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This example is for Wiring version 1.0 build 0100+. 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 an LED brightness 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 37 On Wiring v1 boards the PWM capable pins are: 29, 30, 31, 35, 36 and 37 On Wiring S board the PWM capable pins are: 4, 5, 6, 7, 19 and 20

    int sensorValue;

    void setup()
    {
      pinMode(19, OUTPUT);
    }

    void loop()
    {
      // read analog input pin 0
      sensorValue = analogRead(0);
      // min value read from the stretch sensor was 400
      // calibrare yours accordingly
      sensorValue = (sensorValue - 400);
      // constrain value in the range 0-255
      sensorValue = constrain(sensorValue, 0, 255);
      // write value to PWM (analog) output 19
      analogWrite(19, sensorValue);
      // wait 50ms for next reading
      delay(50);
    }