Once you have your code changed to use millis() instead of delay() to detect long and short presses it should be trivial to have it detect very-long(30 second) presses. No need for interrupts once you get rid of delay().
Once you have your code changed to use millis() instead of delay() to detect long and short presses it should be trivial to have it detect very-long(30 second) presses. No need for interrupts once you get rid of delay().