Metrologic Instruments MS951 Longitudinal Redundancy Check LRC, Record Header/Terminator Select

Enter/Exit Program Mode

* *

Longitudinal Redundancy Check (LRC)

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 LRC Calc+ Transmit RS232

R 5 8

**Disable LRC Calc+ Transmit RS232

R 5 9

Start LRC on First RS232 Byte

R A 0

**Start LRC on Second RS232 Byte

R

9

9

Record Header/Terminator Select

** CR On

When this option is on, the scanner will transmit a

Carriage Return after each bar code.

2

CR Off

T

R

1

T

R

** LF On

When this option is on, the scanner will transmit a Line

Feed after each bar code.

4

LF Off

T

R

3

T

R

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