@Edwin: Thank you very much, that's a great deal of information you gave, that's definitely worth being considered.
> Polling for state-change is never a good idea (you might miss stuff if > your cpu is busy doing something else) > This is why interrupts where invented I think. You are right, it's neither very elegant nor efficient to poll input signals, it's much more a quick and dirty hack, that I prefer at the beginning of my project, as I do not want to elaborate on hardware interfacing too much right now. But I guess, your solution will be the right way to go at a later time. I was working on a Tiny Tiger system that seems to be polling it's input pins (timer interrupt driven) periodically (it's done in a proprietary device driver) and the results were quite satisfying in my opinion, so I guessed, it could be a good enough solution to do it in a similar manner on a fox board (which is much more powerful I think). --------------------------------------------------------------------- Anyway, I still wonder what might be the problem installing the timer1 interrupt. The interrupt (3) is not used on my system but enabling it keeps hanging my system. I even disabled the serial driver in the kernel, but that did not correct the problem. Any further ideas? Kind regards Dietmar Dreyer
