I copied the sketch to another computer's hard drive and when I upload it from that computer the sketch functions properly. So, it has something to do with the 1st computer. This is in the impossible region. It makes no sense. I have tested this back and forth many times and the failure is consistent. It never works full function when uploaded from the hard drive from computer 1, only when it is uploaded from a flash drive plugged into computer 1. With computer 2 it does not make any difference. With computer 2 it works as it should regardless of where it is uploaded from. The only thing that doesn't work when it is uploaded from the hard drive on computer 1 is the 3x4 keyboard scanning. I thought that perhaps computer 1 might be introducing some noise on the usb line but disconnecting it does not correct the problem. This problem was causing me to chase my tail for days until I stumbled on the solution.