Arduino Traffic Light

In this project I created a traffic light prototype with an Arduino UNO. The LEDs would have to light up at the sequence of a real traffic light and work in a constant loop. Materials used in the project:

• Arduino UNO
• breadboard
• 5mm LED
• 220 ohm resistors
• wires

I used the Arduino programming software to create the code for the traffic light.

#define RED_PIN 5      // defining the constants
#define YELLOW_PIN 4
#define GREEN_PIN 3

void setup() {        // binding them to outputs
  pinMode(RED_PIN, OUTPUT);
  pinMode(YELLOW_PIN, OUTPUT);
  pinMode(GREEN_PIN, OUTPUT);
}

void loop() {          //main loop
  digitalWrite(RED_PIN, HIGH);   
  delay(2000);                       
  digitalWrite(YELLOW_PIN, HIGH);
  delay(1000);
  digitalWrite(YELLOW_PIN, LOW);
  digitalWrite(RED_PIN, LOW);
  digitalWrite(GREEN_PIN, HIGH);
  delay(2500);
  digitalWrite(GREEN_PIN, LOW);
}