Play a Tone on a Buzzer

Part of the Outputs section of Coddy's Arduino journey. Lesson 10 of 24.

A buzzer clicks every time the voltage on its pin changes. Click it hundreds of times a second and you hear a note.

The number of times per second is the frequency, counted in hertz (Hz). A higher frequency is a higher note: 440 Hz is the note A, and 880 Hz is the A one octave above it.

tone(pin, frequency) switches the pin on and off at that frequency for you:

tone(8, 440);  // play 440 Hz on pin 8

Like a PWM pin, the tone keeps playing on its own, through delay(), until you call tone() again with another frequency. It works on any pin, not only the ~ ones.

Challenge

Easy

The buzzer is on pin 8. Make a two-note siren:

play 440 Hz for one second
then 880 Hz for one second
again and again

Press Run and listen, then Check.

Try it yourself

const int buzzerPin = 8;

void setup() {
}

void loop() {
  // 440 Hz for a second, then 880 Hz for a second
}

Test yourself

This lesson includes a short quiz. Start the lesson to answer it and track your progress.

All lessons in Outputs

Practice on your own: Arduino playground