The Research Of Embedded-System Connecting To The Internet By Dialing

The rapid development of the Internet technology has made it combined with control technology such as industry, agriculture, information household appliances, etc day and day close. So the application for Internet should have more high-level request corresponding to the development of the Internet technology. In an era of information sharing, most electronic products need imbed Internet communication protocol stack and can be connected to the Internet whenever and wherever based onthe open Internet standard. This puts forwar to ow to realize connection to the Internet in limited resources.The embedded-system means a special-purpose computer system that is used for carrying out the independent function. It emphasizes coordination, merger and cut-back in hardware and software in order to meet the requests such as function, cost, volume and consumption, etc. With the transmission media provided by the existing Internet facility for the embedded-system connecting to the Internet, it is not very high to realize the imagination of connecting the embedded-system to the Internet at the expenses of the hardware and software. What we do is only to combine the embedded main controller with the transmission media.Considering the existing IP address shortage issue, it's not possible to assign a static IP address for each user of the embedded-system. So the author adopts the scheme of assigning dynamic IP address-connecting to the internet by dialing. Weighing the pluses and minuses of various kinds of methods and the similarity of realizing the scheme, finally, the author puts forward the scheme of connecting the embedded-system to the Internet by dialing up on the telephone.Aiming at the characteristic of dialing embedded-system and at especially its software part: TCP/IP protocol, the author cuts out unnecessary protocol of each layer, at the same time introduces essential protocols of the system at minimum expenses in detail. Particularly the author explains Point-to-point protocol (PPP) realization exhaustively. Also the author sums up the hardware part. Modem is an interface device of the embedded-system and the Internet. Because modem can convert data that flow in the network, the author introduces working mechanism of Modem and relevant instructions named Hayes.Finally, the author designs the application system -Dial embedded system anddistance control system, and gives the detailed realization scheme respectively.