该文档里面详细说明了USB设备标准请求的格式及各类请求的编号,同时详细解释了所有的标准请求,还包含了常用的描述符的格式及各字段详细说明,额外增加了HID描述符等(The document details the format of the USB device standard request and the number of various requests, and explains all the standard requests in detail. It also includes