Simple piezo piano using Arduino

It’s time to make some noise, ok musicians friends who have an Arduino board and some time to spend, I’ll show you how to build a very simple piano using a piezo for playing sound.

Our piano is gonna have the basec 8 notes : ‘c’  , ‘d’,  ‘e’,  ‘f’,  ‘g’, ‘a’,  ‘b’,  ‘C’ so that’s what we need to create this :

– Arduino board

– Piezo (for sound output)

– 8 buttons (one for every note)

– 8 Resistors (for the buttons)

– 10 Cables

The circuit connectivity :

As you see there are 8 buttons / notes in a row for  ‘c’  , ‘d’,  ‘e’,  ‘f’,  ‘g’, ‘a’,  ‘b’,  ‘C’ and when you press one you gonna hear the sound (within frequency creation) from the piezo.

The Arduino code is really simple, it just reads the signals from the buttons and it creates a frequency to produce sound with the piezo.

The code follows bellow :

int button_C = 2;
int button_D = 3;
int button_E = 4;
int button_F = 5;
int button_G = 6;
int button_A = 7;
int button_B = 8;
int button_Cup = 9;

int speaker = 13;

int buttonstate_C = 0;
int buttonstate_D = 0;
int buttonstate_E = 0;
int buttonstate_F = 0;
int buttonstate_G = 0;
int buttonstate_A = 0;
int buttonstate_B = 0;
int buttonstate_Cup = 0;

//NOTES         'c'  , 'd',  'e',  'f',  'g', 'a',  'b',  'C'
int tones[] = { 1915, 1700, 1519, 1432, 1275, 1136, 1014, 956 }; //freq
int Cur_tone = 0;

void setup()
{
  pinMode(button_C, INPUT);
  pinMode(button_D, INPUT);
  pinMode(button_E, INPUT);
  pinMode(button_F, INPUT);
  pinMode(button_G, INPUT);
  pinMode(button_A, INPUT);
  pinMode(button_B, INPUT);
  pinMode(button_Cup, INPUT);

  pinMode(speaker, OUTPUT);
}

void loop()
{
	buttonstate_C = digitalRead(button_C);
	buttonstate_D = digitalRead(button_D);
	buttonstate_E = digitalRead(button_E);
	buttonstate_F = digitalRead(button_F);
	buttonstate_G = digitalRead(button_G);
	buttonstate_A = digitalRead(button_A);
	buttonstate_B = digitalRead(button_B);
	buttonstate_Cup = digitalRead(button_Cup);

	if((buttonstate_C == HIGH) || (buttonstate_E == HIGH) || 
		(buttonstate_G == HIGH) || (buttonstate_D == HIGH) || 
		(buttonstate_F == HIGH) || (buttonstate_A == HIGH) || 
		(buttonstate_B == HIGH) || (buttonstate_Cup == HIGH) )
	{ 
		if (buttonstate_C == HIGH)
		{
			Cur_tone = tones[0];
		} 
		if (buttonstate_E == HIGH)
		{
			Cur_tone = tones[1];
		}
		if (buttonstate_G == HIGH)
		{
			Cur_tone = tones[2];
		}
		if (buttonstate_D == HIGH)
		{
			Cur_tone = tones[3];
		}
		if (buttonstate_F == HIGH)
		{
			Cur_tone = tones[4];
		}
		if (buttonstate_A == HIGH)
		{
			Cur_tone = tones[5];
		}
		if (buttonstate_B == HIGH)
		{
			Cur_tone = tones[6];
		}
		if (buttonstate_Cup == HIGH)
		{
			Cur_tone = tones[7];
		}

		digitalWrite(speaker, HIGH);
		delayMicroseconds(Cur_tone);
		digitalWrite(speaker, LOW);
		delayMicroseconds(Cur_tone);
	}
	else //in case no button is pressed , close the piezo
	{
		digitalWrite(speaker, LOW);
	}

}

As you see the frequencies for the notes are :

1915, 1700, 1519, 1432, 1275, 1136, 1014, 956

when you write this value of electricity into a piezo it produces those notes.