const int red=15;
const int green=16;
const int blue=18;

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

void loop() {

  digitalWrite(red,HIGH);
  digitalWrite(green,LOW);
  digitalWrite(blue,LOW);
  delay(500);


  digitalWrite(red,LOW);
  digitalWrite(green,HIGH);
  digitalWrite(blue,LOW);
  delay(500);


  digitalWrite(red,LOW);
  digitalWrite(green,LOW);
  digitalWrite(blue,HIGH);
  delay(500);
}