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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.

Photoresistor by BARRAGAN http://barraganstudio.com
Reads values from a photoresistor connected to analog input pin 0 (or A0) and prints the result to the serial monitor The value read from the sensor is proportional to the amount of light that hits the sensor's surface.

    int sensorValue;

    void setup()
    {
      Serial.begin(9600);      // starts the serial port at 9600
    }

    void loop()
    {
      sensorValue = analogRead(0);     // read analog input pin 0
      Serial.print(sensorValue, DEC);  // prints the value read
      Serial.print(" ");               // prints a space between the numbers
      delay(100);                      // wait 100ms for next reading
    }