void setup() {
  // put your setup code here, to run once:
   Serial.begin(115200);
   pinMode(19, OUTPUT);
   pinMode(18, OUTPUT);
   pinMode(5, OUTPUT);
} 

void loop() {
   // put your main code here, to run repeatedly:
   digitalWrite(19, HIGH);
   delay(500);
   digitalWrite(19, LOW);
   delay(500); // this speeds up the simulation
   digitalWrite(18, HIGH);
   delay(500);
   digitalWrite(18, LOW);
   delay(500); // this speeds up the simulation
   digitalWrite(5, HIGH);
   delay(500);
   digitalWrite(5, LOW);
   delay(500); // thos speeds up the simulation
   digitalWrite(18, HIGH);
   delay(500);
   digitalWrite(18, LOW);
   digitalWrite(19, HIGH);
   delay(500);
   digitalWrite(19, LOW);


}