void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
  pinMode(2, OUTPUT);
  pinMode(4, OUTPUT);
}

void loop() {
  digitalWrite(2, HIGH);
  digitalWrite(4, HIGH);
  
  // put your main code here, to run repeatedly:
  delay(10); 
  digitalWrite(2, LOW);
  digitalWrite(4, LOW);// this speeds up the simulation
}