In recent years, with the rapid development of science and technology, SCM applications are constantly go deeper and Meanwhile promote traditional control technology is developing rapidly updated. Automatic control of the SCM application system, the microcontroller is often as a core component to use, SCM knowledge alone is not enough and should be based on specific hardware structure, and the specific characteristics of the target application software combination to be improved. Traffic signal control many ways, the design of the control system of traffic lights to MCS-51 microcontroller-based controllers, appropriate for the memory, keyboard / display, a simulated light of the expansion, forming manipulator movements analog control system. The use of LED lights designed crossroads simulation of the traffic lights, the use of interface device has been the single pulse generator, single pulse generator produced a negative pulse to generate external interruption simulated emergency vehicles through. The traffic light control system used in the procedure delay timer is used the method to make full use of the computer's hardware resources. improve the efficiency of enforcement. The system used in the compilation process from the language, object program memory space occupied less, run faster, Senior language is irreplaceable purposes. The system user-friendly, better controllability. Now with the rapid economic development, and the increasing population of the community, to alleviate traffic congestion caused by a series of problems can play a certain role in the control.