Matchbox Speaker

Description:
In this lab I created a instrument that, when the matchbox slid back and forth, the sound of the piezzo speaker would warp.  The matchbox basically serveda as a sensor tool, letting the light come into the matchbox and therefore the sensor reads different frequencies. 
Materials:
Arduino
Breadboard
Wires
Piezzo speaker
Matchbox
Resistors
Code:
 

/* Theremin

 * --------

 *

 *

 * Created 24 October 2006

 * copyleft 2006 Tod E. Kurt <tod@todbot.com

 * http://todbot.com/

 */

int potPin = 0;    // select the input pin for the potentiometer

int speakerPin = 7;

int val = 0;

void setup() {

  pinMode(speakerPin, OUTPUT); 

  Serial.begin(9600);

  Serial.println("ready");

}

void loop() {

  digitalWrite(speakerPin, LOW);

  val = analogRead(potPin);    // read value from the sensor

  val = val*2;                 // process the value a little

  //val = val/2;                 // process the value a little

  for( int i=0; i<50; i++ ) {  // play it for 50 cycles

    digitalWrite(speakerPin, HIGH);

    delayMicroseconds(val);

    digitalWrite(speakerPin, LOW);

    delayMicroseconds(val);

  }

}