The question is not clear. It works the way it is designed; and such designs can be different. This is not a camera, and you don't have to do image recognition. :-)
For further information, please see:
http://en.wikipedia.org/wiki/Barcode_reader[
^].
If you really need to do "barcode programming" (what is that? :-)), you will also need to read the manufacturer's documentation. :-)
—SA
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