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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.

Phototransistor: Fairchild GRB1134 by BARRAGAN http://barraganstudio.com
Reads values from a phototransistor connected to the analog input pin 0. The value read from the sensor is proportional to the amount of light that hits the sensor's surface. The value read is printed to the serial monitor

    int sensorValue;

    void setup()
    {
      Serial.begin(9600);  // sets the serial port to 9600
    }

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