This parameter changes the order of the numeric values the check digit multiplier uses with the Check Digit Modulus.
Each character in the scanned data is assigned a numeric value (see OCR Check Digit Multiplier). 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 these products is computed. The check digit passes if this sum modulo Check Digit Modulus is zero.
For example:
Scanned data numeric value is
132459
(check digit is 9)
Check digit multiplier string is
123456
Digit
1
3
2
4
5
9
Multiplier
6
5
4
3
2
1
Product
6
15
8
12
10
9
Product add
6+
15+
8+
12+
10+
9=
60
The Check Digit Modulus is 10. It passes because 60 is divisible by 10 (the remainder is 0).
