GUIDE: How to recover from strange flash0/1 problems.

[over_clox]

!!! WARNING !!! Mucking around with your PSP's internal flash memory can possibly cause it to brick. Even if you follow every instruction here to the letter, this is still a risk we all take when we open that Pandora's Box (a little pun intended) for modification. Although the goal of this process is to repair otherwise unexplainable problems and fix your PSP's flash0/1, problems you may not even really be aware of, it could just as well damage it too, especially if you're not sure what you're doing. I will not be held responsible for any damages that may arise from the (mis)use of this information. Use at your own risk. Be sure to make a backup of whatever firmware you already have working before you start changing anything.


After running into numerous odd problems while attempting to modify my flash0 on my 3.52 M33-4 PSP Phat, I started to notice a theoretical pattern to what was causing the problems. My theory was that the firmware really doesn't like any fragmented files, and may not even like garbage in file slack space. After successfully making and testing a Pandora kit, I felt prepared to start testing different processes on flash0 to attempt to improve on my flaky PSP to which nearly all problems seemed to point to files I had changed and not to much of anything else. I was quite pleased to see that this technique not only worked, but it even fixed unexplainable bugs that had remained from previous firmwares on one of my PSPs. Before I fixed that one, I couldn't even access flash0 unless I accessed the memory stick first, otherwise my PSP would crash, and even worse the problem carried itself through multiple firmware installs of different versions (3.40OE & 3.52M33-4). After this fix, the problem is totally gone, like nothing was ever wrong with it (except the busted UMD drive, different story though).


My complete flash0/1 setup/cleanup/backup process:

1. Install your custom firmware and whatever updates that go along with it. Follow the author's instructions for this.
2. If you didn't have to already, format your flash1 and configure it to your basic liking with only your primary network.
3. Using a homebrew such as PSP Filer, backup your flash0 and flash1 into disk image files (.img) (NOT nand dumps, .bin).
4. Using a disk imaging program like WinImage, open each image and click Image>Defragment Current Image, then save the files.
5. Close WinImage, start recovery mode on your PSP, connect flash0/1, and reopen WinImage (just the program, no files now).
6. In WinImage, click Disk>Restore Virtual Hard Disk image on physical drive, select your PSP from the list, and click OK.
7. Select All Files, find your newly defragmened flash0/1 file you wish to restore, open it, and select Yes to any prompts.
8. (Optional) You may wish to redump your flash0/1 afterwards and use these redumps as your backups. I kinda recommend it.

That's it! If you don't feel like folloing optional step 8, you can use the defragged images made in step 4 as your backup.


What does it do special that defrag doesn't? Since WinImage rebuilds the image file from scratch, it defrags all the files and nulls out all file slack space. Normal defragmentation has to keep all data on the volume at all times to avoid potential data loss from a power outage, and so is incapable of wiping out file slack space, plus directly defragmenting a flash volume puts undue stress on it, and it will eventually wear out if written to too much. Whether this minute null slack space detail is important to guaranteed stable operation of the PSP is still unknown to me, but it does guarantee that there is absolutely no questionable extra garbage information still remaining on the flash between the files, and that all the files are in single solid pieces. Everything else gets zeroed out and put into one contiguous block of free space, and with the extra blocks of zeros in the image file, it'll compress a couple of megabytes or so better too. I know mine did, which just proves how much extra garbage can remain from previous file contents long ago flashed over or erased.

Of course, this process depends on being able to make a .img dump of your flash, open it on a PC, defragment it, and restore that over your current flash. That's the basic process in a nutshell. I do realize that PSP Filer only allows flash maintenance in the 1.50 kernel version, which may complicate things for slim/lite owners, but I hope that everyone is able to make good use of this information and find (or make if necessary) equivalent homebrew for the slim/lite series to generate the proper flash dumps for this process to work. Come to think of it, this also suggests the idea of a homebrew PSP flash defrag utility. I'm sure it probably never crossed anyone's mind before, but it seems very useful now, knowing now that it can actually fix problems. Everything can be done on the memory stick and in RAM before any changes are made to the real deal. I would consider making such a utility myself if I was deep into homebrew coding, but I'm not and I'm tossing the idea out in the wind to see where it blows.


So far, I've had 100% success out of this technique, but that's only between the two phats I own right now. If this process somehow helps you out of a jam too, or you have relevant information on the slim/lite, then by all means, share your findings with the rest of the commmunity.


BTW, here are some other various PSP hints from my experience:

1. Do NOT format your memory stick in Windows when connected through PSP Filer, unless you want a bricked "2TB" memory stick.
To recover from such a brick, you must format using a separate card reader because the PSP has no idea what to do with it.
2. Do NOT charge your battery using a piece of a busted PSP motherboard, unless you want a bricked battery (trust me on this)
Recovery: you'll need some luck, a piece of wire, and about 30 seconds of shorting the + and - battery terminals together.
3. Avoid UCES90027.zip (Go!Edit for PSP Camera). I don't know why, but it bricked my PSP the first time I tried to use it.
4. PSP Camera will not work on CFW 3.52M33-4 unless the default kernel is 1.50. This may hold true for other versions too.
5. Faster 4GB or less MS Pro: backup everything, reformat with Windows from USB mode in XMB as FAT16, and restore backups.
6. PSPWOL (Wake On Lan), contrary to the readme, does NOT need the computer's IP address, the WOL packet just uses the MAC.
7. A PSP can be used to boot a PC from the memory stick, with the right technical skills required to set that up of course.
8. It's really easy to turn the PSP into a crude flashlight. Just make a 480x272 solid white image and put it in your photos.
9. If you haven't stumbled on this homebrew yet, find it and try AntiTetris. At least look it up on YouTube, you'll trip out.