void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
  Serial.println("Hello, ESP32!");

  pinMode(19, OUTPUT);
  pinMode(21, OUTPUT);
}
char c;
void loop() {

  if(Serial.available() > 0){
    c = Serial.read();
    Serial.println(c);

    if(c == 'L'| c == 'l'){
      digitalWrite(19, HIGH);
       digitalWrite(21, HIGH);
    }
    else if(c == 'D'| c == 'd'){
     digitalWrite(19, LOW);
     digitalWrite(21, LOW);
    }
  delay(10); // this speeds up the simulation
} 
}