HandHeld Entertainment Document Reader 4800dr - Manual (Page 93)

4800dr Barcode Guide 7 - 7
Example: To program the modulo 11 check character from example #8 on page 7-6 , enable the OCR-A font. Scan the Enter
OCR Check Character barcode on page 7-6 , then scan the following hex values in order:
3031323334353637383958
After you enter all the desired hex values, scan the Save barcode on the inside back cover of this manual.
Weighting Options
By default, the check character computation is unweighted. It is possible to use one of two weighted modulo 10 schemes.
Weighting is often used to detect if two neighboring characters are transposed, a common error when an operator keys in data.
3-1-3-1 Weighted Modulo 10 Check Character
Starting with the check character and working backward through the message, the imager applies a multiplier of 1, then 3, then
1, then 3, and so on. This is the checking scheme used in many EAN•UCC symbologies, including U.P.C. and Interleaved 2 of
5 (when a check digit is invoked). To apply this weighting scheme, set the OCR check character to “0123456789x3x1” or scan
the following symbol:
Example: Scan the 3-1-3-1 Weighted Modulo 10 Check Character symbol. Also enter the OCR template:
dddddddc
Then scan the string below:
01234565
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 imager 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:
ddddddc
Then scan the string below:
0128454
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
3-1-3-1 Weighted Modulo 10
Check Character
2-1-2-1 Weighted Modulo 10
Check Character