使用方法：
引用
This is how I've downgraded my FAT PSP with CF 3.71M33 to 1.50 Original FW:
* Copy the entire content of the attached file to PSP\GAME folder.
* Rename Original FW 1.50 file to UPDATE.PBP and copy it to PSP\GAME\UPDATE folder.
* In the Game menu launch "Update to X.Y.Z."
* Follow the onscreen instruction and it's done in a while.
解压的update文件夹拷贝到PSP/GAME里，把1.5升级文件更名为update.pbp放入update文件夹内
然后在XMB界面运行降级即可！
注意：
这个程序只对应1000系列的老PSP！老P的3.71M33用户降1.5记得把系统语言改成日或英文！不要中文下刷！否则砖头一个！
