Possible hybrid firmware

Someone may be able to use this info to his or her advantage...I made a discovery today. You can go through the step by step below to see what I saw. NOTE: You will need the 2.00 firmware installed to do this.

1. Place a picture as your background
2. Downgrade
3. Install File Assistant ++
4. Run File Assistant ++
5. Go to the directory "flash1:\vsh\theme" and open the file in that folder.

Surprised? I was too. That means that the 2.00 files are still present on the flash, but the OS menu, which was changed with the 1.50 update, is not showing the 2.00 options. If someone could find the 2.00 OS menu files and create a patcher to replace the OS menu on 1.50 with the one from the 2.00 firmware, the internet browser, backgrounds, and AVC video would be available with homebrew support. I think it sounds like an idea.

You know what else? I bet if you look in your registry in Windows that you'll see registry keys from software that you've uninstalled before!
Shocking!
They're called "remnants". You do NOT have a hybrid firmware. It's just leftover files.
Since nothing in the 1.5 "update" ever wrote to that directory, then it's not going to "remove" it or write over it. The flash in the PSP isn't like that of a router or something, where you flash a new firmware and it completely obliterates everything else in the flash by writing over it.

i found that and it surprised me and it does mean some parts of the firmware are still there and in theory you could create a a hybrid firmware

Not if 1.5 doesn't "know" about anything from 2.0 that's required to run a 2.0-specific game. Especially the encryption keys.

Remember the "new updates contain the old ones" quote? The 1.50 update was created BEFORE the 2.00 (wow! unbeliveable!), so the update merely writes to the flash. It does not remove the files from the 2.00 update. The only 2.00 thing that the 1.50 update overwrites is the OS menu. If you have downgraded, the web browser is still in your flash, but it is not accessable because the 1.50 OS menu is being shown. If the 2.00 menu was imported into the downgraded 1.50 PSP, the Network icon would be visible, and since the web browser is still present on your flash (since it was not deleted by the update), you would be able to run it. Now do you understand what I am getting to? The background picture was not deleted because the 1.50 update did not contain the data to tell the system to delete it; if that is the case, then ALL of the files found on 2.00 would still be on the 1.50 system because they weren't deleted by the update.

Settle down, Beavis. The menu is OVERWRITTEN. Any "network code" from 2.0 would also be overwritten by the 1.5 "downgrade" since they are probably using the same filenames, which would explain why you DON'T see the web browser icon and the browser code is not "left behind".

Yep,

I agree with Buthead (iball). The files are just leftover stuff since installing 1.5 won't delete aything from the mem stick. As for the flash (i.e. the good stuff where your 2.0 based junk would be), it was all overwritten by 1.5.

Garak