Blink LED

//Blinking LED

const int LED = 13; // LED connected to
                   //  digital pin 13

void setup()
{
  pinMode(LED, OUTPUT);   // sets the digital
                         // pin as output  
}

void loop()
{
  digitalWrite(LED, HIGH);    //turns on the LED on
  delay(1000);               // waits for a second
  digitalWrite(LED, LOW);   // turns the LED off
  delay(1000);             // waits for a second
}