// This is a simple traffic light project that uses four diodes
// (red, yellow, green and the green arrow).
// Time intervals between states are generated using the Delay() function
// The serial monitor shows textually which lights are ON.
// Since this is a simple project, the delay() function is used. 
// The next project will do the same without using the delay() function.
// 


void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);
  pinMode(8, OUTPUT);     // red light
  pinMode(9, OUTPUT);     // yellow light
  pinMode(10, OUTPUT);    // green light
  pinMode(11, OUTPUT);    // green arrow

}

void loop() {
  // put your main code here, to run repeatedly:
  digitalWrite(8, HIGH);    // red light ON
  digitalWrite(11, HIGH);   // green arrow ON
  Serial.println("Red and green arrow are ON");
  delay(5000);
  digitalWrite(9, HIGH);    // yellow light ON
  Serial.println("Red, yellow and green arrow are ON");
  delay(2000);
  digitalWrite(9, LOW);     // yellow light OFF
  digitalWrite(8, LOW);     // red light OFF
  digitalWrite(11, LOW);    // green arrow OFF
  digitalWrite(10, HIGH);   // green light ON
  Serial.println("Green is ON");
  delay(5000);
  digitalWrite(10, LOW);    // green light OFF
  delay(400);
  Serial.println("Green blinks");
  digitalWrite(10, HIGH);   // green blink
  delay(400);
  digitalWrite(10, LOW);
  delay(400);
  digitalWrite(10, HIGH);
  delay(400);
  digitalWrite(10, LOW);
  // delay(400);
  digitalWrite(9, HIGH);    // yellow light ON
  Serial.println("Yellow is ON");
  delay(2000);
  digitalWrite(9, LOW);     // yellow light OFF

}