Toussaintduk/-Traffic-ligh-controller

This project implements a traffic light controller for a four-way intersection with pedestrian crossings, designed as part of the EEE 3261 – Microcontroller & Embedded Systems course at the University of Rwanda. The system ensures efficient traffic flow and pedestrian safety using AVR microcontroller I/O operations, timers, and interrupts # 🚦 Four-Way Traffic Light Controller with Pedestrian Crossings (AVR) ## 📘 Background Traffic light controllers are **critical embedded systems** that manage traffic flow and ensure pedestrian safety at intersections. This project focuses on **designing and implementing** a four-way traffic light controller with pedestrian crossings using **AVR microcontrollers**, applying key concepts such as **I/O operations, timers, and interrupts**. This work was completed as a **class assignment** under the supervision of **Prof. Kizito NKURIKIYEYEZU** for the **EEE 3261 – Microcontroller and Embedded Systems** module in the **Electrical Power Engineering Department** at the **University of Rwanda**. --- ## 🧰 Hardware Setup ### 🔧 Components Used | Component | Function | |------------|-----------| | **ATmega16/32** | Main microcontroller | | **LEDs (12 total)** | Traffic lights for four directions (N, E, S, W) | | **Pedestrian LEDs (4 pairs)** | Walk/Don’t Walk indicators | | **Push Buttons (4)** | Pedestrian crossing request inputs | | **Buzzer** | Audible pedestrian warning | | **7-Segment Display** | Countdown timer display | ### 🧩 Port Configuration - **North LEDs:** PB0–PB2 (R, Y, G) - **East LEDs:** PB3–PB5 (R, Y, G) - **South LEDs:** PC0–PC2 (R, Y, G) - **West LEDs:** PC3–PC5 (R, Y, G) - **Pedestrian LEDs:** PD0–PD3 - **Buttons:** PD4–PD7 (with pull-ups) - **Buzzer:** PA0 - **7-Segment Display:** PA1–PA7 --- ## ⚙️ System Features ### 1. Basic Traffic Light Control - Standard **Green → Yellow → Red** sequence - **North/South** and **East/West** directions operate as synchronized pairs - Timing parameters: - Green: 20s - Yellow: 5s - All-Red: 2s ### 2. Pedestrian Crossing System - Pedestrians press buttons to request crossing - System completes the current vehicle phase before activating pedestrian mode - **Countdown timer** displays remaining crossing time - **Buzzer** activates during crossing phase - **Crossing time:** 10 seconds (final 3 seconds have faster b …