/*
  BlinkMe2
  Turn an LED on and off once per second (improved version).
 */

// use variable ledPin to store the pin number that drives the LED
int ledPin = 13;

void setup() {                
  pinMode(ledPin, OUTPUT);      // make ledPin an output 
}

void loop() {
  digitalWrite(ledPin, HIGH);   // turn the LED on
  delay(1000);                  // wait one second
  digitalWrite(ledPin, LOW);    // turn the LED off
  delay(1000);                  // wait one second
}