Light Theremin

Arduino Project Book #6: Light Theremin

Parts required:

•  Photoresistor

•  10 kilohm resistor

•   Small speaker connected to Pin 8 and ground

 //Arduino Book Project #6 - Light Theremin

int sensorValue; // variable to hold sensor value

int sensorLow = 1023; // variable to calibrate low value

int sensorHigh = 0; // variable to calibrate high value

const int ledPin = 13; // LED pin

void setup() {

 // Make the LED pin an output and turn it on

 pinMode(ledPin, OUTPUT);

 digitalWrite(ledPin, HIGH);

 // calibrate for the first five seconds after program runs

 while (millis() < 5000) {

   sensorValue = analogRead(A0);    // record the maximum sensor value

   if (sensorValue > sensorHigh) {

       sensorHigh = sensorValue;

   }

   if (sensorValue < sensorLow) {    // record the minimum sensor value

     sensorLow = sensorValue;

   }

 }

 digitalWrite(ledPin, LOW);  // turn the LED off, signaling the end of the calibration period

}

void loop() {

 sensorValue = analogRead(A0);  //read the input from A0 and store it in a variable

 // map the sensor values to a wide range of pitches

 int pitch = map(sensorValue, sensorLow, sensorHigh, 50, 4000);

 tone(8, pitch, 20);  // play the tone for 20 ms on pin 8

 delay(10);  // wait for a moment

}