void setup() {
  // put your setup code here, to run once:
pinMode(13, OUTPUT);
pinMode(12,OUTPUT);
pinMode(11,OUTPUT);
Serial.begin(9600);
}

void loop() {
  // put your main code here, to run repeatedly:
Serial.println("Red, STOP");
digitalWrite(13, HIGH);
digitalWrite(12, LOW);
digitalWrite(11, LOW);
delay(1000);

Serial.println("yellow, wait");
digitalWrite(13, LOW);
digitalWrite(12, HIGH);
digitalWrite(11, LOW);
delay(1000);

Serial.println("green,go");
digitalWrite(13, LOW);
digitalWrite(12, LOW);
digitalWrite(11, HIGH);
delay(1000);
}