Dark_Alex Mathieulh and Yoshihiro now say they have a final working PSP downgrader. Remember this is a very risky process and there are no guarantees, so if you end up with a bricked PSP don't say you weren't warned!
Instruction for the 1.50 user
1) Copy the folders downhelper and downhelper% from the folder 1.50 HELPER folder to
/PSP/GAME/ in your memstick.
2) Obtain the 1.50 updater and put it in /PSP/GAME/UPDATE in your memstick.
3) Init the downhelper program.
It will dump your flash and some files from the updater eboot to the memstick.
4) After that, the program will exit. You can now delete the updater from /PSP/GAME/UPDATE
5) You'll notice that you have a new folder in the root of your memstick called "DOWNDATER".
That's the folder you'll have to send to a 2.50/2.60 to let him test the downgrade.
Instructions for the 2.50/2.60 user
1) Copy the folder the DOWNGRADER/2.50/DOWNDATERTEST if you have 2.50
or DOWNGRADER/2.60/DOWNDATERTEST if you have 2.60 to /PSP/GAME/ in your memstick
2) Wait someone with 1.50 to pass you a folder called DOWNDATER and copy it to the root of your memstick.
3) Init gta and the eLoader
4) In the eLoader menu, choose the downdater test. WARNING: the program won't output any display
and any warnings, it will init the downgrader process inmediatelly.
5) You'll see the your memstick flashing. That means that your psp is being flashed from the memstick.
You won't see any type of output in the screen (this is for safety). When the memstick finishes of
flashing, WAIT at least a minute, and then reinit your psp by holding the power button.
6) That's all. If all went right, you'll have 1.50. If it went less good, you'll still have
2.50/2.60. If all went wrong, you'll have a bricked psp(except in the case you have
the modchip) Remember that you have accepted that risk.
Technical Details
This program performs the following operations.
- It loads the ipl_update.prx and lflash_fatfmt.prx from the 1.50 updater.
- It performs a logical format of the flash0 partition using the function
sceLflashFatfmtStartFatfmt found in the lflash_fatfmt.prx
UPDATE (0.5): now it doesn't use the logical format. It was one of the causes that make this
not to work.
- It writes a dump of the 1.50 flash0 to the flash0.
- It writes the Initial Program Loader (Ipl) using the functions sceIplUpdateClearIpl
and sceIplUpdateSetIpl from the ipl_update.prx module. The ipl is embedded in that module.
Other Considerations
- Users with TA-082 psp's shouldn try this. Also, it may be better that at the beginning, only users
with a 2.50/2.60 NOT from factory (they updated from a below firmware) try this.
Quote:
As you already probably know, these days I have been coding with Mathieulh and Yoshihiro a downgrader for 2.50/2.60 that has been finally confirmed working yesterday/today.
I would like to thank to:
- hitchhikr / Neural for finding the kernel mode exploit
- Mathieulh & Yoshihiro for helping me to create this
- Edison Carter/Fanjita for the GTA exploit and the eLoader respectivaly.
- All the people from EOL and other forums that supported me
- All the people that risked their psp's for the tests to make advance the PSP scene.
I might buy a new one for this. I have a 1.5 but the blur on all these early models is beyond terrible. Its still pretty bad on new models, but they have definately decreased it a whole lot.
This day will remain in history...
Great work Dark_AleX, Mathieulh and Yoshihiro..
I already have a "virgin" 1.50 PSP, but still, it's great that almost everyone can soon enjoy homebrew, even without the modchip..
I hope this will also bring down U.P.'s price a bit...
Congrats for getting this working..
- Users with TA-082 psp's shouldn try this. Also, it may be better that at the beginning, only users
with a 2.50/2.60 NOT from factory (they updated from a below firmware) try this.
Quote:
Originally Posted by _stryder_
antastic news for 2.xx psp owners! i still own a 1.5 but my gf wants homebrew! so now i'll have to buy her a 2.6!!
whats the difference between TA-082 psp (and how can you see you have one)
and a factory psp and why can't you use those???
****, I had a 1.5 PSP, exchanged it for dead pixels, got a 2.01 PSP... gave up hope and upgraded to 2.7 to play the Loco Roco demo.
I guess I won't upgrade again and hope that once the modchip comes out and people can test more firmware flashers, etc, they can find a 2.7 downgrader.
PSP - 
Linear Mode
