Note: Pin D9 on the Arduino is not the same pin 9 on the ATmega328 IC. Pin 15 on the IC is actually the pin for Digital Pin 9 (D9) on the Arduino. If you want to see the pinout for the ATmega328 IC, ...

If your board has no printed labels, check out its pinout diagram documentation (found on the board's Arduino Store page). PWM pins in the diagram have the same tilde sign in front of the pin numbers.

Jon Bumstead has created an awesome Arduino powered 13 note midi harp after receiving ... The digital output of pins 8-11 incremented thirteen times (for the thirteen positions), and the DAC ...