The Research And Realization Of Hardware For USB Devices

With the development of the network, the security of computer is playing an important role. Based on the current available security system models, we have developed a new practical USB interface security system with the feature of the new interface.Universal Serial Bus (USB) is a new technology about interface in computer application. USB has been used widely since the Windows98 operation system supported the USB interface in computer. USB is one of the most important developments in PC peripheral interconnect technology since the introduction of serial and parallel ports in the early 1980's. It is a fast, bi-directional, isochronous, low-cost, dynamically attachable serial interface that is consistent with the requirements of the PC platform of today and tomorrow[1] The benefits of USB, such as easy to use, true of plug and play, high performance, and reduced overall system cost, are just a few of the reasons this technology has gone from specification to product development in several years.Author of this article researched whole USB technology and made a USB solution for PC's Encryption System. Author also realized a USB Encryption System as a instance of this solution. This paper makes a full explanation of USB interface of design and USB bus technology. It emphatically describes the selecting and application of USB interface chips. In addition, it discusses the development of basic function of USB Encryption System and presents a new opinion about this design, which can make a very active influence in practice. This article studied USB interface key technology, put forward the actual solution.The whole system is composed of three subsystems: 1. USB 1.1 interface subsystem, 2. Windows driver and application program, 3. FPGA encryption subsystem. This paper consists of the hardware and firmware design of the device. It describes the blue print of USB structure and design of USB firmware in detail. The paper brings forward that module method is a very efficient way to design the circuit including modules of USB chip, I2C BUS and security. Firmware program design mainly shows the step of development and flowchart with corresponding code segment. Be superior to firmware program developed in assemble language traditionally, our program is completed by C language, which improves program's movable and legibility. On the part of driver, it introduces the concept of facility criterion and facility driver. After explaining Windows driver develop module, it presentations integration develop environment, which design USB driver program and a concrete instance. Be different than usual development method, we make use of two tools (DriverWorks and Windows DDK) creating program framework by Driver Wizard in DriverWorks, and then, programming by DDK. In a word, proved by experiment, the thesis achieved the expected goal: accomplish the prototype research and development of encryption system with USB 1.1 interface.At the end of paper, some bugs are put forwards at present. Simultaneity, we show several ways to solve them in the future.