Motorola DS4800 Series Product Reference Manual page 257

Digit Add Right To Left Simple Remainder
Each character in the scanned data is assigned a numeric value (see
8-25). The check digit multiplier is reversed in order. Each value representing a character in the scanned data
is multiplied by its corresponding digit in the reversed multiplier, resulting in a product for each character in the
scanned data. The sum of each individual digit in all of the products
calculated. The check digit passes if this sum modulo check digit modulus is equal to the check digit's product.
Example:
Scanned data numeric value is 122459 (check digit is 6)
Check digit multiplier string is 123456
Digit 1 2
Multiplier 6 5
Product 6 10
Digit add 6+ 1+0+ 8+
The check digit modulus is 10. It passes because 19 divided by 10 leaves a remainder of 9.
Digit Add Right to Left Simple Remainder
(6)
2 4 5 9
4 3 2 1
8 12 10 9
1+2+ 1+0= 19 9
OCR Programming 8 - 29
OCR Check Digit Multiplier on page
except for the check digit's product
is then