1.5-1.0 Downgrader

**F9zDark** · July 6th, 2006, 22:31

Originally Posted by Blazed247

well first off how much more security does 1.5 have than 1.0(which has no security at all)? i mean i know u'll have no corrupted data and no security but is that it?

1.5 has AES encryption methods, which protects Sony's interests by not allowing unsigned(unencrypted) code from running.

However, the folder naming convention SNES, SNES%, along with a special eboot file, somehow circumvents the AES signature check.

1.0 doesn't even have AES present, therefore any code can be executed.

Sometimes I think Sony purposely left AES out of 1.0 so that the Japanese would be allowed to have homebrew all to themselves. (Because it is a really HUGE oversight to have missed putting in a feature so paramount to the PSP; given the fact that Sony doesn't even give out the AES signature to anyone.)

About the downgrader, I suppose it isn't as bad as I once thought. Having the ability to downgrade to 1.0 will see a huge increase in homebrew developed for 1.0, since developers who have 2 PSPs, can no downgrade to 1.0 on one of them and use 1.5 on the other and make sure a program runs flawlessly on both.

**F9zDark** · July 6th, 2006, 22:35

Originally Posted by jason867

I just upgraded back to 1.5 using a U.S. 1.5 update firmware.

Everything appears to be the way it should, except for one thing, the [X] [O] buttons didn't switch back to normal.

Before I did anything, [X] would select and [O] would go back

But after downgrading to 1.0, and upgrading back to 1.5 the buttons are still switched ( [O] selects, [X] goes back )

I know this isn't a big deal, and probably could be changed easily via some flash alteration using flashmod or something, but I'm not sure if anyone has offered that yet.

But it's still enough to bug me, I'm used to it being the other way.

Anyone have any ideas on how to fix this?

And by the way, in a lot of japanese anime, dead/unconsious characters often have their eyes X-ed out to indicate so. Not only that but in cartoons, alcoholic beverages also tend to be labeled with "xxx" This might have something to do with the buttons being switched on japanese firmwares. Just a though...

Did you use US 1.5? I think that might make a difference.

Also, I believe X-Flash can fix it. Or PSPset. Be careful though, writing to flash can brick a PSP, so use at your own risk.

**AuroEdge** · July 6th, 2006, 23:13

I don't know if it's already been mentioned, but with v1.00 firmware you are able to modify the official firmware however you want pretty much. Also, you can load custom firmware. Now, good custom firmware is a ways off but I see custom firmware as the best step forward now instead of always trying to sidestep Sony. Granted you'll still have to update the firmware whenever Sony releases games that require a new firmware version BUT you won't have to wait another year before some little exploit is discovered.

**pkmaximum** · July 6th, 2006, 23:45

True to me the downgrader willl just be worth it in general if dev hook (the legal version) works on 1.0 firmware. Has anybody actually tried though using PSP Brew to convert it to a 1.0 eboot then trying to just execute it because I believe that will work just fine. But perhaps not as that should of already been though of way back. Well maybe dark alex or the creators of dev hook will get to work on that, because I'm most interested in dev hook as its one of the best applications on my PSP.

**mog** · July 7th, 2006, 01:09

Originally Posted by pkmaximum

True to me the downgrader willl just be worth it in general if dev hook (the legal version) works on 1.0 firmware. Has anybody actually tried though using PSP Brew to convert it to a 1.0 eboot then trying to just execute it because I believe that will work just fine. But perhaps not as that should of already been though of way back. Well maybe dark alex or the creators of dev hook will get to work on that, because I'm most interested in dev hook as its one of the best applications on my PSP.

pk, it doesn't work quite like that... I think it's more to do with needing the prx files from 1.50 fw due to how the loader is coded.

Booster himself had mentioned in one of the Devhook 0.41 releases something to test on a 1.00 PSP.
That test was to use 1.50 prx's instead of 1.00 for the ones that cause problems i think.
If that did fix the problem, then it will also likely fix other loaders like mph's aswell.

