Design And Development Of MVB Communication Board Based On VME Bus

ABSTRACT:Security of traffic signal system can directly affect weather the trains are running safely and efficiently, it is related to the safety of the passengers, to ensure the security signal system, specialized research and design important component of the rail transportation security computer, it has a theoretical and practical significance.In recent years, Train Communication Network (TCN) has been widely studied and applied in the field of rail transportation in China.It sets the train control, fault diagnosis and information processing of the train service in one, and has become a key technology of modern high-speed train control system. It includes WTB(Wire Train Bus) and MVB(Multifunction Vehicle Bus).Research start from status of the project at home and abroad, it is around the modern rail traffic running information transmission real-time and reliability.Currently there is little research of MVB communication board for vehicle security computer in our country, rail transit needs such issue deeply.This thesis combines the TCN network and vehicle security computer technology, and proposed a new MVB communications board design with VME bus interface.Communication board connects different types of bus including the VME bus and MVB bus, it realizes data transfer by running software across the bus. In addition, it gives a variety of convenient storage and communication interfaces, such as UART serial port, USB interface and ethernet interface.Firstly, the thesis research the relevant technical theory applied, and proposed an overall design, then it designes and implements communication board hardware based on MVB and VME bus interface,at last, it gives the hardware implementation. The design uses three Take two synchronous redundant computing unit structure, the security and real-time meets the needs of general stations and roads. This system takes ARM controller as the core to achieve the physical layer signal conversion, and completes protocol conversion by running the communication protocol in its procedures, realizes data transfer across the bus.Secondly, the thesis details software design of communication board.Software is mainly divided into three parts:the ARM controller module,the VME bus interface module, and the MVB bus module. ARM controller module includes the data transmission part and the communication interface section. In this thesis, block diagram and flow chart descriptions of each module explains the key points of program design.Finally, this thesis introduces the test and debugging process, debugging process verifies the correction of the design.To verify weather the device can work normally under the MVB network, network debugging is conducted in the lab with EMD distance,the final experimental results shows that the communication of the system is normal. At last, the thesis summarizes the work according to the experimental results and phenomenon, and rose refinement and improvement in the future.