#Define traffic light code

This process continues as a cycle and the timing for changing the LEDs can be displayed with the use of a seven-segment LED display in this project. At a particular period of time, only the green light holds ON and the other lights remains OFF, and after sometime, the changeover traffic light control from green to red takes place by making the succeeding change for glowing of yellow LED. The LEDs get automatically switched on and off by making the corresponding port pins of the microcontroller high, based on the 8051 microcontroller and its programming done by using KEIL software. Seven-segment display is connected to the port2 pins of the 8051 microcontroller with a common anode configuration. The LEDs are interfaced to the Port zero of the microcontroller and are powered with 5v power supply. This circuit diagram makes use of a crystal oscillator for generating frequency clock pulses. An 8051 Microcontroller is the brain of this whole project and is used to initiate the traffic signal at the intersections on road. In the above circuit diagram of traffic light controller,a seven-segment display is used as a counter display, and three LEDs are used for the purpose of traffic light control. Similarly,lighting of the amber/orange light for a short time of transition represents a signal to prepare to stop, and the Illumination of the red signal disallows any traffic from going on. In a typical cycle, turning on of a green light allows traffic to continue in the way indicated. Typically traffic lights consist of three types of colored lights such as red, orange and green.

In China, there were unsuccessful efforts to change the importance of “red” to “go” during the Cultural Revolution.

#Define traffic light code

Traffic light control system uses a worldwide color code (a specific color order to enable color recognition for those who are color blind). Traffic light control assigns a right way to the road users by using lights in normal colors (red – amber/yellow – green). Traffic lights have been fixed allover the world in many cities.

Traffic lights are also named as stoplights, road traffic lamps, traffic signals, stop-and-go lights which are signaling devices placed at road crossings, everyday pedestrian crossings and other locations to control competing flows of traffic.