ZBA ZB-3062, Руководство пользователя

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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
a. Weighted Modulo 10 Check Character
Since the result is zero, the message is considered to be valid, so the reader outputs the message: 0123456
b. 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:
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
OCR ISBN Application Example
One application of OCR is to read the ISBN characters typically encoded using the OCR-A or OCR-B font. This is especially useful when the ISBN number
is not encoded in an EAN-13 bar code. The following example shows how to configure the imager to read the ISBN strings on books in Japan. After you
have followed the steps below, you will be able to scan the following ISBN number or the additional data below it, depending on the line of text at which the
imager is aimed.
1. Scan the OCR-B On bar code
2. Program the user-defined variable “g” to comprise the ten digits plus the dash: 0123456789-
3. In Japan, it is common for two fields to follow the ISBN number, the three digit price field, and the four digit price field. The first field typically starts
with a “C” (uppercase c), followed by four digits. The second field typically starts with a “P” or a yen symbol, followed by three or four digits, followed by
an “E.” Program the user-defined variable “h” to comprise the “P” and the yen symbol (represented by a backslash). P\
4. Scan the symbol below to set up three templates to handle the ISBN number, the three digit price field, and the four digit price field.
5. Finally, set up the ISBN check digit, which is a special position-weighted modulo 11 checksum. The imager automatically invokes the ISBN checksum
for template rows that are: