Train Communication Network Gateway Based On Embedded System

Train Communication Network (TCN) is a high-performance and synthetical system about information transimission of control,status monitoring,failure diagnosis and passenger services on present train.Therefore there is no doubt that the devices conforming to the international standard of TCN will have a very promising future.This subject is on the basis of studying network structure of train communication network, have designed and realized TCN gateway equipment that accord with the international standard IEC 61375 and based on the embedded platform. The PowerPC architecture-based processor- MPC860 of Motorola is selected for the gateway equipment , which designed specifically for high-perfoemance telecommunication and network market and have two processor core. In addition selected VxWorks as embedded software platform.This paper has introduced the hierarchical structure of TCN gateway at first. Then Analyzed IEC-61375 and divided the TCN gateway into some important modules. On the basis of to the analysis the data interchange process, a real-time,simple,reliable shared RAM bus arbitration mechanism was designed and used specifical buffer to ensure the integrity of datasets. Meanwhile carried on the demand analysis of TCN gateway equipment ,designed and implemented Manchester Codec,Frame Transceiver effectively ensure the performance of communications interference and correct completion of data transmission.Redundancy Switch to train protection under the failure of uninterrupted communications.analyzed RS485 circuit and designed filter circuit to meet the requirement of signal.MPC860's peripheral circuit (including memory,clock and display) have designed in detail, and also the interface of the bus and peripheral communication interface (including serial interface and network interface), which have met the demand of data communication and stored. Analyzed VxWorks's characteristics and presentated the driver development process based on display control chip and chinese input method designing.The meaning of this subject studied breaks the monopolizing technology of TCN gateway equipment abroad, promoting the development of domestic train electrification. It has laid a certain foundation for the study and develop of the domestic train communicate network equipment.