Buzzer Piano: Keys & Note Frequencies

Why it’s here

Combine discrete inputs with a buzzer output.

How it works

Each virtual key selects one frequency. The displayed sketch is the minimal example for a single physical key; a full hardware keyboard needs separate input pins and a scanner.

Try it

1. Open this experiment
2. Enable sound and run. Play C, E and G separately, comparing the frequencies in the monitor with the notes you hear.

Connections

• D2…D7, D12 — Illustrative keyboard inputs
• D8 — Buzzer output example

Example sketch

void setup() {
  pinMode(2, INPUT_PULLUP);
  pinMode(8, OUTPUT);
}

void loop() {
  if (digitalRead(2) == LOW) {
    tone(8, 262);
  } else {
    noTone(8);
  }
}

Check your understanding

Does the included sketch implement the whole virtual keyboard?