Research And Interface Design Of PROFIBUS And HART Communication Protocol Convertor

In the Information Age of the world today, various fields are forward to the informationtechnology, especially played of incisively and vividly in the fileld of automation.Automation technology progress fully benefit from computer digital communication andinformation technology, and the development of fieldbus technology incorporate computercommunication technology into the field of industrial automation.At present, there are varietyof international fieldbus and they won in the fierce competion to own their application market,so various fieldbus coexistence will last a very long period of time in the future. But eachfieldbus have their own characteristics and the differences between them are very large, itbrings a lot of trouble for information interaction and integration between heterogeneoussystems. The different systems interconnection is necessarily the future development trend ofthe fieldbus technology.The research of PROFIBUS and HART communication protocolconvertor is to meet this trend and has very important significance.Hardware structure of PROFIBUS and HART protocol convertor based on PROFIBUSprotocol processing module,HART protocol processing module and main control module isdesigned and realized in the research.Among them, SPC3,as core of the PROFIBUS protocolprocessing module,is a special protocol processing chip. It realizes PROFIBUS protocolprocessing and improves the efficiency of communication protocol processing.HARTprotocol processing module relies on HT2012and external analog circuit to realize theprotocol processing.The main control module uses a32-bit DSP chip(TMS320F2812),as wellas a variety of functional circuits,to further improve the efficiency of protocol conversion.On the basis of hardware, the lower computer software and the upper computer softwareis designed and accomplished.The lower computer software includes PROFIBUScommunication software and HART communication software.The communication softwarecooperate with each other, realizes the information transfer work between PROFIBUSprotocol and HART protocol.The upper computer software uses VB to design the displayinterface of the PROFIBUS and HART communication protocol convertor. The correct rateof protocol conversion, conversion status and conversion results are judged. The displayinterface effectively improves the efficiency of protocol conversion. Finally through testing two communication interface of the communication protocolconvertor, the results proved that the convertor is both up to PROFIBUS standard and HARTstandard and the scheme of protocol conversion implementation is feasible.But its reliabilityand security in practice remain to be further practice and validation.