Design Of Protocol Conversion Unit Between FC-AE-1553and MIL-STD-1553B Based On FPGA

With high reliability and flexibility, MIL-STD-1553B data bus has been widelyused in avionics systems. Nowadays, with the continuous progress of the aviationindustry, the complexity of avionics systems increases at a high rate, and traditionalMIL-STD-1553B can’t meet new requirements such as higher transmission speedand decentralization of control.Fibre channel(FC) is a reliable, fast, low-latency serial bus supporting flexibletopologies and multiple upper level protocols. Avionics developers have been usingfibre channel for high-reliable, real-time networking. FC-AE-1553is a technicalreport describing a specific subset of fibre channel for use in defense and avionicapplications. The FC-AE-1553report specifies compliance criteria for the MIL-STD-1553B upper layer protocol. FC-AE-1553inherits conventional features of MIL-STD-1553B and excellent network performances of fiber channel.Protocol conversion between FC-AE-1553and MIL-STD-1553B is significant forthe development of new generation avionics equipments. With the capability ofprotocol converting between these buses, new avionics equipments can not only takeadvantages of the network features of fibre channel, but also provide compatibilitiesfor the previous generation MIL-STD-1553B procucts. By this means, the existingdevice resources can be used continously, and smooth transition to new technologycan be achieved.This paper proposes the protocol converting solutions between FC-AE-1553andMIL-STD-1553B, and studies NC-to-RT (Network Controller to Remote Terminal)transmitting process.Design of the protocol conversion unit is based on FPGA, by using the Quartus IIsoftware and verilog HDL. The protocol conversion has three steps: convertingcommand frame to command word, converting data frame to data words andconverting status word to status frame. The process of converting command frame to command word includes severalmodules: frame decomposition(command), CRC32cyclic redundancy check,8b/10bdecoder and Manchester encoder. The process of converting data frame to data wordsis similar to the previous process. The difference is that only one single commandword message can be in a command frame, while the number of data word messagecan be greater than one. The process of converting status word to status frame alsoincludes several modules: Manchester decoder,8b/10b encoder, CRC32encoder andframe packing(status).Simulation results show that each module of the protocol conversion unitperforms good, and the protocol converting is successful. Research of the protocolconversion between FC-AE-1553and MIL-STD-1553B is valuable for further study.