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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.

Increment Decrement. by BARRAGAN http://barraganstudio.com
Writing "a++" is equivalent to "a = a + 1". Writing "a--" is equivalent to "a = a - 1".

    int current = 8;  // variable the keeps which light must be turn on next

    void setup()
    {
      for (int i = 8; i < 16; i++)   // set pins 8-15 as outputs
      {
        pinMode(i, OUTPUT);
      }
    }

    void loop()
    {
      turn_all_off();  // turns all LEDs off
      digitalWrite(current, HIGH);  // set the current light ON
      delay(200);  // wait for 200ms
      current++;  // increment current LED
      if (current > 15)   // range check, if last LED goes back to LED 8
      {
        current = 8;
      }
    }

    void turn_all_off()    // function to turn off all the LEDs
    {
      for (int i = 8; i < 16; i++)   // connected to digital pins 8-15
      {
        digitalWrite(i, LOW);
      }
    }