RFID Communications
117 LRP2000 Passive Reader/Writer
Example
This example locks the family code on all tags with the family code of 02H. Two tags are found and locked.
6.5.21 ABxF Command 94H: SN Fill
DESCRIPTION
Command 94H fills only the RFID tag specified by serial number with a one-byte value over multiple
contiguous addresses.
DISCUSSION
This command is commonly used to clear an RFID tag's memory. It writes a one-byte value repetitively
across a specified range of tag addresses. Only the tag with the specified serial number is affected by this
command. The controller returns a response after the successful fill operation, or when the timeout
expires. The fill function requires a serial number, one data value byte, a starting address, and a fill length.
It fills the specified tag with the data value byte, starting at the specified start address for the specified
number of consecutive bytes. When the fill length is set to 0, the controller writes fill data from the start
address to the end of the tag's 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 returns a syntax error. It
returns a response when done or when the timeout expires.
Command from Host Response form Controller
Field Content Field Content
Header 0202H Header 0202H
Command Size 0005H Response Size 0003H
Command Code 8CH Command Echo 8CH
Family ID 02H Number of Tags 02H
Reserved 00H Status Byte 08H
Timeout 07D0H Checksum 67H
Checksum 95H Terminator 03H
Terminator 03H
Field Content
Header 0202H
Command Size Command length in bytes excluding the header, command size, checksum, and terminator bytes
Command 94H
Family Code Ignored byte, set to 00H
Reserved Ignored byte, set to 00H
Start Address 2-byte value for the starting tag address
Number of Bytes 2-byte value for the length of the fill in number of bytes
Timeout Timeout value given in 1 ms units
Serial Number Serial number of the tag to be addressed
Data Value Value to be written to all addressed bytes
Checksum Optional checksum
Message Terminator 03H