PWM pins work the same way across all Arduino boards, so you don't need to go out of your way to buy a Mega if you already have a board supporting PWM. On the Uno, Nano, and Mini, the PWM pins are ...

Since the interrupt signal comes from outside the Arduino it is called as external interrupt. Arduino Uno R3 has two external interrupts: int.0 (pin 2) and int.1 (pin 3). While connecting a RT to ...