int RED=26;
int YELLOW=26;
int GREEN=26;

void setup(){
  Serial.begin(115200);
  Serial.println("Stop,ESP32");
 pinMode(RED,OUTPUT);  
 Serial. println("Ready,ESP32");
 pinMode(YELLOW, OUTPUT);
 Serial.println("Go,ESP32");
 pinMode(GREEN, OUTPUT);
}
void loop(){
  digitalWrite(RED, HIGH);
  Serial.println("ON");
  delay(100);
  digitalWrite(RED, LOW);
  Serial.println("OFF");
  delay(100);
  digitalWrite(YELLOW, HIGH);
  Serial.println("ON");
  delay(100);
  digitalWrite(YELLOW, LOW);
  Serial.println("OFF");
  delay(100);
  digitalWrite(GREEN, HIGH);
  Serial.println("ON");
  delay(100);
  digitalWrite(GREEN, LOW);
  Serial.println("OFF");
  delay(100);
}