Arduino program to implement Two way traffic signal system.

Write a program Two - way traffic ðŸš¦ signal and implement it using an Arduino uno board.

Creating a two-way traffic signal system using an Arduino Uno involves controlling multiple LEDs to simulate the traffic lights. We'll use red, yellow, and green LEDs for each direction and create a timing sequence to simulate a traffic light system.

Components Needed:

Arduino Uno
2 Red LEDs
2 Yellow LEDs
2 Green LEDs
6 Resistors (220 ohms each)
Breadboard
Jumper wires
Circuit Diagram:

LED Connections:

Direction 1:

Connect the anode (positive) of the Red LED to digital pin 2 on the Arduino through a 220-ohm resistor.
Connect the anode of the Yellow LED to digital pin 3 on the Arduino through a 220-ohm resistor.
Connect the anode of the Green LED to digital pin 4 on the Arduino through a 220-ohm resistor.

Direction 2:

Connect the anode of the Red LED to digital pin 5 on the Arduino through a 220-ohm resistor.
Connect the anode of the Yellow LED to digital pin 6 on the Arduino through a 220-ohm resistor.
Connect the anode of the Green LED to digital pin 7 on the Arduino through a 220-ohm resistor.
Connect the cathodes (negative) of all LEDs to the GND pin of the Arduino.

Solution

const int red1 = 2;
const int yellow1 = 3;
const int green1 = 4;

const int red2 = 5;
const int yellow2 = 6;
const int green2 = 7;

void setup() {
  pinMode(red1, OUTPUT);
  pinMode(yellow1, OUTPUT);
  pinMode(green1, OUTPUT);
  
  pinMode(red2, OUTPUT);
  pinMode(yellow2, OUTPUT);
  pinMode(green2, OUTPUT);
}

void loop() {
  // Direction 1 Green, Direction 2 Red
  digitalWrite(green1, HIGH);
  digitalWrite(red2, HIGH);
  delay(5000); // Green for 5 seconds
  
  // Direction 1 Yellow, Direction 2 Red
  digitalWrite(green1, LOW);
  digitalWrite(yellow1, HIGH);
  delay(2000); // Yellow for 2 seconds
  
  // Direction 1 Red, Direction 2 Red
  digitalWrite(yellow1, LOW);
  digitalWrite(red1, HIGH);
  delay(1000); // All red for 1 second
  
  // Direction 1 Red, Direction 2 Green
  digitalWrite(red2, LOW);
  digitalWrite(green2, HIGH);
  delay(5000); // Green for 5 seconds
  
  // Direction 1 Red, Direction 2 Yellow
  digitalWrite(green2, LOW);
  digitalWrite(yellow2, HIGH);
  delay(2000); // Yellow for 2 seconds
  
  // Direction 1 Red, Direction 2 Red
  digitalWrite(yellow2, LOW);
  digitalWrite(red2, HIGH);
  delay(1000); // All red for 1 second
  
  // Direction 1 Red off, reset for next cycle
  digitalWrite(red1, LOW);
  digitalWrite(red2, LOW);
}

Output

Pin Definitions:

Pins 2, 3, 4 are assigned to red, yellow, and green LEDs for Direction 1.
Pins 5, 6, 7 are assigned to red, yellow, and green LEDs for Direction 2.

Setup:

Set all LED pins as OUTPUT in the setup() function.

Loop:

The main loop() function alternates between the states of the traffic lights for the two directions.
Each direction gets a green light for 5 seconds, a yellow light for 2 seconds, and then both directions get a red light for 1 second.
This sequence ensures that one direction has a green light while the other has a red light, followed by a brief period where both directions have a red light.

Steps to Implement:

Assemble the circuit on the breadboard according to the diagram.
Connect the Arduino to your computer.
Open the Arduino IDE, copy and paste the code, and upload it to the Arduino Uno.
Observe the LEDs as they cycle through the traffic light sequence.

Programming Examples

Arduino program to implement Two way traffic signal system.