Blinking LED
by BARRAGAN <http://barraganstudio.com>

turns on and off light (LED) connected to a digital pin, with intervals of 1 second (1000 milliseconds) Note in the circuit the LED it has a positive (long leg) and a ground (short leg), if the LED doesn't turn ON, it might be it is inverted.

Created 2 December 2003
Revised 1 May 2007
 

    
// Blinking LED 
// by BARRAGAN <http://barraganstudio.com> 

int ledPin = 0;           // LED connected to the Wiring I/O board pin 0 
 
void setup() 
{ 
  pinMode(ledPin, OUTPUT); // sets the digital pin as output 
} 
 
void loop() 
{ 
  digitalWrite(ledPin, HIGH);   // sets the LED on 
  delay(1000);                  // waits for a second 
  digitalWrite(ledPin, LOW);    // sets the LED off 
  delay(1000); 
}