所谓固件，就是存储在程序内存中的程序,用以完成驱动程序无法完成的USB 芯片及外围芯片的初始化及控制工作[23]。USB固件程序设计是USB接口部分的主要工作，它的主要目的是：当USB设备连接到主机上时，主机可以发现新设备，然后建立连接并完成数据传输任务，也就是能够让Windows正常检测和识别USB设备。因此在USB固件程序中，最重要的工作就是USB描述符的定义和USB传输中断的处理。-called firmware is stored in the memory of the procedure, Drivers used to complete the impossible chip and external USB chip initialization and control work [23]. USB firmware design is USB major part of the work, its main objectives are : When USB devices connected to the host, the host can be found in new equipment, then establish a connection and data transmission to complete tasks, is to let the normal Windows USB detection and identification equipment. Therefore USB firmware procedures, the most important work is described USB define and USB transmission interruption of treatment.