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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.

Loop by BREVIG http://alexanderbrevig.com inspired by Capt.Tagon
Create an array of LED instances and play Knight Rider with them.

    #include <LED.h>

    const byte TIMER = 100;        //each LED will stay in for TIMER ms
    const byte NUMBER_OF_LEDS = 5;

    //create array of LED instances, wire LEDs from pin 8 to 12 (to ground through a resistor).
    LED led[NUMBER_OF_LEDS] = {
      LED(8), LED(9), LED(10), LED(11), LED(12)
    };

    void setup(){/*no setup required*/}

    void loop()
    {
      byte currentLED = 0; //keep track of current LED to blink

      for (currentLED = 0; currentLED < NUMBER_OF_LEDS; currentLED++)
      { //loop up
        led[currentLED].on();
        delay(TIMER);
        led[currentLED].off();
      }
      for (currentLED = NUMBER_OF_LEDS-1; currentLED >= 0; currentLED--)
      { //loop down
        led[currentLED].on();
        delay(TIMER);
        led[currentLED].off();
      }
    }