Research And Realization Of The Dynamic Gateway Based On PROFINET

With the rapid development of industrial control,industrial environment more and more emphasis on automation,communications and network integration,industrial Ethernet technology also came into being,it is the industrial application of the field bus predecessor to provide the cost,data and transmission Speed improvements,the ability to effectively cope with harsh environments,data conflicts,factory noise and plant process needs,from the office to the industrial site to achieve vertical integration.At present,the field bus control system has been widely used in the field of industrial production and control because of its openness,real-time and operability.In the actual production process there are a variety of field bus standard coexistence of the situation,different standards can not be directly connected between the bus,if a large number of switch to industrial Ethernet technology,is bound to cause a huge waste of resources.Therefore,it is urgent and practical to study the interoperability between industrial Ethernet and different standard fieldbuses.In this paper,PROFINET technology,which is one of the international standards of Industrial Ethernet,is researched and developed according to its characteristics.The gateway protocol module of PROFINET and the widely used Modbus bus is designed.The gateway is used as the slave station on the PROFINET side.As the master station,the input and output data can be up to 1490 bytes,support Modbus RTU frame format and four kinds of Modbus standard function code,the configuration is simple,flexible,and through the Web service to the gateway module protocol mapping between the relationship Parameter configuration,to achieve dynamic gateway design,has great market potential,and industrial network communications and automation control technology has a role in promoting.The gateway hardware selects the PROFINET dedicated processing chip ERTEC200 P which integrates the ARM926EJ-S as the communication controller,and realizes the PROFIENT terminal and the Modbus master function module respectively.In addition,PROFINET communication interface with a network isolation transformer RJ45 interface,to achieve signal isolation,improve anti-jamming capability and impedance matching with external components,the external signal interface using optocoupler isolation design to improve the reliability of its communication.Gateway firmware design from PROFINET and Modbus bus OSI communication model,system structure,communication protocol,packet frame structure to start,research protocol mapping,frame transmission technology.Based on the research of Socket in PROFINET IO protocol stack and the principle of HTTP,the embedded Web server is designed to realize multi-task scheduling under eCos operating system and finally realize the functional requirements of dynamic gateway parameter assignment.Finally,use the PLC SIMATIC S7-1500 provided by Siemens as the PROFINET IO controller to build the test environment,construct the message monitoring environment,analyze the PROFINET message by TIA Portal software configuration,Wirshake software capturing packets.Through the Web browser address,quantity and other parameters such as configuration,complete PROFINET IO controller and Modbus device dynamic gateway communication test and analysis.The correctness of the design of this subject is verified.