Rf Tag Memory Error Correction - Omron V680 series User Manual

Section 4
Functions

RF Tag Memory Error Correction

The WRITE WITH ERROR CORRECTION command (QW) can be used to write an RF Tag memory check
code and error correction code to the five bytes of memory after the write data. The READ WITH ERROR
CORRECTION command (QR) performs a tag memory check and makes 1-bit memory error corrections.
When a 1-bit memory error is corrected, a warning
that a 1-bit memory error occurred is given by
returning an end code of 77, and the normal data
with the error corrected will be returned. When a 2-
bit or larger memory error is detected, a memory
error (end code 76) saying that error correction was
not possible is given and the read data will not be
returned.
For details on the command format, refer to READ WITH ERROR CORRECTION (QR) and WRITE WITH ERROR CORREC-
TION (QW).
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 Example of Using the Memory Error Correction Function
The following example shows how to perform a data check for addresses 0010 to 0015 (hex).
1. Send the WRITE WITH ERROR
CORRECTION (QR) command.
Command:
QWSTH10010313233343536*[CR]
3. Send the READ WITH ERROR
CORRECTION (QW) command.
Command: QRSTH100100006*[CR]
 Response When Read Data Is Correct:
QR0010313233343536*[CR]
 Response When a 2-bit or Longer Memory
Error Is Detected:
QR76*[CR]
RFID System
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User's Manual
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Address
0000
H
0001
H
Area start
address
Area end
address
Memory check code (leftmost)
Memory check code (rightmost)
Error correction code (leftmost)
Error correction code (mid)
Error correction code (rightmost)
2. Write data is written to addresses 0010 to
0015 (hex). The RF Tag memory check code
and a 5-byte error correction code are written
to addresses 0016 to 001A (hex).
Address (hex)
0010 31
0011 32
33
0012
34
0013
35
0014
36
0015
FD
0016
11
0017
0018 00
0C
0019
3C
001A
 Response When a 1-bit Memory Error Is
Corrected:
QR7710313233343536*[CR]
Memory check
code calculation
area
Error correction
code calculation
area
Write data
Memory check code
( )
Calculation area
Memory check code (leftmost)
Memory check code (rightmost)
Memory check code (leftmost)
Memory check code (mid)
Memory check code (rightmost)