Desgin And Application Of Server/Client Based On The OPC DA Technology

With the developing of computer technology, more and more software and hardware are used in industry control field and system integration becomes more complex than before. So it is very necessary to use the same standard to communication for both user and vender. OPC is such a standard that we need. OPC means OLE (Object Linking and Embedding) for Process Control. OPC was put forward in solving communication between application software and vary drives of devices. It makes the work more efficient. So it is increasingly attached importance to by manufacturers.The paper develops OPC server based on OPC specification. In this paper, the background and Data Access specification of OPC technology are introduced, then the principle and mechanism of OPC are described.Meanwhile, the base of OPC— COM is taken apart thoroughly. This paper introduces the ties between OPC and COM, and presents the Sever frame, implementation and the course to carry it out. Referring to the Data Access Custom Interface Standard, Version 2.0 pressed by OPC Foundation, local server is achieved ,then client is carried out. By testing, the client is able to connect the local server and realizes basic instrument such as read and write.