Microprocessor Based Traffic Light Controller

Abstract

This paper describes one of the dedicated applications of microprocessors as the traffic light controller. The project model is fabricated to demonstrate a simulation study on traffic light control at a cross road junction based on Intel 8085 central processing unit (CPU). The model is provided with a facility of control lights (LEDs); (i) for straight traffic flow in North-South (N-S) and East-West (E-W) directions, (ii) for traffic flow in right and left turns, and (iii) for pedestrian crossings. The software for ‘normal mode’ and ‘bold mode’ have been developed. A buffer stage has been designed and assembled to use between I/O interface chip 8255 and LEDs. The work can be extended for, simultaneous multiple junction traffic control using the same CPU, traffic densities being monitored either by photo sensors or switch-board controls.