My 6th downgrader idea

**IndianCheese** · December 7th, 2005, 03:43

Requires:

PBP Unpacker
2 Memory Sticks
2.01 or 2.50 PSP
2.60 Update
1.50 Update

Instructions:

Copy 2.60 update PBP. Place into first Memory Stick. Open PBP Unpacker. Extract files from 2.60 update. Extract files from 1.50 update. Create new PBP with 2.60 icon0.png, param.sfo, data.psp, and 1.50 data.psar. Save as update on second Memory Stick. Insert first Memory Stick into PSP. Run 2.60 update. Follow instructions. When screen displays the message that says to press the left arrow on D-pad to begin updating, remove Memory Stick and insert second one. Press left arrow. After update, error should be displayed. When PSP starts, corrupted settings error should be displayed. Restart again for 1.50.

Explanation:

I heard something like this failed before, but there was one difference; only one Memory Stick. The PBP didn't even run let alone update. As can be seen with any homebrew program, when the Memory Stick is removed, the program continues running. So I figure that if the update is already running and the second Memory Stick is inserted that has the same update data on it EXCEPT for the actual update files (data.psar), the program will read from the 1.50 data.psar and copy them to the flash. The only way this wouldn't work is if Sony developed a checksum that, once again, checks the data.psar file to see if it is the right one for the specific update WHILE THE PROGRAM IS RUNNING. We all know it checks when the update is first executed; what about while it is running. No PBP boot problems at all. The valid PBP will have already be booted.

Disclaimer:

I AIN'T PAYIN' FO' YO' BROKEN PSP IF IT DON'T WORK, YO!

***o*** · December 7th, 2005, 05:41

please be sure of this!

i suggest posting this at pspcrazy.com they will be interested (they are much bigger on hardcore hacking over there)

**hiphoplsr** · December 7th, 2005, 15:25

indiancheese, this is probably the best of your ideas you've had yet... id love to test this for you; but im one of those who used the MPH downgrader a few months ago to go from what WAS the uncrackable 2.0 to my cherished 1.5 :P....

keep on keepin on...

**Fanjita** · December 7th, 2005, 18:06

Originally Posted by IndianCheese

The only way this wouldn't work is if Sony developed a checksum that, once again, checks the data.psar file to see if it is the right one for the specific update WHILE THE PROGRAM IS RUNNING.

Or if the data had already been loaded into RAM before running it...

Disclaimer:

I AIN'T PAYIN' FO' YO' BROKEN PSP IF IT DON'T WORK, YO!

Why not have the balls to test your own ideas? Sorry if that sounds tetchy, but I'm getting tired of seeing so many 'downgraders' where the creator doesn't even have the confidence to test it themselves.

**IndianCheese** · December 7th, 2005, 20:25

Originally Posted by Fanjita

Or if the data had already been loaded into RAM before running it...

Well, if you notice, when the PSP is updating, the Memory Stick light flashes, and since nothing is being written to the Memory Stick, it must be reading it directly from the Memory Stick.

**IndianCheese** · December 7th, 2005, 20:32

BTW, the reason that this would not work for 2.60 is (obviously!) because the update file's PARAM.SFO file will only be valid if it is directly from Sony. Want proof? Try changing the numbers 1.50 in the 1.50 update to 3.00 and try updating. It just won't work. So if the DATA.PSP is already loaded from the 2.60 update (because 2.60 is the only version higher than 2.50), there is no need for any version number editing. The PSP will think it is updating to 2.60 when in fact it is updating with the DATA.PSAR from 1.50.

If this would work, it could also work to downdate to 1.00...

**mekajiki** · December 9th, 2005, 19:17

I would totally test this(and I really have the urge to) but my PSP is 2.60.

I was just using it as a normal PSP without homebrew or anything, but I want to play Kingdom Hearts: Chain of Memories and don't want to buy a GBA, so I started looking around and realized that I can't on 2.60 and so far there are no downgraders for it.

Maybe when the next update comes I can use this to try on my 2.60.

**YourStillWithMe** · December 9th, 2005, 20:53

Good idea, I don't have the balls to try this though and I'll flat out admit it. (I have 2 psp's-One to keep at 1.5 FOREVER other-if nesseccary-update but if not kep that at 2.00 with the new psp set to play GTA forever and simple 2.00 homebrew!