Ethernet-based GPIB Controller Design And Implementation

With the electron technology developing, people have improved the test technology widely; the information and resource of instrument can be shared, at the same time, control the instrument can be controlled from distant place. GPIB-ENET controller is so in dire need of development. The article introduced the basic principle, design project and realization of the controller principally.Internet technology developing resolve the problem, which is the limit from instrument's number and test distance on the bus to the test task. The embedded system is connected into Internet, it is convenience and cheapness to transfer the information to everywhere in the world, it is not only realize the instrument' control form far away, in another sense, but also the instrument has been being a part of the Internet resource for share. The main difficult is, all kinds of communication protocol on Internet demands the computer memory, the compute speed performance are all very excellence, but in embed system, except for the 32bit computer, the more exist is 8bit and 16bit CPU, supporting TCP/IP Internet protocol will impropriate a mount of system resource, therefore, resolve the difficulty is the pivotal problem.It's a mature technology to realize Internet instrument in PC, However, with the development of technology and practical demand, it's necessary to realize Internet in embedded system, for example in instrument and electrical appliance, to realize remote measure, control and share information. But it's difficult to embed the complicated protocol of TCP/IP into system because of the limited resource (ROM, RAM and speed), especially in 8bit MCU. We analysis the technology of embedded Internet and provide a successful application model. The whole system consists of two parts-client and server, the server is composed of Rabbit 2000,imafine model and interface circuit in hardware, the special software realize TCP/IP, UDP, IP, ARP protocol, and analog the bottom imagine interface. The client, based on PC, is responsible to sending commander, transferring data, recovering imagine etc, the system can realize Internet control and imagine acquisition, transfers and recovery. Instrument's control from far away, and the share for the instrument's resource and so on, lots of functions, at the same time, the accessorial serial port connected the network can realize the more equipment's communication with the internet, so the controller has quite practical role and economic benefit.