Embedded Network Terminal And Research Of OPC Technology

With the development of the computer communication technology, Ethernet is more and more important, and presents fast trend. More and more embedded systems controlled by MCU apply industry control system. The traditional divide one system in some sub-system, reduce the system's complex extent, but each computer's communication protocol do not have the united standard, so establishing a suit of rule which hardware supplier and software developer must is imperative under the situation for standardizing the access and letting users divorce from the bottom developing. OPC technology specification is a new industry control standard established by OPC foundation, which provides an unitive data-accessing software and hardware interface standard, causing user no more exploit software for different hardware repeatedly, boosting the efficiency, and avoiding the waste of human and material resources.The system is made of MCU and Network-chip, choosing MSP430 and CS8900A. According to the real need and characteristic that the protocol can be cut out, I simplify and realize the TCP/IP protocol stack. The network layer protocol is UDP, assuring the real-time capability of data transmission. The application layer protocol is Modbus, applying the industry control realm. Additional, I design an OPC server in upper monitor, which is used for receiving the data and communicating with OPC client fox inquiring the embedded network terminal.