OPC数据访问服务器双向通信机制的实现

VCS2是由广东肇庆维光仪表有限公司委托开发的小型DCS系统，是一种针对流程工业中小型单元设备的过程控制、以提供控制品质为核心、以工程控制为重点的完整的小型DCS，主要应用在各种中小型工厂的控制系统中。本文详细介绍了小型DCS系统VCS2的0PC数据访问服务器开发过程中双向通信机制的实现。

The Realization of Bidirectional Communication Mechanism for OPC Data Access Server

VCS2, a kind of mini DCS, developed under authorization of WeiGuang Zhaoqing Instruments Company, was designed for mini devices of process industry. VCS2 offers engineering control, quality control and can be used in variable control system of small or medium-sized factory,with the rapid progress of technology in computer, network, and communication, traditional design methods of control system software can't meet the need of the development of era, because of the shortcomings such as discommodious ness of update and transplant. In order to solve these problems, in the VCS2, OPC (OLE for Process Control) technology was used. OPC is an application of OLE (Object linking and embedding) technology in process control, which supplies uniform specifications for the design of industry automation software. The aim of OPC is to provide a kind of normative communication mechanism between date resources of devices or of database in control room. This paper discusses the development process of OPC data access server in VCS2.