Motorola DS3508, Product Reference Manual

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OCR Programming 10 - 27
OCR Check Digit Validation
Parameter # F1h B6h
Use
OCR Check Digit Validation
to protect against scanning errors by applying a check digit validation scheme. The
following is a list of options.
None
No check digit validation, indicating no check digit is applied. This is the default.
Product Add Left to Right
Each character in the scanned data is assigned a numeric value (see OCR Check Digit Multiplier on page 10-26).
Each digit representing a character in the scanned data is multiplied by its corresponding digit in the multiplier, and
the sum of these products is computed. The check digit passes if this sum modulo Check Digit Modulus is zero.
Example:
Scanned data numeric value is 132456 (check digit is 6)
Check digit multiplier string is 123456
Digit 1 3 2 4 5 6
Multiplier 1 2 3 4 5 6
Product 1 6 6 16 25 36
Product add 1+ 6+ 6+ 16+ 25+ 36= 90
The Check Digit Modulus is 10. It passes because 90 is divisible by 10 (the remainder is zero).
*No Check Digit
(00h)
Product Add Left to Right
(03h)