FPGA Implementation Of USB Interface Based On UPLI Protocol

In recent years, because the body feeling input started the third revolution in human computer interaction technology, and has great market value, so the body feeling input technology research more and more people, companies also follow up quickly. Somatosensory input technology is the core of pattern recognition technology, involving a large amount of image algorithm, We use the solution is to match the FPGA and ARM, using FPGA parallel processing speed and the ARM of the advantage of the special image processing algorithm, to implement the somatosensory input signal pattern recognition.In the somatosensory input device in the process of the transition, between the ARM and FPGA, FPGA and the need for interaction between upper machine a large amount of data, so it need a standard data bus interface, to facilitate the transport between the two, improve the transmission efficiency, and convenient maintenance. USB bus technology with its in real time, communication speed, reliability and other advantages, the current has been widely used in business and mature. So in the FPGA communication with the outside world also use the USB protocol.This paper is aimed at the ULPI agreement in USB protocol, gives the hardware circuit and the FPGA implementation solution. First of all, introduce the function of USB devices, bus topology structure and electrical physical properties. Then analyses the ULPI protocol specification, ULPI interface signal and working mode, and introduces the ULPI PHY chip, at the same time simply illustrates the related hardware platform. Finally discusses how the FPGA implementation ULPI agreement, and the analysis of each function module. And from the beginning of the device enumeration, each module is described in detail the specific work process.Now this system has been applied in practical engineering, the test results show that the scheme makes the data communication transmission stability, high efficiency. Late because it is pure logic design, can also be used for the production, to meet the actual demand in the project. Interface of USB device FPGA implementation with Soc integration has guidance and reference significance.