Hand Held Products 2020 User Manual page 201

Example: Scan the 3-1-3-1 Weighted Modulo 10 Check Character symbol. Also
enter the OCR template:
Then scan the string below:
The reader performs the check character computation below:
(0 x 3 + 1 x 1 + 2 x 3 + 3 x 1 + 4 x 3 + 5 x 1 + 6 x 3 + 5 x 1) modulo 10 = 0
Since the result is zero, the message is considered to be valid, so the reader
outputs the message: 0123456
2-1-2-1 Weighted Modulo 10 Check Character
Starting with the check character and working backward through the message,
the image scanner applies a multiplier of 1, then 2, then 1, then 2, and so on.
When the result of the multiplication is greater than 9, add both digits to the
running sum. This is often referred to as the LUHN formula. One common
application of the LUHN formula is validate credit card numbers. This is the
modulo 10 checking scheme used in MSI Code and in Code 32 Pharmaceutical
(PARAF). To apply this weighting scheme, set the OCR check character to
"0123456789x2x1" or scan the following symbol:
Example: Scan the 2-1-2-1 Weighted Modulo 10 Check Character symbol. Also
enter the OCR template:
Then scan the string below:
The reader performs the check character computation below:
(0 x 1 + 1 x 2 + 2 x 1 + 8 x 2 + 4 x 1 + 5 x 2 + 4 x 1) modulo 10
= (0 + 2 + 2 + (1 + 6) + 4 + (1 + 0) + 4) modulo 10
= 0
Since the result is zero, the message is considered to be valid, so the reader
outputs the message: 012845
2020/4820/4820 i User's Guide
dddddddc
01234565
2-1-2-1 Weighted Modulo 10
Check Character
ddddddc
0128454
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