user61969: This guide   Shows how to wire a passive buzzer to be used with tone(). I notice they have it wired to D9, which is a PWM pin. But is it required to use a PWM capable digital output pin to play tones from a passive buzzer?

user4143: No, it doesn't need to be a PWM pin. tone() uses a timer and an interrupt to generate the audio signal and can work with any IO pin.

61969: <p><a href="https://create.arduino.cc/projecthub/SURYATEJA/use-a-buzzer-module-piezo-speaker-using-arduino-uno-89df45" rel="nofollow noreferrer">This guide </a>  Shows how to wire a passive buzzer to be used with tone(). I notice they have it wired to D9, which is a PWM pin. But is it required to use a PWM capable digital output pin to play tones from a passive buzzer?</p>
 4143: <p>No, it doesn't need to be a PWM pin. <code>tone()</code> uses a timer and an interrupt to generate the audio signal and can work with any IO pin.</p>
