这是一个测试MP3的程序，通过USB口来测试此款MP3是否出现了功能故障,或者此MP3是否是出厂状态，实现了从PC上层直接控制下层硬件的范例.-This is a test MP3 procedure for the adoption of USB MP3 Photo Player to test whether there is a functional fault, or whether this is manufactured MP3 state, from the PC to achie