User's Manual

Table Of Contents
ABxS Command 86 (86H): Block Write All
DESCRIPTION
Write a block of data to all RFID tags or all tags with the same Family ID.
DISCUSSION
This command is used to write segments of data to contiguous areas of tag
memory. It is capable of transferring up to 48 bytes of data transferred from
the Host with one command. The timeout value is given in 1 msec incre
-
ments and can have a value of 1EH to FFFEH (65,534 ms). When the time
-
out is set to 0, the LRP820 will return a syntax error.
The Block Write consists of a Tag Family ID and an Anticollision Index,
start address followed by the data stream to be written to the RFID tag. If the
write range exceeds the last tag address, the LRP820 will return error mes
-
sage 21H, invalid format.
The data to be written to the tag is contained in the LSB of the register, and
the MSB is always 00H.
The LRP820 returns a response when the timeout expires. If the
Anticollision Index is 0 the command returns a response after the successful
operation on 1 tag, or when the timeout expires.
Field Remarks
Command Command number in hex preceded by AAH
Family ID Tag Family ID - 00H = all tags
Anticollision Index Number of tags expected
Start Address The tag address where the write will start
Write Length The number of tag addresses to be written to in bytes
Timeout Timeout value given in 1 ms units (1EH - FFFEH)
Write Data The data to be written (1-48 bytes)
Message Terminator FFFFH
NOTE:
This command can not be used over a MUX32 interface.
Copyright © 2000 Escort Memory Systems
68 LRP820-Series Long-Range Passive Reader/Writer