I will try that test if I buy a game that won't run without a umd loader.
But i'm sure someone else must have tested that by now...
What's good is that booster will now be able to downdate to 1.00 to try it out himself if he wants.
I'm sure we will see all UMD loaders working on 1.00 in no time at all.

Also, for people that keep saying there are many 1.50 homebrews but few 1.00 homebrews...
As far as I've noticed, every homebrew app works on 1.00 except ones that deal with flash emulation (umd loaders) or modifying (x-flash).
These things only don't work because they are written specific to fw 1.50; not because 1.00 is incapable of such things.

**pkmaximum** · July 7th, 2006, 02:03

Yes I had a feeling that converting the 1.5 eboots to a 1.0 eboot would not work because of certain firmware contents from the 1.5 firmware. Its just I did not see anyone actually mention even after converting the eboots it still not working so I figured I would post for someone to try it out for test results. I was almost 100% postivie that it was not going to work anyway but still I figured it would be best to find out. Well I guess we can only hope down the road that this problem will be resolved because dev hook is one of the most important apps for the PSP.

**1_Man_Matrix** · July 7th, 2006, 03:26

I'm looking for a confimation on something...
And seeing as 1.0 and 1.5 can help to toy with clock frequency, I might find it here... hehe

I have Tomb Raider UMD, and I can't play it now I've downgraded to 1.5, Devhook won't run it, etc. But I did get pretty far before I downgraded.

It's a pretty good game, my main complaint is the chuggy FPS, it's the only thing that I can notice that brings any sort of dismay to it.
So I was wondering if I kicked it up to 333mhz, if it would help make things a little bit smoother. I did it to GTA with EC cheat device, but GTA already ran quite well, but I did notice an improvement.
So anyway, Is there a way to run TR:L UMD on 1.00? or 1.50?
Or, is there yet a way to kick up the clock to 333mhz, then run TR:L on 2.6?
I can't think of any off the top of my head...

Thanks chums

P.S: Worth downgrading to 1.00? anything exponentially different from 1.50? I got Ultimate Doom, Doom 2, Plutonia and TNT running, so I'm happy

**jason867** · July 7th, 2006, 05:35

I got my buttons switched back to normal by accident. I tried resetting the psp to factory settings, but that didn't fix it.

I upgraded from 1.5 (that was a U.S. 1.5 btw) to 2.0 for certain reasons, which didn't fix the buttons either. But then I downgraded back to 1.5 using the older tiff exploit method, and after going through the blue screen where it tells you to reset your psp to factory settings in multiple languages, my buttons were fixed back to normal. And I have experienced flawless operation of my 1.5 psp since.

Lol, my psp firmware has been doing jumping jacks (1.5 -> 1.0 -> 1.5 -> 2.0 -> 1.5) Not counting all of the other times I've messed with the flash...

The homebrew I tried using in 1.0 was just a small graphical thing I programmed myself that I happened to have a single eboot handily available. I stuck it in a GAME/folder and tried running it. After pressing [X] the gameboot.pmf video immediately started playing and the game started immediately afterward. No pausing no nothing...

Also for some reason Twisted Metal: Head-On & Legend of Heroes both played fine. I thought they both required 1.5 to run?...

Anyways I say thanks to the coders who came up with this, your work is deeply appreciated, although for now I'm staying 1.5.

**PSPegasus** · July 7th, 2006, 08:07

This sounds very, very interesting. But at the moment I can't see any real benefit to downgrading to 1.0 from 1.5. Most homebrew is written for 1.5 anyway, so 1.0 is kind of a fun thing to do, but not really useful as yet. So I'm sticking with 1.5 for now. When people start releasing really awesome stuff that's 1.0 specific (eg. custom firmware), then I'll think about it.
Are there any drawbacks to the 1.0 firmware? Like is it incapable of reading files or memory sticks over a certain size?