Traffic Light Controller Circuit Documentation

Summary

This document describes a simple traffic light control system designed using an Arduino UNO microcontroller and a custom traffic light module. The system operates a traffic light sequence with three stages: green, yellow, and red. The green light is active for 5 seconds, followed by the yellow light for 2 seconds, and the red light for 5 seconds. This sequence repeats indefinitely to simulate a traffic light control system.

Component List

Arduino UNO

• Description: A microcontroller board based on the ATmega328P.
• Purpose: Acts as the central control unit for the traffic light system.
• 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.
• D3: Connected to the Green pin of the Traffic Light module.
• D2: Connected to the Yellow pin of the Traffic Light module.
• D1: Connected to the Red pin 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 finally the red LED for 5 seconds. This
 * sequence 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

Description: The code provided is an Arduino sketch that defines the pin connections to the traffic light module and contains the logic to cycle through the green, yellow, and red lights. The setup() function initializes the pins connected to the LEDs as outputs. The loop() function controls the state of each LED, turning them on and off in sequence with specified delays to create the traffic light effect.