commands:
●
"0x22 Read Buffer"
●
"0x32 Clear data Buffer"
●
"0x33 Initialize Buffer"
You will find further information on the commands in the "Buffered Read Mode" in the section
"Protocols for the Buffered Read Mode (Page 97)".
In this mode, the reader automatically selects the transponders within its antenna field and
reads the required data. The transponder data that is read out is stored in a FIFO data
buffer.
The transponder data that has been read out can be read with the command "[0x22] Read
Buffer". This command reads the first available data set from the data buffer. If you have
already read data, you first need to delete this with the command "[0x32] Clear Data Buffer"
before you can fetch the next data record from the buffer with the read command.
If the "Buffered Read Mode" is activated in the configuration block " CFG1: Interface" the
reader starts to read transponder data immediately after it is turned on. The "Buffered Read
Mode" can be re-initialized with the command "[0x33] Initialize Buffer".
In the "Buffered Read Mode", the reader responds to every valid message with a data or
status protocol. The response also contains the control byte that the reader has received.
Figure 3-11 Sequence when reading in Buffered Read Mode