[miketwalker]

I think this is a very interesting project, but I have to wonder why you want to use a TI-83/84 so badly? Why not simply use another made-to-integrate controller that can do calculations like you wish (such as trajectory as somebody asked before)? I think using an off-the-shelf component like that would greatly reduce the risk of problems in an event (if it breaks, replace it quickly) and you could also pass the code on open-source to teams that could easily work with and setup the hardware end of it. I do find it to be an interesting project, and definitely very respectable if you're able to pull it off... I just wonder if it is where you should focus your efforts. Either way, good luck.