#define clock_speed 16e6
#define RED_PIN 8
#define YELLOW_PIN 10
#define GREEN_PIN 12


//define the delays
int red_on = 3000, red_yellow_on = 1000, green_on = 3000, green_blink = 5000, yellow_on = 1000;

int delay_timer(int miliseconds){
  int count = 0;
  while(true){
    if(TCNT0 >= clock_speed) {
      TCNT0 = 0;
      count++;
      if(count == miliseconds) {
        count = 0;
        break;
      }
    }
  }
  return 0;
}


void setup() {
  // put your setup code here, to run once:
  // define the pins connected
  pinMode(RED_PIN, OUTPUT);
  pinMode(YELLOW_PIN, OUTPUT);
  pinMode(GREEN_PIN, OUTPUT);
  //set up timer
  TCCR0A = 0b00000000;
  TCCR0B = 0b00000101;
  TCNT0 = 0;
}

void loop() {
  // put your main code here, to run repeatedly:
  //to make red led on
  digitalWrite(RED_PIN, HIGH);
  delay_timer(red_on);
  //to make yellow led on
  digitalWrite(YELLOW_PIN, HIGH);
  delay_timer(red_yellow_on);
  //turning off red pin and yellow pin
  digitalWrite(RED_PIN, LOW);
  digitalWrite(YELLOW_PIN, LOW);
  //turning green on
  digitalWrite(GREEN_PIN, HIGH);
  delay_timer(green_on);
  //turning green off
  digitalWrite(GREEN_PIN, LOW);
  //for truning green on and off for three times
  for(int i = 0; i < 3; i++) {
    delay_timer(green_blink);
    digitalWrite(GREEN_PIN, HIGH);
    delay_timer(green_blink);
    digitalWrite(GREEN_PIN, LOW);
  }

  //for turning on yellow
  digitalWrite(YELLOW_PIN, HIGH);
  delay_timer(yellow_on);
  digitalWrite(YELLOW_PIN, LOW);
}