int ledr = 15;
int ledg = 2;
int ledy = 4;

void setup() {
  // put your setup code here, to run once:
  pinMode(ledr, OUTPUT);
  pinMode(ledg, OUTPUT);
  pinMode(ledy, OUTPUT);

  Serial.begin(115200);
  Serial.println("Hello, ESP32!");
}

void loop() {
  // put your main code here, to run repeatedly:

  digitalWrite(ledr, HIGH);
  delay(500);
  digitalWrite(ledr, LOW);
  delay(500);  
  digitalWrite(ledr, HIGH);
  delay(500);  
  digitalWrite(ledr, LOW);
  delay(500);

  digitalWrite(ledr, LOW);
  digitalWrite(ledg, HIGH);
  delay(2000);  
  digitalWrite(ledg, LOW);
  digitalWrite(ledy, LOW);
  
  digitalWrite(ledy, HIGH);
  delay(2000);
  digitalWrite(ledg, LOW);
  digitalWrite(ledr, LOW);
  digitalWrite(ledy, LOW);
  
  delay(2000); // this speeds up the simulation
}