Metrologic Optimus R, Programming Manual

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Chapter 3 Terminal Specific Function Library 39
3.2 Barcode Reader
The barcode decoding routines consist of 3 functions:
InitScanner1() : to initialize the scanner port.
Decode() : to perform decoding.
HaltScanner1() : to stop the scanner port from operating.
3.2.1 Barcode Decoding
To enable barcode decoding capability in the system, the first thing is that the scanner port
must be initialized by calling the
InitScanner1() function. After the scanner port is
initialized, the Decode() function can be called in the program loops to perform barcode
decoding.
Below are four global variables related to the barcode decoding routines. These variables
are declared by the system, and therefore, the user program needs not to declare them.
extern unsigned char
ScannerDesTbl[23];
This unsigned character array governs the operation of the Decode() routine.
extern char CodeBuf[];
This buffer contains the decoded data after successful decoding.
extern char
CodeType;
This character indicates the type of code (symbology) being decoded after successful
decoding.
extern int CodeLen;
This integer indicates the length of the decoded data after successful decoding.