Integrated Gateway Study And Design Of Fieldbus PROFIBUS-DP And WiFi

PROFIBUS-DP field bus is widely used in industrial control system,because of its high real-time performance, fast transmission speed, great interoperability and openness. But for the much dust, wet and not conducive to wiring environment of industry or the place of building a temporary control system, the PROFIBUS-DP field bus may be difficult to do. Therefore, the field bus to the wireless network development is the trend of today’s development. According to the actual situation, this paper makes a feasibility study on the field bus PROFIBUS-DP and wireless WiFi network protocol conversion, and determines the technical scheme of the integration of PROFIBUS-DP and WiFi by using the gateway method.1)Through analysis for domestic and international fieldbus and wireless network integration research, integration of the IEEE802.11 protocol and fieldbus can realize theoretically,and can meet the the industrial real-time requirements. This article discusses four methods of PROFIBUS fieldbus and wireless network integration: application layer integration method, wireless relay method, gateway and DDL layer integration method. Summed up the gateway method is suitable for this subject in the design complexity and real-time performance and application environment.2)The communication model and protocol function of PROFIBUS-DP are analyzed. The paper discusses PROFIBUS-DP DDL function,and the TCP/IP protocol stack of WiFi.3)According to IC technology of the PROFIBUS-DP protocol, this paper puts forward the AT89S52 + SPC3 + HLK-RM04 hardware solutions. The circuit design principle and scheme of each hardware module are described in detail: DP protocol module circuit; WiFi protocol module circuit; monitor and reset circuit; RS232 and RS485 interface circuit,and power interface. This paper puts forward the software design scheme of PROFIBUS-DP and WiFi protocol conversion module, discusses the implementation method of PROFIBUS-DP and WiFi protocol conversion in detail, and gives the software design flow chart.4)Building testing environment: in a desktop installation WINAC2009,CP5611A2,STEP7V5.5; designing of PROFIBUS-DP to WiFi gateway communicates with the main station through the RS485 cable; the computer installing WiFi network card and TCP&UDP testing tool is seen as WiFi equipment.Based on the experimental platform, the experimental results show that the system is feasible. for integrating fieldbus and wireless network, a feasible technical scheme is put forward.