Introduction: Traffic Light ,9 Led Using Arduino Uno

Materials required:

1. 3 red led, 3 yellow led, 3 green led

2. Breadboard

3. Arduino UNO

4. Cable

5. Arduino IDE on PC

6. Connecting wires

Summary of project:

This project is making a simple traffic light but helps in understanding Arduino basics. Basically there are 3 traffic lights with 9 leds that light up according to turn. In this project you will learn:

  • Using digital output pins
  • Using the Arduino IDE
  • Uploading code on the Arduino
  • and most important of all make a project yourself

Step 1: Step 2 :Make Connections

  1. Connect the red, yelow, green,red, yelow, green, red, yelow, green leds to pins 2,3,4,5,6,7,8,9,10 of Arduino respectively . (connect longer ends of the led)
  2. Connect the shorter side of the led to ground and the longer side to the output pins and then connect it to the GND pin on the Arduino
  3. Connect the Arduino to the PC and download the software if not present already (from www.ardunio.cc)
  4. Open the arduino programmer go to tools> board and select "Arduino Uno"
  5. Next go to tools> serial port and select appropriate port to which Arduino is connected
  6. Next click file>new and paste the code below

//CODE BY OMAR ADIL

int led2 = 2;

int led3 = 3;

int del=1000;

int led4 = 4;

int led5 = 5;

int led6 = 6;

int led7 = 7;

//CODE BY OMAR ADIL

int led8 = 8;

int led9 = 9;

int led10 =10;

// the setup routine runs once when you press reset:

void setup() {

// initialize the digital pin as an output.

pinMode(led2, OUTPUT);

pinMode(led3, OUTPUT);

pinMode(led4, OUTPUT);

pinMode(led5, OUTPUT);

pinMode(led6, OUTPUT);

pinMode(led7, OUTPUT);

pinMode(led8, OUTPUT);

pinMode(led9, OUTPUT);

pinMode(led10, OUTPUT);

}

// the loop routine runs over and over again forever:

void loop() {

digitalWrite(led2, HIGH);

digitalWrite(led3, LOW);

digitalWrite(led4, LOW);

digitalWrite(led5, HIGH);

digitalWrite(led6, LOW);

digitalWrite(led7, LOW);

digitalWrite(led8, HIGH);

digitalWrite(led9, LOW);

digitalWrite(led10, LOW);

delay(del/2);

//ALL RED

digitalWrite(led2, LOW);

digitalWrite(led3, LOW);

digitalWrite(led4, HIGH);

digitalWrite(led5, HIGH);

digitalWrite(led6, LOW);

digitalWrite(led7, LOW);

digitalWrite(led8, HIGH);

digitalWrite(led9, LOW);

digitalWrite(led10, LOW);

delay(2*del);

//GREEN1

digitalWrite(led2, LOW);

digitalWrite(led3, HIGH);

digitalWrite(led4, LOW);

digitalWrite(led5, HIGH);

digitalWrite(led6, LOW);

digitalWrite(led7, LOW);

digitalWrite(led8, HIGH);

digitalWrite(led9, LOW);

digitalWrite(led10, LOW);

delay(del);

//YELLOW1

digitalWrite(led2, HIGH);

digitalWrite(led3, LOW);

digitalWrite(led4, LOW);

digitalWrite(led5, HIGH);

digitalWrite(led6, LOW);

digitalWrite(led7, LOW);

digitalWrite(led8, HIGH);

digitalWrite(led9, LOW);

digitalWrite(led10, LOW);

delay(del/2);

//ALL RED

digitalWrite(led2, HIGH);

digitalWrite(led3, LOW);

digitalWrite(led4, LOW);

digitalWrite(led5, LOW);

digitalWrite(led6, LOW);

digitalWrite(led7, HIGH);

digitalWrite(led8, HIGH);

digitalWrite(led9, LOW);

digitalWrite(led10, LOW);

delay(del*2);

//GREEN2

digitalWrite(led2, HIGH);

digitalWrite(led3, LOW);

digitalWrite(led4, LOW);

digitalWrite(led5, LOW);

digitalWrite(led6, HIGH);

digitalWrite(led7, LOW);

digitalWrite(led8, HIGH);

digitalWrite(led9, LOW);

digitalWrite(led10, LOW);

delay(del);

//YELLOW2

digitalWrite(led2, HIGH);

digitalWrite(led3, LOW);

digitalWrite(led4, LOW);

digitalWrite(led5, HIGH);

digitalWrite(led6, LOW);

digitalWrite(led7, LOW);

digitalWrite(led8, HIGH);

digitalWrite(led9, LOW);

digitalWrite(led10, LOW);

delay(del/2);

//ALL RED

digitalWrite(led2, HIGH);

digitalWrite(led3, LOW);

digitalWrite(led4, LOW);

digitalWrite(led5, HIGH);

digitalWrite(led6, LOW);

digitalWrite(led7, LOW);

digitalWrite(led8, LOW);

digitalWrite(led9, LOW);

digitalWrite(led10, HIGH);

delay(del*2);

//GREEN 3

digitalWrite(led2, HIGH);

digitalWrite(led3, LOW);

digitalWrite(led4, LOW);

digitalWrite(led5, HIGH);

digitalWrite(led6, LOW);

digitalWrite(led7, LOW);

digitalWrite(led8, LOW);

digitalWrite(led9, HIGH);

digitalWrite(led10, LOW);

delay(del);

//YELLOW3

}