这个代码需要有一定基础的开发者阅读，特别是对如何识别USB设备及USB基本原理有一定了解的开发者比较适用。程序主要演示了如何编写高层应用与USB接口通信。-This code need to have some basis for the development of reading, especially on how to identify the USB device and USB have a certain understanding of the basic principles