dhenry:
The timer interrupt is slow (1s) to service a temperature control loop, and the external is a once-around pulse on a slow running motor (~3.5Hz).
I need to turn off the temperature control loop from time to time to act on some motor events.
And I'll ultimately need to turn of the external motor interrupt when I add a faster timer interrupt (say 125us) to sample some data.That makes zero sense.
There must be a slick way to turn interrupts on and off individually with minimal avr register writes. Or something.
Yes, there is - all outlined in the datasheet.
hmmm... Seems perfectly clear to me. Let me try again.
-Temperature control loop interrupt fires every second.
-Motor control loop interrupt fires ~3 times per second
-My sample clock wants to be 125us which I think will be another timer interrupt (I'll write that part tomorrow).
Sometimes, depending on what is happening in the main loop, I want to respond to a motor interrupt by starting to sample an analog signal.
When that happens, I don't want the slower, relatively less critical ISRs to cause me to miss the faster critical timing interrupts, so I'd turn off only the ones I want to ignore, then turn them back on when I care less.