- 84 - © 2018 unitech Electronics Co., Ltd. All rights reserved.unitech is a registered trademark of unitech Electronics Co., Ltd.MS652 User’s Manual3.13.6 GS1 DataBar Limited Margin CheckThe engine offers four levels of decode security for GS1 DataBar Limitedbar codes. There is an inverse relationship between the level of margincheck and engine aggressiveness. Increasing the level of margin checkcan reduce scanning aggressiveness, so select only the level of margincheck necessary.•Margin Check Level 1 – No clear margin required. This complies with theoriginal GS1 standard, yet can result inerroneous decoding of a DataBar Limited barcode when scanning some UPC symbols thatstart with digits 9 and 7.• Margin Check Level 2 – Automatic risk detection. This level of margincheck can result in erroneous decoding ofDataBar Limited bar codes when scanningsome 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 proposedGS1 standard that requires a five times trailingclear margin.• Margin Check Level 4 – Security level extends beyond the standardrequired by GS1. This level of margin checkrequires a five times leading and trailing clearmargin.
