Research And Implementation Of Eight Single-chip Ethernet Access

Along with development and popularization of computer technology and network technology, pocket embedded equipment with single-chip computer have already appl-ied extensively in industrial automation, official automation and building automation etc. To realize the long-distance data acquisition, control and so on, the network has become a trend of the development of new generation embedded system. It has important realistic significance and economic value to research the connection of embedded system and Internet.After studying the existing ethernet solutions of single-chip computer, a software method has been proposed for embedding TCP/IP protocol in single-chip computer which has simple hardware interface, fewer peripheral devices, lower price, shorter development period. And its realization depends on controling the network interface chip DM9000.The interface of Ethernet network is designed in hardware and the network interface chip DM9000 is controlled by 8-bit single-chip computer AT89C52 of ATMEL. The driver of network interface control and TCP/IP protocol is designed in software. It uses C51 language on KEIL μVision 2 software platform to program the system and Borland C++ Builder 6.0 to program the upper computer. Considering the limited resources of 8-bit singlechip computer, some functions are reduced to alow single-chip computer to go Internet but TCP/IP protocol and package format are explained in particular. The process flow of system and the flow chart of each TCP/IP module are given out, too.The connection of single-chip computer and Internet is researched in this paper and the result shows that it is feasible. It can provide data for long-distance data acquisition, diagnosis, software upgrade, etc.