The Research And Realization Of OPC Client Software Based On VC

With the development of Control technology, Computer technology, Network Communication technology, automation system is more and more urgent to share large scale information, and needs more opened industry control system. But traditional DCS, FCS control system applied in industry use its network and agreement, lack unified interface standard, it would be difficult to connect other systems and meters."Information isolated island"is formed and difficult to change data with external systems and meters.OPC applies OLE (Object linking and Embedding) technology into industry Process Control Fields, and provides a kind of standard data access method.The paper studies deeply OPC DA specification,designs and develops OPC client software based on COM technology, adopted Visual C ++6.0 as the development tool of cilent, made a detailed analysis from whole to part on the concrete realization of the OPC cilent. The paper provides main methods to implement it, provides main function and critical code, goes deep into register of OPC server and alternation. Tests have been made to testing the function of the OPC client software, the result of testing indicated that the basic function of this OPC cilent has universality, finally we obtained the general method of design OPC client. It is critical to realize integration of distributed and isomerous system which is close in system software and is bad interoperability, this thesis has its significance.