My 6th downgrader idea

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!

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)

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...

Quote:

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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.

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

Quote:

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Disclaimer:

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

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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.

Quote:

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Originally Posted by Fanjita

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

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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.

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...

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.

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!

I would try this if only I had a 2nd memory stick. I will probably get one after Christmas though, but I guess someone will have tried this by then :(

Just realised my wife's phone has a memory stick duo in it. Need to charge the psp a bit then will try :)

It said "The update failed. The memory stick was removed." Can this be hacked in the updater program so that the memory stick removal doesn't trigger this?

If anything could be hacked in the update program we'd have a lot cooler stuff than downgraders :)

I am racking my brain for possible ideas.

Still thinking...

Still thinking...

OK! Can anyone give me that bogus 1.00 update if they can find it?

i thought of another idea

What if someone made an index.dat that could not be overwritten, so when the PSP updated, the file would be the same? i.e. I have version 1.50, use a version changer to change to permanent 1.00, update to 2.50, still thinks it is 1.00, downgrade with 1.50 update.

What do you all think?

I think we should wait and see what happens with the GTA exploit soon.

i thought of another idea

What if someone made an index.dat that could not be overwritten, so when the PSP updated, the file would be the same? i.e. I have version 1.50, use a version changer to change to permanent 1.00, update to 2.50, still thinks it is 1.00, downgrade with 1.50 update.

What do you all think?

nice! make the index.dat not be able to be overwritten by encrypting it or somthing
?

Man I am so tempted with this, has anybody tried it? it's been 10 days since this was posted.

The INDEX.DAT file is already marked as read-only by the system, which write-enables it during upgrade.

So, nice idea, but I don't think it can work.

I meant the swap trick. anybody been brave enough to do that? or is that a dead duck now..

I have had ideas towards the Mem stick swap thing. I have come up with some stuff that I haven't tried yet. Will try now

I've got it! I thought of a sure-fire way to downgrade any version, but the procedures are impossible without the hard drive.

If someone had the 4GB hard drive, they could boot the update, open the hard drive, remove the drive, replace it with the Compact Flash card with the 2.60 update with the DATA.PSAR from the 1.50 update, and continue the update!

If that was guaranteed to work i'd buy a hard drive TODAY

id try this stuff but my psps warrenty doesint cover software falure! :(

i love reading your ideas indian cheese.. more interesting than most other ideas i have read.
makes me wanna buy another psp just so i can play around testing these things...
dunno why tho, cos ive never updated my 1.0 psp :p

i got 2.01 and i spent all my xmas money to get it and i am not gutsy enuff to **** around with it, im sorry

good idea

I'm not going to even attempt any of your crazy ideas until Fanjita responds to it. No offense to you IndianCheese, but Fanjita is a PSP GENIUS! Everything else you thought of hasn't worked and Fanjita knew exactly how and why it didn't/wouldn't. I wish he would try to make one...

mabye that could work. I just got my 1.5 motherboard though so there is no way im ever gonna update it!

1.5 is sooo cool!

By the way. i had 2.6 previously

Quote:

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Originally Posted by IndianCheese

I've got it! I thought of a sure-fire way to downgrade any version, but the procedures are impossible without the hard drive.

If someone had the 4GB hard drive, they could boot the update, open the hard drive, remove the drive, replace it with the Compact Flash card with the 2.60 update with the DATA.PSAR from the 1.50 update, and continue the update!

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I think you have done it! Does anyone have the 4gb hard drive to test this?

The way I see it, the PSP only senses when the Memory Stick is removed, not if the data is changed. So, this could possibly work with the 4GB hard drive OR the 4-in-1 NEO pad thing that supports Memory Sticks, SD cards, MMC card, etc. and take out the card being used. Maybe the PSP wouldn't recognize that the pass-through Memory Stick Duo dongle that was part of the 4-in-1 was still connected, but there was no data in it because there were no cards inserted into it. That way you could switch the update files without disassembling anything.

Also, this method only works on downgrading any version below the current version (i.e. 2.70 update can be run on 2.60 and below, so it would work, but there is no update above 2.70 to run/edit with 1.50 psar.)

1 more thing: The risk of bricking is VERY high, because in reality, you are updating to 1.50 via the flashing program of a 2.60/2.70 update. So there you have it!

Quote:

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Originally Posted by IndianCheese

The way I see it, the PSP only senses when the Memory Stick is removed, not if the data is changed. So, this could possibly work with the 4GB hard drive OR the 4-in-1 NEO pad thing that supports Memory Sticks, SD cards, MMC card, etc. and take out the card being used. Maybe the PSP wouldn't recognize that the pass-through Memory Stick Duo dongle that was part of the 4-in-1 was still connected, but there was no data in it because there were no cards inserted into it. That way you could switch the update files without disassembling anything.

Also, this method only works on downgrading any version below the current version (i.e. 2.70 update can be run on 2.60 and below, so it would work, but there is no update above 2.70 to run/edit with 1.50 psar.)

1 more thing: The risk of bricking is VERY high, because in reality, you are updating to 1.50 via the flashing program of a 2.60/2.70 update. So there you have it!

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Not bad idea. Hard to say if it would work though. Like you said this method has a high likelyhood of bricking your PSP.

Quote:

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Originally Posted by IndianCheese

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!

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Not going to work. I have tried this idea extensively last year when I mistakenly updated to 1.51 and wanted the homebrew abilities of 1.50.

Changing ANY information in the Updates makes there AES signatures void, and thus they will not run.

As well, there is a data check. The Updater protocol doesn't just look at the PARA.SFO for the version. It apparently looks at the data inside the EBOOT and see if it matches the data already in the flash.

If it matches, or is older than the data in the flash, it does not continue.

Sony obviously patched up the Updater protocol very tightly, since the consequences that can occur due to an error are fatal to the PSP.

Trust me, the Updater-swap route is a failure. It will not work.

Quote:

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Originally Posted by F9zDark

Not going to work. I have tried this idea extensively last year when I mistakenly updated to 1.51 and wanted the homebrew abilities of 1.50.

Changing ANY information in the Updates makes there AES signatures void, and thus they will not run.

As well, there is a data check. The Updater protocol doesn't just look at the PARA.SFO for the version. It apparently looks at the data inside the EBOOT and see if it matches the data already in the flash.

If it matches, or is older than the data in the flash, it does not continue.

Sony obviously patched up the Updater protocol very tightly, since the consequences that can occur due to an error are fatal to the PSP.

Trust me, the Updater-swap route is a failure. It will not work.

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He already said swapping memory sticks won't work.

Apparently not, since thats the motives behind his Neo4-in-1 idea above...

Again, trying to hack through the updater protocol WILL NOT work. Sony took extra care in ensuring that this is air tight. A simple bug in the Updater protocol could essentially brick 1000s of PSPs and Sony would be dealing with a Class Action Lawsuit.

Just give it up; you're ideas have been tried extensively last year. The PSP checks other sources to ensure the data is legit, not just the SFO.