twoledblink.ino

void setup()
{
    //pin 2 and 13 as output
    //comments
    pinMode(2,OUTPUT);
    pinMode(13,OUTPUT);
}

void loop()
{
    //LED2ON
    digitalWrite(2,HIGH);
    //LED13OFF
    digitalWrite(13,LOW);
    //pause
    delay(1000);

    //LED2ON
    digitalWrite(2,LOW);
    //LED13OFF
    digitalWrite(13,HIGH);
    //pause
    delay(1000);
}