All,

Not sure the best forum for this. We need to connect about 8 barcode scanners to a single PC application. This application needs to know all the barcode scanner inputs, and which scanner did the scan.

In this situation, each scanner is intended to direct the application in different ways. For example, scanner-A would tell the system to begin process-A, and scanner-B would tell the system to begin process-B. Sorry to be so vague, but I'm trying to get to the problem.

This being 2008, of course we are using USB scanners. They all seem to do keyboard emulation, as if 8 keyboards are plugged into the PC. This leads to 2 problems:

1) How to distinguish between each scanner's input, and
2) How to keep each scan seperate, so that 2 scans do not read in at the same time.

Problem 1 can be solved by pre-pending special characters into each scanner's scan data, so the application can know which scan came from which scanner.

Problem 2 apparently cannot be solved. Since all the scanners emulate the keyboard, there seems to be no way to prevent scanner-B from beginning a scan transmission before scanner-A has finished.

I believe the "multiple scanners using USB keyboard emulation" can be solved by not using USB devices, and using RS-232 scanners instead.

I have not seen more than 4 COM ports on a PC, but it seems XP can support up to 256 COM ports. I have 2 free PCI slots, so if I could find some cards with 4 COM ports on them, I might be able to get 8 RS-232 scanners going on the PC.

Anyone else encounter this problem? I can't be the 1st guy to hit this problem, and I can't believe I need to buy 1 PC to support 1 scanner.

Any ideas, advice welcome.