The Design And Development Of MVBC Based On FPGA

With the increasing popularization of the electric multiple units (EMUs) and consequently the continuous increase of the information transmission on the train, the train communication network (TCN) will play a more and more important role. It, also known as the standard IEC61375-1, divides the TCN into two parts: the wire train bus (WTB) used for connecting dynamically reorganizable vehicles and the mutifunction vehicle bus (MVB) used for connecting fixed devices in a vehicle. Related products and technology applied in domestic trains are mainly imported from other countries. While the study and development in this field are still in primary stage in our country, the overseas monopolization has not been broken yet, which really affects developing train communication devices with independent intellectual property and makes no profit in the establishment of our own train communication network standard.Because of above reasons, the TCN is researched and the MVB is technology deeply analyzed in this paper According to the TCN protocol, devices attached to the MVB are classified into five groups and each device should join MVB by the bus controller. Therefore, the development of the mutifunction vehicle bus controller (MVBC) is crucial in the MVB technology applications. After well understanding and digesting the TCN protocol, a scheme is proposed to implement the MVBC with FPGA. The functions of the MVB device controllers of class 2, 3, 4 are integrated into one piece of FPGA in this scheme.According to the TCN protocol, the MVBC is mainly divided into eight function modules: encoder, decoder, telegram analysis unit, internal register array, main control unit, interrupt logic, traffic memory controller and address logic. In the design, each module is described as a RTL circuit with Verilog HDL, and four of them are mainly realized. These modules are synthesized by 1SE and Synplify Pro. Finally, the wave simulation and verification of such modules are made in ModelSim.In laboratory circumstances, the functions of the MVB controllers are validated and their frame waveforms are in complete conformance with the TCN protocol. Based on the above results, it can be believed that the scheme of implementing the MVBC with FPGA has a fairly good operability.