这个程序是本人对周立功的ARM 2200实验板开发的USB固件程序的第一部分，已能实现对USB的枚举，PC能识别USB设备了！其余的功能各位可以自行增加！-this procedure is my right, who ARM Week 2200 Experimental board USB firmware development process to the first part, has been able to achieve USB enumeration, the PC can re