RFID Communications
93 LRP2000 Passive Reader/Writer
Example
Writes 'A' (41H) to the tag starting at address 0005H and continuing for the next consecutive 40 bytes. A
timeout of 2 seconds (07D0H =2000 x 1 ms increments) is set for the completion of the configuration.
6.5.2 ABxF Command 05H: ReadDESCRIPTION
Command 05H reads data from an RFID tag.
DISCUSSION
This command is used to read segments of data from contiguous areas of tag memory. It is capable of
handling up to 1 kByte of data transferred to the host. The timeout value is given in 1 ms increments and
can have a value of 1EH to FFFEH (65,534 ms). When the timeout is set to 0, the controller returns error
21H, syntax error. The Read consists of a start address and length, followed by a timeout value, and a
message terminator as shown below.
Command from Host Response from Controller
Field Content Field Content
Header 0202H Header 0202H
Command Size 0008H Response Size 0001H
Command Code 04H Command Echo 04H
Start address 0005H Checksum FAH
Size 0028H Terminators 03H
Timeout, 2 seconds 07D0H
Data Value Byte 41H
Checksum AEH
Terminators 03H
Field Content
Header 0202H
Command Size Packet length in Bytes excluding the header, command size, checksum and terminator bytes. 0007H
for this command
Command 05H
Start Address 2-byte value for the starting tag address
Number of Bytes 2- byte value for the length of the read in number of bytes
Timeout 2-byte value for timeout in 1 ms units (1EH - FFFEH)
Checksum Optional checksum
Terminator 03H