[jeff5may]

I'm still working on this sketch, and most of it actually works! It has an LCD driven menu where you will be able to set functions, modes, etc. When not in the menu, it will display the current mode and status. I left serial pins open on D0, D1 to communicate that way.

As far as comms go with the arduino, you can hook up just about anything to a dev board as long as you use the right pins. With the smaller boards, creativity and luck is needed to make it do what you want. For me, this is part of the appeal of this project. Sure, I could go buy something elaborate and do it easy. But what fun is that? I'm not at work!

As far as safety is concerned, I would never completely trust an embedded device for anything critical. The rig you put this in should have its own fail-safe built into it as a cardinal rule. If it absolutely must work or else, you should probably go get something that has passed multiple testing methods and has a diploma already. This one might not solve all of your problems, and may end up causing new problems instead.