Abstract
This design is the use programmable logic controller and microcontroller design a system to cross traffic lights controller. Design is mainly used in Japan OMRON company's CPM2A series of 30 points and 89C51 microcontroller PLC to carry out the design. Cross traffic lights is an important city facilities, which regulate the traffic of the city running, running a city law so that people travel more convenient. The traffic lights make the city controller of traffic lights in accordance with the provisions of the timing and sequence of operation, and on this basis to design a simple road traffic flow can be detected and how much control the traffic flow in accordance with the direction of the traffic lights running time, Traffic lights to guide the traffic in the area can be more efficient.
Key words: traffic lights PLC Intelligent Control MCU