never mind...the .zip has MPHs 2.0 -> 1.5 downgrader in another .zip with instructions sayin its the 2.0 -> 1.5 and the other on says theres an eboort that works with 2.5 ...
root of .zip
...<dir> eboot.zip
......eboot.phb
...instructions.txt
...<dir> MPHDowngrader.zip
......h.bin
......index.dat
......downgrader.txt
......<dir> PSP
..........<dir> Photo
...............<dir>overflow.tif
============
the instructions say
2.5 Downgrader...........(NEW "EBOOT.PHP" CREATED SO IT WORKS WITH 2.5)
Instructions:
Step 1: Connect your PSP to your computer via USB. On your memory stick, create a folder called UPDATE inside /PSP/GAME/ and place the EBOOT.PBP file inside this UPDATE folder (ONLY USE THE "EBOOT.PBP" PROVIDED BY US AS THIS ONE IS BUILT FOR 2.50 SOFTWARE, ANY OTHER ONES WILL JUST NOT WORK).
Step 2: Unzip MPHDowngrader.zip. Drop overflow.tif into your /PSP/PHOTO/ folder. Put both h.bin and index.dat in the root of your Memory Stick.
Step 3: Disconnect your PSP from your computer and plug in the AC adapter.
Step 4: Navigate to Photo then Memory Stick via the PSP’s menu system and start scrolling down through your photos until you reach the overflow.tif picture.
You’ll know you’ve hit it when everything freezes and you get a black screen with a bunch of white text output.
If your PSP freezes without going to this black text screen, then hold the power button for about 10 seconds until the PSP shuts down, then hit the power button again to start it back up. Repeat this step until you get that black screen.
Step 5: Don’t panic. Hold the power button for about 10 seconds until the PSP powers off. Hit the power button again. Your PSP will start up, and if you navigate to your System Information, you’ll discover that your PSP thinks it is running version 1.0 of the firmware. It isn’t and you cannot run homebrew (yet).
Step 6: Navigate to Game—>Memory Stick, hit the X button, and navigate to the 1.5 updater. Make sure you have your PSP plugged in or the upgrade won’t work. Click the X button and update like you normally would. At the end of the upgrade you will receive an error saying that the upgrade failed and to contact Sony. Don’t panic. Ignore this and again force your PSP to power off and reboot.
Step 7: After the PSP reboots you will receive an error screen that is scary and confusing because it is in multiple languages. Don’t panic. Find the language you can understand and read the corresponding line. It notes that your preferences are fragged and that you need only hit the O button to restore some default-ish settings. Hit the O button.
Step 8: The PSP will start back up and you will go through the initial setup like the day when you first bought your PSP. Do so and then go to the system info pane again, where you will see that you are rocking version 1.5. Run homebrew at will.
NOTE:
WHILE THIS METHOD HAS BEEN TESTED AND SHOWN TO WORK FOR MANY PSP USERS ALREADY, THERE IS NO GUARANTEE THAT YOU WONT SCREW UP YOUR PSP BY TRYING TO DOWNGRADE. THERE IS ALSO NO WAY OF TELLING IF THERE WILL BE ANY FUTURE PROBLEM DUE TO DOWNGRADE. IF YOU BREAK YOUR PSP, TOUGH! IT'S NOT MY FAULT AND IT CERTAINLY ISN'T THE FAULT OF MPH EITHER! YOU ARE THE ONE THAT WILL BE DOING THIS, NOBODY ELSE, SO IF YOU DO IT WRONG, OR ANYTHING BAD HAPPENS, IT'S YOUR FAULT!
and the downgrader says....
-> This is has not been tested, it could brick your PSP <-
-> I AM NOT RESPONSABLE FOR EVENTUALS DAMAGES <-
Downgrading 2.00 -> 1.50 method
-------------------------------
Requires :
----------
- PSP 2.00 (if you have an 1.51 or 1.52, update to 2.00)
- The 1.50 EBOOT.PBP update (
http://shockzone.free.fr/PSP/Tool/EBOOT_1.50.zip)
- MPHDowngrader (
http://www.chez.com/mph/)
Installation :
--------------
- Create a UPDATE folder in PSP/GAME/ folder of your memory stick
- Copy EBOOT.PBP (update 1.50) in UPDATE folder
- Unpack MPHDowngrader.zip
- Copy overflow.tif in your PSP/PHOTO/ folder of your memory stick
- Copy h.bin in root of your memory stick
- Copy index.dat in root of your memory stick
- Plug the AC adaptor
Then, enter in VSHELL PHOTO MENU, this will launch Version Changer.
Create an USB connection and if the Version Changer has been installed, a new file is created in your root of your memory stick (ms0:/index.dat.bak).
Then go to VSHELL GAME MENU and launch 1.50 update.
Follow the instructions ...
MPH