In this project, we are looking for the case of four traffic lights. The traffic light system which we have designed here is working on the basis or Arduino Uno, a microcontroller which we could program according to our needs.

The software we use here is  Arduino IDE, which is an open-source programing software, where we could type the programming according to our needs. The program for the above traffic light circuit is,

 void setup() {

  // configure the output pins

  pinMode(0,OUTPUT); 

  pinMode(1,OUTPUT);

  pinMode(2,OUTPUT);

  pinMode(3,OUTPUT);

  pinMode(4,OUTPUT);

  pinMode(5,OUTPUT);

  pinMode(6,OUTPUT);

  pinMode(7,OUTPUT);

  pinMode(8,OUTPUT);

  pinMode(9,OUTPUT);

  pinMode(10,OUTPUT);

  pinMode(11,OUTPUT); 

}

 

void loop() 

{

  digitalWrite(0,0); //enables the 1st set of signals

  digitalWrite(1,0);

  digitalWrite(2,1);

  digitalWrite(3,0);

  digitalWrite(4,0);  

  digitalWrite(5,1);

  digitalWrite(6,0);

  digitalWrite(7,0);

  digitalWrite(8,1);

  digitalWrite(9,1);

  digitalWrite(10,0);

  digitalWrite(11,0);

  delay(5000);

 

  digitalWrite(0,0); //yellow 1

  digitalWrite(1,0);

  digitalWrite(2,1);

  digitalWrite(3,0);

  digitalWrite(4,0);  

  digitalWrite(5,1);

  digitalWrite(6,0);

  digitalWrite(7,0);

  digitalWrite(8,1);

  digitalWrite(9,0);

  digitalWrite(10,1);

  digitalWrite(11,0);

  delay(3000);

 

  digitalWrite(0,0); //enables the 2st set of signals

  digitalWrite(1,0);

  digitalWrite(2,1);

  digitalWrite(3,0);

  digitalWrite(4,0);  

  digitalWrite(5,1);

  digitalWrite(6,1);

  digitalWrite(7,0);

  digitalWrite(8,0);

  digitalWrite(9,0);

  digitalWrite(10,0);

  digitalWrite(11,1);

delay(5000);

 

  digitalWrite(0,0); //Yellow 2

  digitalWrite(1,0);

  digitalWrite(2,1);

  digitalWrite(3,0);

  digitalWrite(4,0);  

  digitalWrite(5,1);

  digitalWrite(6,0);

  digitalWrite(7,1);

  digitalWrite(8,0);

  digitalWrite(9,0);

  digitalWrite(10,0);

  digitalWrite(11,1);

  delay(3000); 

   

  digitalWrite(0,0); //enables the 3st set of signals

  digitalWrite(1,0);

  digitalWrite(2,1);

  digitalWrite(3,1);

  digitalWrite(4,0);  

  digitalWrite(5,0);

  digitalWrite(6,0);

  digitalWrite(7,0);

  digitalWrite(8,1);

  digitalWrite(9,0);

  digitalWrite(10,0);

  digitalWrite(11,1);

  delay(5000);

 

  digitalWrite(0,0); //Yellow 3

  digitalWrite(1,0);

  digitalWrite(2,1);

  digitalWrite(3,0);

  digitalWrite(4,1);  

  digitalWrite(5,0);

  digitalWrite(6,0);

  digitalWrite(7,0);

  digitalWrite(8,1);

  digitalWrite(9,0);

  digitalWrite(10,0);

  digitalWrite(11,1);

  delay(3000); 

  digitalWrite(0,1); //enables the 4st set of signals

  digitalWrite(1,0);

  digitalWrite(2,0);

  digitalWrite(3,0);

  digitalWrite(4,0);  

  digitalWrite(5,1);

  digitalWrite(6,0);

  digitalWrite(7,0);

  digitalWrite(8,1);

  digitalWrite(9,0);

  digitalWrite(10,0);

  digitalWrite(11,1);

  delay(5000);

  digitalWrite(0,0); //Yellow 4

  digitalWrite(1,1);

  digitalWrite(2,0);

  digitalWrite(3,0);

  digitalWrite(4,0);  

  digitalWrite(5,1);

  digitalWrite(6,0);

  digitalWrite(7,0);

  digitalWrite(8,1);

  digitalWrite(9,0);

  digitalWrite(10,0);

  digitalWrite(11,1);

  delay(3000);  

}