Traffic Light Controller Circuit Documentation

Summary

This document describes a simple traffic light control system implemented using an Arduino UNO microcontroller and a traffic light module with three LEDs (Green, Yellow, and Red). The Arduino UNO controls the LEDs to simulate a traffic light sequence. The green LED is illuminated for 5 seconds, followed by the yellow LED for 2 seconds, and then the red LED for 5 seconds. This sequence repeats indefinitely to mimic the operation of a standard traffic signal.

Component List

Arduino UNO

• Description: A microcontroller board based on the ATmega328P.
• Purpose: Acts as the central controller for the traffic light system, driving the LEDs in the sequence.
• Pins: UNUSED, IOREF, Reset, 3.3V, 5V, GND, Vin, A0-A5, SCL, SDA, AREF, D0-D13

Traffic Light

• Description: A module with three LEDs representing a traffic light.
• Purpose: Displays the traffic light sequence controlled by the Arduino UNO.
• Pins: Green, Yellow, Red, GND

Wiring Details

Arduino UNO

• GND: Connected to the GND pin of the Traffic Light module to establish a common ground.
• D3: Connected to the Green LED of the Traffic Light module.
• D2: Connected to the Yellow LED of the Traffic Light module.
• D1: Connected to the Red LED of the Traffic Light module.

Traffic Light

• Green: Connected to pin D3 on the Arduino UNO.
• Yellow: Connected to pin D2 on the Arduino UNO.
• Red: Connected to pin D1 on the Arduino UNO.
• GND: Connected to the GND pin on the Arduino UNO.

Documented Code

/*
 * This Arduino sketch controls a traffic light system with three LEDs: green, 
 * yellow, and red. The green LED stays on for 5 seconds, followed by the yellow 
 * LED for 2 seconds, and then the red LED for 5 seconds. This cycle repeats 
 * indefinitely.
 */

// Pin definitions
const int greenPin = 3;
const int yellowPin = 2;
const int redPin = 1;

void setup() {
  // Initialize the digital pins as outputs
  pinMode(greenPin, OUTPUT);
  pinMode(yellowPin, OUTPUT);
  pinMode(redPin, OUTPUT);
}

void loop() {
  // Turn on the green LED
  digitalWrite(greenPin, HIGH);
  delay(5000); // Wait for 5 seconds
  digitalWrite(greenPin, LOW);

  // Turn on the yellow LED
  digitalWrite(yellowPin, HIGH);
  delay(2000); // Wait for 2 seconds
  digitalWrite(yellowPin, LOW);

  // Turn on the red LED
  digitalWrite(redPin, HIGH);
  delay(5000); // Wait for 5 seconds
  digitalWrite(redPin, LOW);
}

Filename: sketch.ino

This code is written for the Arduino UNO and is responsible for controlling the traffic light sequence. The setup() function initializes the pins connected to the LEDs as outputs. The loop() function then controls the state of each LED, turning them on and off in the sequence described, with appropriate delays between the transitions.