//define
int red = 18;
int yellow = 19;
int green = 21;


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

  pinMode(red, OUTPUT);
  pinMode(yellow, OUTPUT);
  pinMode(green, OUTPUT);

}

void loop() {
  // put your main code here, to run repeatedly:
  delay(1000); // this speeds up the simulation
  digitalWrite(red, HIGH);
  delay(1000);
  digitalWrite(red, LOW);
  delay(1000); // this speeds up the simulation
  digitalWrite(yellow, HIGH);
  delay(1000);
  digitalWrite(yellow, LOW);
  delay(1000); // this speeds up the simulation
  digitalWrite(green, HIGH);
  delay(1000);
  digitalWrite(green, LOW);
}