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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.

Potentiomenter + LED intensity by BARRAGAN
Reads values from a photoresistor connected to the analog input pin 0. The value read from the sensor is proportional to the amount of light that hits the sensor surface. The value read is used to dim a light connected to the PWM Outpin 0

    int val;

    void setup()
    {
      // nothing for setup
    }

    void loop()
    {
      val = analogRead(0);  // read analog input pin 0 (value in the range 0-1023)

      // The luminosity of the LED will be proportional to knob position.

      analogWrite(0, val);  // write the value to PWM output pin 0 (value in the range 0-1023)

      // if you want the luminosity of the LED to be inversely proportional to the amount of
      // of light in the environment comment the previous line and use the line below instead:

      //analogWrite(0, 1023-val);

      delay(100);           // wait 100ms for next reading
    }