Using a Buzzer with Arduino

It is possible to emit sounds using a microcontroller by connecting a buzzer to one of its outputs. When you want to create a user interface, it is nice to have feedback according to the actions performed, whether it is a display, a light that lights up or changes colour, or a sound. We will see in this tutorial how to use a buzzer (or piezoelectric loudspeaker).

Hardware

• Computer
• Arduino UNO
• USB cable A Male to B Male
• Buzzer

Principle of operation

A buzzer is a kind of loudspeaker but of low power that will emit a sound according to the frequency and amplitude of vibration. It allows to play notes and to recreate simple melodies. If you want to play sounds such as music or voices, you will need to use a loudspeaker with an audio amplifier that will play an audio file stored on an SD card .

To play audio files, you can follow this tutorial.

Schematic

As a buzzer is of low power, it can be connected directly to the microcontroller on any of its output pins. In this tutorial we connect the – terminal of the buzzer to the GND and the + terminal to digital output 2.

Code

For each note there is a corresponding frequency which is stored in the pitches.h file. To play a melody, we will place the notes in a table and specify a delay between each note. We then use the tone function to apply this frequency and duration to the output of the buzzer.
To create the pitches file, click on the arrow to the right of the sketch name, then click on “create a new tab”. Then copy and paste the code with the definition of the notes.

File .ino

//Libraries
#include "pitches.h" //https://www.arduino.cc/en/Tutorial/BuiltInExamples/toneMelody

//Parameters
const int buzPin  = 2;

void setup() {
  //Init Serial USB
  Serial.begin(9600);
  Serial.println(F("Initialize System"));
}

void loop() {
  playPassed();
  delay(1000);
  playFailed();
  delay(2000);
}

void playPassed() { /* function playPassed */
  ////Play 'ON' Sound
  int melodyOn[] = {NOTE_C5, NOTE_C6, NOTE_D5, NOTE_A6};
  int durationOn = 200;
  for (int thisNote = 0; thisNote < 4; thisNote++) {
    tone(buzPin, melodyOn[thisNote], durationOn);
    delay(200);
  }
}

void playFailed() { /* function playFailed */
  ////Play 'OFF' Sound
  int melodyOff[] = {NOTE_C3, NOTE_D3};
  int durationOff = 200;
  for (int thisNote = 0; thisNote < 2; thisNote++) {
    tone(buzPin, melodyOff[thisNote], durationOff);
    delay(200);
  }
}

File pitches.h

/*************************************************

 * Public Constants

 *************************************************/

#define NOTE_B0  31
#define NOTE_C1  33
#define NOTE_CS1 35
#define NOTE_D1  37
#define NOTE_DS1 39
#define NOTE_E1  41
#define NOTE_F1  44
#define NOTE_FS1 46
#define NOTE_G1  49
#define NOTE_GS1 52
#define NOTE_A1  55
#define NOTE_AS1 58
#define NOTE_B1  62
#define NOTE_C2  65
#define NOTE_CS2 69
#define NOTE_D2  73
#define NOTE_DS2 78
#define NOTE_E2  82
#define NOTE_F2  87
#define NOTE_FS2 93
#define NOTE_G2  98
#define NOTE_GS2 104
#define NOTE_A2  110
#define NOTE_AS2 117
#define NOTE_B2  123
#define NOTE_C3  131
#define NOTE_CS3 139
#define NOTE_D3  147
#define NOTE_DS3 156
#define NOTE_E3  165
#define NOTE_F3  175
#define NOTE_FS3 185
#define NOTE_G3  196
#define NOTE_GS3 208
#define NOTE_A3  220
#define NOTE_AS3 233
#define NOTE_B3  247
#define NOTE_C4  262
#define NOTE_CS4 277
#define NOTE_D4  294
#define NOTE_DS4 311
#define NOTE_E4  330
#define NOTE_F4  349
#define NOTE_FS4 370
#define NOTE_G4  392
#define NOTE_GS4 415
#define NOTE_A4  440
#define NOTE_AS4 466
#define NOTE_B4  494
#define NOTE_C5  523
#define NOTE_CS5 554
#define NOTE_D5  587
#define NOTE_DS5 622
#define NOTE_E5  659
#define NOTE_F5  698
#define NOTE_FS5 740
#define NOTE_G5  784
#define NOTE_GS5 831
#define NOTE_A5  880
#define NOTE_AS5 932
#define NOTE_B5  988
#define NOTE_C6  1047
#define NOTE_CS6 1109
#define NOTE_D6  1175
#define NOTE_DS6 1245
#define NOTE_E6  1319
#define NOTE_F6  1397
#define NOTE_FS6 1480
#define NOTE_G6  1568
#define NOTE_GS6 1661
#define NOTE_A6  1760
#define NOTE_AS6 1865
#define NOTE_B6  1976
#define NOTE_C7  2093
#define NOTE_CS7 2217
#define NOTE_D7  2349
#define NOTE_DS7 2489
#define NOTE_E7  2637
#define NOTE_F7  2794
#define NOTE_FS7 2960
#define NOTE_G7  3136
#define NOTE_GS7 3322
#define NOTE_A7  3520
#define NOTE_AS7 3729
#define NOTE_B7  3951
#define NOTE_C8  4186
#define NOTE_CS8 4435
#define NOTE_D8  4699
#define NOTE_DS8 4978

Result

Modify notes, table size and delays to recreate the melodies you want.

Applications

• Create an interactive keyboard with sound feedback
• Create a robot that emits sounds like R2-D2

Sources

• https://www.arduino.cc/en/Tutorial/BuiltInExamples/toneMelody
• Playing WAV files with Arduino