Quote Originally Posted by matsp View Post
My guess would be that the bar-code reader generates numbers and perhaps a control code at the start and/or end.
Indeed -- the entire point of having the BCS connect to the keyboard port is for easy interfacing to software that takes its input from the keyboard. If it used some weird protocol, it would have been hooked up over serial or USB.

The times I've dealt with these things, the scanner will just return the digits followed by a carriage return.