// Black - ground wire
// Red - Power supply wire
// short leg on LED is cathode and should be connected to the ground

//Define LEDs
const int red = 12;
const int yellow = 11;
const int green = 10;
const int Pot = 2;
// define time delays
int redtime = 3000;
int yellowtime = 1000;
int greentime = 3000;

void setup() {
  // put your setup code here, to run once:
  pinMode(red, OUTPUT);
  pinMode(yellow, OUTPUT);
  pinMode(green, OUTPUT);
  pinMode(Pot, INPUT);

  //must initialise pins all as off initally
  initialise_pins();
}

void loop() {
  // put your main code here, to run repeatedly:
  if (digitalRead(Pot) == HIGH){
    traffic_light();
  }

}








// function to initialise pins
void initialise_pins(){
  digitalWrite(green, LOW);
  digitalWrite(yellow, LOW);
  digitalWrite(red, LOW);
}

// function for traffic lights
void traffic_light(){
  digitalWrite(red, HIGH);
  delay(redtime);
  digitalWrite(red, LOW);
  digitalWrite(green, HIGH);
  delay(greentime);
  digitalWrite(green, LOW);
  digitalWrite(yellow, HIGH);
  delay(yellowtime);
  digitalWrite(yellow, LOW);
}