User Manual Part 2

RFID Interface
LRP2000 Long Range Passice Reader/Writer
125
*******************************************************************************
ABxF Command 85H: Block Read All
DESCRIPTION
Read a block of data from all RFID tags-in-field or all those with the
specified Family Code.
DISCUSSION
This command is used to read segments of data from contiguous
areas of tag memory. The timeout value is given in 1 msec increments
and can have a value of 1EH to FFFEH (65,534 ms). When the
timeout is set to 0, the controller will return a syntax error. The Block
Read All consists of a Family Code, the reserved byte, a start address
and length, followed by a timeout value and a message terminator as
shown below. If the read length exceeds the last tag address, the
controller will return an syntax error message (error code 21H). A
special termination packet is sent when the timeout expires. A
response is returned after successful completion of the operation or
when the timeout expires.
Field Content
Header 0202H
Command Size Packet length in Bytes excluding the
header, command size, checksum and
terminator Bytes.
Command 85H
Family Code Tag Family Code - 00H = all tags
Reserved Ignored, set to 00H
Start Address 2-Byte value for the starting tag address
Number of Bytes 2-Byte value for the number of bytes to be
read
Timeout 2-Byte value for timeout in 1 ms units. (1EH
- FFFEH)
Checksum Optional Checksum
Terminator 03H