This parameter adds individual digits from right to left to use in 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 each individual digit in all of the products is then calculated. The check digit passes if this sum modulo Check Digit Modulus is zero.
For 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
6
5
4
3
2
1
Product
6
15
8
12
10
6
Digit add
6+
1+5+
8+
1+2+
1+0+
6=
30
The Check Digit Modulus is 10. It passes because 30 is divisible by 10 (the remainder is 0).
