User Manual

Table Of Contents
Standard RFID Interface
LRP75 Long Range Passive Reader/Writer 19
In the first case, the RFID interface will first read all tag addresses
affected by the transaction so that data not requested by the host is
not returned or written to. For example, when you request a write to
tag addresses 2 through 5 (4 bytes), the LRP will first read the tag
data at addresses 0 through 7 (8 bytes), and then write to those
addresses with the new data in addresses 2 through 5.
When a write or read operation is executed at a starting address other
than the first byte of a block, the blocks with partial data will also be
included in the operation. For example, a four byte read from an odd
address will take twice as long since the LRP75 will read 8 bytes.
NOTE:To make your application as efficient as possible, design your
tag accesses in 4-byte blocks starting on a the first byte of a
block.
5.4 ABx Error Codes
The LRP75 returns an error if it encounters a fault during operation.
Table 5-2 list the possible error codes in Hexadecimal format.
Table 5-2: ABx Error Codes
Error Code Description
05H Block Read has failed
06H Block Write has failed
08H Search Tag Operation failed
21H Syntax error
0DH Command Read error. You will receive a Command Read
error if you send another command while the LRP75 is in
Continuous Read mode.
0FH Command Read SN and Data error. You will receive a
Command Read error if you send another command while
the LRP75 is in Continuous Read SN and Data mode.