Sun May 25 14:24:24 EDT 2014
Might do input capture manually from the comparator change interrupt.
Basically, read TMR0L then TMR0H
Section 11: TMR0 module:
TMR0H is updated with the contents of the high byte of Timer0
during a read of TMR0L.
So to get an update:
- read timer
- subtract previous
- shift / multiply
- add to accumulator
- store previous
Probably best to keep the timer rolling.
If the input capture is not used for anything, this can actually be
split into a top and bottom half, with top half just initiating the
capture and the bottom half performing the update.