Hi Richard,

This a very interesting strategy and I have added it to my collection of code snippets.

On this project my approach is to try the hardware methods first since they (like ground shielding the signal line, etc.) are just good practice anyway. If that doesn't do the trick I will try some of the software solutions. I hope this method will be a way to somewhat isolate the cause of the false triggering or at least give an idea what might be going on.

This project has even forced me to get out my really old and clunky oscilloscope and get some new probes for it. Now I just have to figure out how to set it up to check for noise on the signal line. I'm a bit rusty on using the scope for diagnostics. It's been quite a while since my last class in EE.

Thanks for your thoughts,
Allan