The Hardware Circuit Design And Implement Of The USB Device Controller

Universal Serial Bus, or USB, is a new bus interface technology. Since 1996, USB-IF (USB Implementer Forum) announced an agreement USB1.0, it has developed rapidly. After upgrading to USB2.0, companies such as Intel announced an agreement of USB3.0 in the November 2008.At present, the USB functional controller of the device controller on the market always use a microcontroller to realize, but in practical application, the function of the functional controller can also use a similar approach the hardware to realize. Although the approach would due to its host of equipment, which related to the complexity of the enumeration process, and therefore the structure would be design relatively complicated, but the use of hardware circuits can be realized to enhance the integrated USB device controller, and to accelerate the USB device controller of the processing speed. Further, because it does not have to use its microprocessors, so it achieves lower costs.This article is based on the basis of the above analysis, a USB2.0 based on the full-speed USB device controller hardware and design of the full realization of the program. Through a careful analysis of the transfer principle and USB communication protocols, and research of the physical structure modules of the overall controller constitute USB device. In order to achieve its function, it is divided into several major components: transceiver, protocol layer, data and functions of the buffer control module, and then used the process of Top-Down approach and the modular Verilog HDL language used to achieve the full speed USB device controller of the entire digital logic circuit design. Next, this article also states Modelsim simulation software using USB device controller for each module to achieve a simulation of its response to the host through the enumeration process of analysis that can shorten its response time and increase processing speed communications correctness. Finally, this paper also uses the synthesis tool Synplify to make a comprehensive analysis of the design, at last gives a conclusion.In this paper, compared to other similar USB device controller, the USB device controller design has its advantages and innovations in the control data in the transmission and reception. Moreover, the addition to achieve high speed and low cost advantages, because of its hardware circuits instead of the micro-controller and, therefore, it needn't to design protocol layer and the interface circuit between the MCU and the need for transmission between the control and status register group signals designed to reduce to some extent, which would make the design more difficult. The whole design of this article integrated USB device controller, high speed and low cost, at the same time there can be extended in line with today's digital circuit, which is the development of the requirements of USB device controller.