Longitudinal Redundancy Check
A Longitudinal Redundancy Check (LRC) is an error checking character that is calculated
across a sequence of data characters. It is determined by eXclusive ORing (XOR) the
characters to be checked, starting with an initial value of 00H.
The result, an “LRC byte” is then transmitted following the data stream and used by the
receiving computer to determine if the information was received correctly. In the scanner’s case,
XOR is performed prior to adding parity bits.
When the LRC is enabled, the scanner defaults to starting the LRC on the second byte of
information transmitted. Optionally, the calculation can start on the first byte transmitted.
Enable Transmit of LRC Calculation
- The scanner outputs on LRC
check character after the bar code.
*
Disable Transmit of LRC Calculation.
*
Start LRC on First Byte
- The scanner will calculate the LRC check
digit starting with the first character.
Start LRC on Second Byte
- The scanner will calculate the LRC check
digit starting with the second character.
Block Check Character
*
Enable NCR BCC
Disable NCR BCC
Character Replacements
To replace a character:
1. Scan the
enter/exit configuration mode
bar code on page 1.
2. Scan the
character to replace code
(shown below).
3. Scan the ASCII code byte value of the character you wish to replace. Refer to the ASCII
Reference Table in the Code Byte Usage section of this manual.
4. Scan the
replacement character
bar code (shown below).
5. Scan the ASCII code byte value of the replacement character.
6. Scan the
enter/exit configuration mode
bar code on page 1.
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Copyright 2012 unitech Electronics Co., Ltd. All rights reserved. Unitech is a registered trademark of unitech Electronics Co., Ltd.
