OPC DA 204 Custom Interface.pdf OPC_20_Automation_Interface.pdf OPC的两个客户端操作文档。一个用于VC，一个用于VB。

OPC Automation接口手册 This specification is an interface for developers of OPC clients and OPC Data Access Servers. The specification is a result of an analysis and design process to develop a standard interface to facilitate the development of serve