The Exploitation On The Telecommunication Module Of Computer Based On The Interface Of USB

When you want to transmit a file from the local computer to the remote computer without the condition of internet, the question will be involved that you must connect your computer with the internet by GPRS (General Packer Radio Service).GPRS network of China Mobile covers 31 provinces and more than 240 cities in the whole country at present; it covers the widest coverage area with optimum quality and high capacity at present in China. At present, USB interface which with the characteristic of 'Plug & Play' makes it applied to all respects more and more widely. So the question that we should solve is: A kind of telecommunication mould should be researched. The file that will be sent can be sent into the communication module when the local computer links to the communication module through USB interface. And then encrypt plain text into cipher according to the certain algorithm in the module by ARM chip microcomputer. The cipher that be encrypted will be sent to base station through GPRS to the Internet. The cipher will be received in form of the E-mail at the mail server finally. The plain text will be got through the appointed deciphering algorithm on the server.The main task of this subject is: Bring forward general planning of the telecommunication module based on USB interface and the software and hardware should be designed.The main work of this subject includes:(1) Structure of the Universal Serial Bus (USB) and operation principle has been analyzed. Including topological structure of the bus, physics layer of USB, USB equipment, USB host computer, USB bus protocol;(2) The RISC structure of ARM has been analyzed. Including several common kernel series of ARM has been analyzed. And the basic characteristic, orders, the developing instrument and development environment has been deep analyzed.(3) Carry on the general planning and design of the software and hardware based on this foundation.(4) The detailed design of hardware has been designed. Including the whole structure, the power module, the reset circuit, the Flash memory interface circuit, the SDRAM interface circuit, the serial interface circuit, the communication module, the chip microcomputer control module, etc.;(5) The detailed design of software has been designed. Include the divide the work of every module procedure, main loop, the layers of hardware pick-up module, the orders' interface of PDIUSBD12module, the interrupt service program modules, the protocol layers module, etc.;(6 ) The hardware circuit has been tested; insure it can work normally;(7) The software should be debugged. And then jointly debugged should be done with the hardware. The required function of the whole system should be reached finally.