Unitech MS652 - Page 101

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MS652 User’s Manual
3.13.6 GS1 DataBar Limited Margin Check
The engine offers four levels of decode security for GS1 DataBar Limited
bar codes. There is an inverse relationship between the level of margin
check and engine aggressiveness. Increasing the level of margin check
can reduce scanning aggressiveness, so select only the level of margin
check necessary.
•Margin Check Level 1 – No clear margin required. This complies with the
original GS1 standard, yet can result in
erroneous decoding of a DataBar Limited bar
code when scanning some UPC symbols that
start with digits 9 and 7.
• Margin Check Level 2 – Automatic risk detection. This level of margin
check can result in erroneous decoding of
DataBar Limited bar codes when scanning
some UPC symbols. If a misdecode is detected,
the engine operates in Level 3 or Level 1.
• Margin Check Level 3 – Margin check level reflects the newly proposed
GS1 standard that requires a five times trailing
clear margin.
• Margin Check Level 4 – Security level extends beyond the standard
required by GS1. This level of margin check
requires a five times leading and trailing clear
margin.