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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.

Iteration over digital outputs.
Iteration with a "for" structure over output pins. LEDs are wired from pins 8 to 15

    void setup()
    {
      Serial.begin(9600);
      for (int i = 8; i < 16; i++)   // sets pins 8-15 as outputs
      {
        pinMode(i, OUTPUT);
      }
    }

    void loop()
    {
      for (int i = 8; i < 16; i++)   // sets pins 8-15 to HIGH
      {
        digitalWrite(i, HIGH);
        delay(100);  // delay to see the sequence
      }
      for (int i = 8; i < 16; i++)   // sets pins 8-15 to LOW
      {
        digitalWrite(i, LOW);
        delay(100);  // delay to see the sequence
      }
    }