Design And Realization Based On Interlinking Of Field Bus And Ethernet

The rapid development of the computer network, communication and control technology has induced the profound transformation of the industry control field. The exchange of communication is spreading all over the world, from factory equipment layer to control and supervision layer, from workshop, factory and enterprise to the market all over the world. At the present time, the first floor control network that constituted by the field bus widely applies in the industry control domain, but the most important choice of the management and information network is Ethernet However ,the demand of the enterprise "manage-control" integration and the enterprise information system urgently need the combination of control network and the management, the information network, and realizing information sharing in the scope of the whole factory and the world.This article embarks from the development present situation of the control network and the information network, particularly analysis the characteristic between the field bus and the Ethernet ,introduced two kind of plans that solves the control network and the information network fusion problem, and elaborated two kind of plans advantages from the actual project application angle, finally according to the actual situation proposed "field bus + Ethernet +MODBUS " scheme and enduced the "CAN-Ethernet" embedded gateway.The article introduced the field bus, the Ethernet network architecture and the principle, including CAN2.0B, TCP/IP,MODBUD/ TCP standard protocol in detail, based that, discussed the network architecture, the ideal of protocol conversion and network model of "field bus + Ethernet +MODBUS/ TCP "plan, and put forward that using the OPC technology to sovles the mutually operational question between I/O hardware equipment as well as software. Then, the choice of gateway hardware platform must based the actual industrial application and considerated the various factor, including development cost, the development cycle, price, the reliability and so on.Finally specifically introduced the programming of the gateway, the gateway server software and the realization process, discussed the multi-thread programming and thebuflFer design with emphasis.