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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.

Switch by BARRAGAN http://barraganstudio.com
Use a switch connected to digital pin 8. Digital pin 8 is used as input and connected to a switch When the switch is pressed, the Wiring board LED turn ON, the LED turns OFF when the switch is released. For the Wiring boards v1 the on-board LED is on pin 48, on Wiring S the on-board LED is on pin 15.

    int switchPin = 8;  // digital pin to attach the switch

    void setup()
    {
      pinMode(switchPin, INPUT);  // set digital pin 0 as input
      pinMode(WLED, OUTPUT);  // set digital (Wiring on-board LED) as output
    }

    void loop()
    {
      if (digitalRead(switchPin) == HIGH) // if the switch is pressed
      {
        digitalWrite(WLED, HIGH);         // turns the Wiring LED ON
      }
      else                                // if the switch is not pressed
      {
        digitalWrite(WLED, LOW);          // turns the Wiring LED OFF
      }
    }