touch
?attachInterrupt(pin, ISR, mode);
/* pin: the pin number
ISR: the ISR to call when the interrupt occurs
mode: defines when the interrupt should be triggered.
mode LOW to trigger the interrupt whenever the pin is low,
mode CHANGE to trigger the interrupt whenever the pin changes value
mode RISING to trigger when the pin goes from low to high,
mode FALLING for when the pin goes from high to low. */