Excellent point!I can see a problem if two scanners are activated at exactly the same time. The characters from each scanner might become interleaved. Perhaps it's not a problem (just re-scan), or perhaps it would be an extremely rare occurrence.
I don't know Linux well enought to know if you'll be able to attach to individual input devices rather than the generic 'keyboard' input, that would stop the issue.
If not will you have the opportunity to alter the specifications of the codes on the tickets/passes/tags/whatever that are scanned?
Whilst some codes do inclide check-sums, they are not (normally) part of the input stream. so you may want to add some strict formatting (even just leading zeros to make numeric data a fixed size) but ideally some checksum/CRC so you can detect the mixed read early, and not by a faiure in the database lookup later.
Statistics: Posted by Multiplex — Wed Apr 17, 2024 6:50 am