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This example is for Wiring version 0024+. If you have a previous version, use the examples included with your software. If you see any errors or have comments, please let us know.

Stretch light by Karmen Franinovic
Controls a light's intensity by pulling a stretch sensor (rubbery ruler). The stretch sensor is made of conductive rubber, that changes resistance when it is streteched. The stretch sensor is connected to analog input pin 0 The LED is connected to the analog output (PWM) pin 0

    int val;

    void setup()
    {
      // nothing for setup
    }

    void loop()
    {
      val = analogRead(0);            // read analog input pin 0
      val = (val - 400);              // min value read from the stretch sensor was 400
      val = constrain(val, 0, 1023);  // constrain value
      analogWrite(0,val);             // write value to PWM (analog) output 0
      delay(50);                      // wait 50ms for next reading
    }