Ocr isbn application example, Ocr isbn application example -8 – HandHeld Entertainment Document Reader 4800dr User Manual

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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 barcode. 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

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).

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:

1.) at least fourteen characters long,

2.) whose first four characters are the letters “ISBN,”

3.) whose last character is a check character, and

4.) when the modulo 11 check character “0123456789X” is programmed.

Please note that all these commands can be combined into a single serial programming command:

OCRENA2,TMP”ISBNggggggggggggctCdddd hdddEtCdddd

hddddE”,GPG”0123456789-”,GPH”P\”,CHK”0123456789X”.

These commands can be encoded into the following Aztec Code symbol: