Input digital pins are readable as high or low. Most pins generate pin-change interrupts in blocks. A block is a set of pins associated with the same interrupt: NOTE: The name "PCINT" is used for both ...

See PCINT pin table at the bottom for more details. Arduino Uno/Nano/Mini: All pins are usable Arduino Mega: 10, 11, 12, 13, 50, 51, 52, 53, A8 (62), A9 (63), A10 (64 ...