Design Of LED Highway VMS Control System

The rapid development of road traffic brings a huge security risk as well as remarkable social development, the emergence of intelligent transportation systems provide ways and means to effectively ease the traffic pressure, improve traffic lane security. As an information-publishing terminal of the intelligent transportation system, highway VMS plays an important role in the publishing of the command information, prompting weather warning and broadcasting emergency information. Currently existing VMS mostly adopt the program of IPC+PLD or DSP+MCU, while the design has many defects such as the system complex,-difficult to maintain, and the lack of processing power, communication means inadequate and so on, existing VMS are unable to meet the new demand of the road traffic.According to the defects and the development trends of ITS, combined with embedded technology and modern communications technology, a new LED VMS is designed in this paper. The VMS adopts the architecture of ARM+Linux, use AT91SAM9G45as the control kernel, communications with FPGA through the LCD interface. Design a communication protocol stack and corresponding communication data structure which can be extended in communication mode and communication protocol. The VMS has multiple means of communication, such as3G,10M/100M adaptive Ethernet and serials communication, it can provide stable and effective communications link as well as a high degree of flexibility when it is installed in different environments. The key modules of software are designed with hardware independence, and can be transplanted across platforms. The animation module and communication module have good scalability, can upgrade conveniently according to need. The new designed VMS showed good stability in the high and low temperature tests and pressure tests and meet the design expectations.