void setup() {
  pinMode(11,OUTPUT);// Led verde conectado al pin 11
  pinMode(7, OUTPUT);
  pinMode(3, OUTPUT);
}

void loop() {
  digitalWrite(11, HIGH);//Prende el led verde
  delay(1000);            // Espera 1 segundo
  digitalWrite(11, LOW);
  digitalWrite(7, HIGH);
  delay(1000);
  digitalWrite(7, LOW);
  digitalWrite(3, HIGH);
  delay(1000);
  digitalWrite(3, LOW);
}