Research Development And Implement Of OPC Data Access Server

With the Computer technology continues to develop, the types used in the field ofindustrial Control software and hardware, system integration is becoming increasinglyComplex and difficult. So, whether it is a unified set of Common standards is necessary forthe Customer or developer.OPC DA is mainly to provide longitudinal data in the field layer and aplication softwareintegration and interoperability. OPC Client and server communicate through the standardinterface with one or more different Providers. OPC DX defines a common interface, differentbus protocol devices and controllers through ethernet direct data exchange possible.From the application and development of OPC technology, OPC DA data accessspecification is the core of the practical application and the most widely used in industrialcontrol systems, application software, OPC DA seems to have become the must interfacestandard. Industrial ethernet-based control system has become a popular trend, and OPC DAas an open software technology,is used in system integration applications.The dissertation first introduces the background of OPC technology and researches theOPC Data Access specification,Secondly it introduces COM technology which is the core ofimplementing OPC, and describes the cooperation of client and out一of一PrecessComponent. The emphases of this dissertation is to develop OPC DA Server,The dissertationdesigns the stricture of OPC server and resolves some difficulty in the Process ofdevelopment. Used the third-party open-source propckit library, It implements the basicfunction Of OPC server with delphi,at last gives a detailed test Method of the OPC serverThis paper provides a contribution of the following aspects:First, Carefully study the implementation of standards and technical details of OPC, thegrasp the key of OPC technology.Second,Study the open-source class library propckit，package out the TRtt ItemServerclass.based on OPC Itemserver class.transformed an OPC item to an Properties of aclass.Greatly simpifies the development of OPC,put forward a common method of the OPCdevelopment. The third,put forward technical structure and details of the combination of OPC anddatabase systems, and database methods.Fourth， put forward the overall structure of the OPC Data Monitoring SystemFifth，Use the delphi programming method to test the OPC server...