Interrupt limitations?

[Andrew]

Originally Posted by randomperson

hmm... this just kind of occured to me..

Ok, yes we can now find exactly when something is happening by being interrupted... but we still cant send out data more than every 17ms (or 25 for the edubot). ill post it nonetheless... any thoughts on this?

Some of the inputs (digital and analog) can be read directly and some of the outputs (definitely digital and I think PWM) can be written directly without going through the communication to the master uP. You'll have to dig through the default code to find which ones allow this.

If you plug through the timer code that IFI put together (http://www.innovationfirst.com/FIRST...ite_papers.htm), you will find out how to output a digital out every n millisec. I've run those mods (with some additional mods of my own, of course) and 'scoped out a 10 msec sample time. It was very reliable (ie no periodic glitches due to overflow or other stuff interrupting the low priority interrupt).