I remember reading somewhere in avr libc docs to do e.g. this: PCIFR = _BV (some_bit) loop_until_bit_is_clear (PCIFR, some_bit);
This may be a bad example becuase of the odd write-one-to-clear semantics. That isn't the point here, I don't remember which registers this advice applied to. And I can't find it now. The only thing I could find in the datasheet that related to this was in section 13.2.4 of ATMega328P datasheet, where it says that you have to wait a cycle after assigning an output pin value before reading it back in. Are there other cases where loop_until_* or a nop is required? Thanks, Britton _______________________________________________ AVR-chat mailing list AVR-chat@nongnu.org https://lists.nongnu.org/mailman/listinfo/avr-chat