Use MTA Technology to Implement the Asynchronous Data Transfer within OPC Data Asscess Server and Client

This paper introduces how to use MTA technology to implement the asynchronous data transfer within OPC Data Access server and client.At first,the mechanism of OPC asynchronous data transfer and the advantages of using MTA to implement it are explained.Then more details of the COM multithread technologies are described.A case of using MTA to implement asynchronous data transfer in OPC Data Access server is given out in the end of the paper.