The Implementation Of USB Device Interface IP Core

With the development of computer technology, various external deviceinterfaces were facing serious problems such as the conflict of I/O, the inability ofplug-and-play etc. All of these problems restricted the growth of external devices.Under this background, USB (Universal Serial Bus), which is low cost andplug-and-play, came into being. Its appearance has taken a very important role for thefurther development of computer. According to the tendency of requiring USB, thispaper proposes the design idea and method of USB device interface IP soft core.First, the system architecture and communication theory of USB1.1 specificationare introduced briefly in this paper, which is the basis of the design andimplementation. Further, the design idea and details of each module in USB deviceinterface IP Core are described. It mainly focuses on physical layer, protocol layerand controller module. The physical layer realizes the separation of clock and data,the conversion of serial signal and parallel signal. The protocol layer, which isdivided into three parts, accomplishes the complexed USB protocol. The controllermodule adopts two methods, special and universal, to complete its function.Finally, the FPGA implementation environment and its verification flow arepresented in this paper. In this process a configured USB mouse correctly finishes thecommunication with host PC. USB transactions between the host PC and USB mouseare monitored and logged successfully by USB bus analyzer. The result of FPGAimplementation indicates that this IP Core is suitable for what is expected and can beused into other USB devices and SOC applications as a single module.