Research And Implementation Of Embedded TCP/IP Based On Single-chip-computer

Along with development and popularization of computer technology and network technology, pocket embedded equipment with single-chip computer have already applied extensively in industrial automation, official automation and building automation etc.To realize the long-distance data-collected, 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.A method, which achieved the connection of network card chip RTL8019AS of ISA of Realtek Inc and Internet, is given in the paper.The network card chip is controlled by 8-bit single-chip computer P89C51RD2 of Philips Inc. The interface of Ethernet network is designed in hardware and the driver of network card control and TCP/IP protocol is designed in software.The paper includes the introduction of characteristic of P89C51RD2 microcomputer, the reason of choosing network card chip RTL8019AS, giving the circuit of hardware interface and the explanation of mostly periphery parts.The design of the driver of network card is introduced in the paper. The interior structure of network card chip, the main pins, the frame format of Ethernet, the principle of receive &send data package, the operation of DMA are described in detail and the flow chart of program is also given out.TCP/IP is an ensemble of many protocols. Considering the limited resource of 8-bit single-chip computer, some functions are reduced to allow single-chip computer to go internet but TCP/IP protocol and package format are explained in particular. The work 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 research in this paper and the result shows that it is feasible. It can provide data for long-distance data-collected, diagnosis, software upgrade, etc. It can be turn into reality.