AVR-Chat

Hi Erik,

> Who ever came up with this orignally was a frickin' genius.
> Sure, it's for PIC but the code is in C.
> A little helpful cut-n-paste to give you the basic idea.
>
> ;static unsigned clock_A,clock_B,debounced_state;
> ;unsigned debounce(unsigned new_sample)
> ;{
> ;  unsigned delta;
> ;  unsigned changes;
> ;
> ;  delta = new_sample ^ debounced_state;   //Find all of the changes
> ;
> ;  clock_A ^= clock_B;        //Increment the counters
> ;  clock_B  = ~clock_B;
> ;
> ;  clock_A &= delta;          //Reset the counters if no changes
> ;  clock_B &= delta;          //were detected.
> ;
> ;  changes = ~(~delta | clock_A | clock_B);
> ;  debounced_state ^= changes;
> ;
> ;  return changes;
> ;} /* debounce */
> ;
>
> The cool thing is that this can debounce a whole port at once.  It
> runs in an interrupt routine.

Thanks. I've got a single button debounce by now, but this one is 
quite nice due to its multi-input nature. I've saved it to my favs for 
future reference.

Best,
Marc