HP-41 Barcode Scanner and Generator

[gomi42]

Hi Paul,

thx for the good news.

Your good "beep" is really strange. The barcodes are protected by a checksum per row, so they should be safe. But... The checksum used is quite simple and not very safe when it is about multiple errors in a row. Single errors are handled perfectly. That means if more than one bar is wrongly read the checksum can still be correct. Nowadays there are better algorithms known (e.g. CRC, ...).

I don't hope that the printed barcodes are at a boundary of the specification (which might challenge the wand). I think especially of the minimum width of the narrow bars.

Michael