Working PSP Firmware 2.0 to 1.50 Downgrader!!!
Although this has been tried and found working, this does not mean there is no risk involved so use at your own risk.
Steps to use the MPH downgrader:
– Create an UPDATE folder in the /PSP/GAME/ folder of your memory stick
– Copy EBOOT.PBP (update 1.50) in /PSP/GAME/UPDATE folder
– Unpack MPHDowngrader.zip
– Copy overflow.tif in your /PSP/PHOTO/ folder of your memory stick
– Copy h.bin to root of your memory stick (meaning in ms0:/)
– Copy index.dat in root of your memory stick (meaning in ms0:/ as well)
– Plug the AC adaptor
You memory stick filesystem should look like this (where X is your memory sticks directory):
X:/PSP/PHOTO/overflow.tif (with no other pictures in there)
X:/PSP/GAME/UPDATE/EBOOT.PBP (the 1.50 Firmware update eboot)
What you do next is go into the Photo Menu on the PSP and it will show some jumbled text, which is normal. Wait about 30 seconds and then restart your PSP.
From there you will now have a new file in your PSP’s root directory called ms0:/index.dat.bak. In the next step you will go to your Game Menu, Then Memory Stick, and then Launch “PSP Update ver 1.50.”
It will then ask you if you really want to downgrade and then lead you along to the actual installing. Here is where I got scared. It installed to 99% then errored. This is OK. Restart your PSP and turn it back on. It will come up with another error which is OK as well. Restart it again and you will have PSP firmware version 1.50, and it will lead you through setting up language and time etc. Enjoy, and welcome to the world of legal homebrew, not piracy.
終於可以玩《GUNDAM BATTLE TACTICS》，呵呵～