UCLA BMES Build Team

Workshop 3 - ESP32 Analog

Activity 1 - Piezo Buzzer

Task:

• Make a theremin (musical instrument) using a photoresistor and piezo buzzer
  • Alternatively, use a potentiometer to control pitch
• Play a scale
• Relevant functions

  tone(pin, frequency);
  tone(pin, frequency, duration);
  noTone(pin);
  

• Revelant components
  • Piezo Buzzer:
  • Photoresistor: Can be wired in both directions, since it isn’t a diode.
  • Potentiometer: Can also be wired in both directions either place power at the left or right most pin.

Circuit:

Code:

int piezo = 3; // Pin for piezo buzzer
int photo = 5; // Pin for photoresistor

void setup()
{
  pinMode(piezo,OUTPUT);
}

void loop()
{
  int value = analogRead(photo); // Analog input
  int note = map(value,0,1023,400,1000); // Map to output values
  tone(piezo,note); // Play tone on buzzer
}

UCLA BMES Build Team