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Pikoro · Joined: 13 Jan 2005 Posts: 56

Has anyone had a looksee at what's going on when the psp is first turned on?

The psp, when first turned on, access the memory stick for about 1.5 seconds before actually booting to the firmware's opening screen.

Could it be looking for a diagnostic program on the memory stick? perhaps something that only sony has? Some kind of failsafe flash loader?

I'm just tossing ideas around here, but is there a way to tap into the memory stick and see what the psp is looking for?

perhaps a "boot loader" could be written that would be run when the psp is first turned on. Finding out what the PSP is looking for would be a first step to seeing what might happen no?

If that's the case, there might be a certain folder that gets accessed that we could try dumping a file with the "bootable" flag set to 1?

Just an idea.

Cheers

Erant · Joined: 13 May 2005 Posts: 33

I've already discussed this idea earlier, and it is a good idea, but the actual execution might be a problem. I think it to be a good idea because it's really looking for something, not just confirming that there's a memorystick in there, because it does that when booting the GUI. (The memstick icons won't show up at first, only after some slight memstick activity). In order to execute this, you'd have to have one of those Memstick to Memstick Duo converters, and tap the lines into an FPGA or a digital multi-channel oscilloscope. And I have neither...
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th0mas · Joined: 24 Apr 2005 Posts: 43 Location: Canada

Examining the bootstrap code would be the only way to know what it's looking for.

I have a related question.

On the flash0/1 filesystems, there are portions of the kernel that are encrypted.

Wouldn't these modules be loaded in readable RAM in the userspace (as they are callable kernel calls)?

(in other words we could obtain the decrypted modules, providing a better insight, by copying from RAM instead of dumping from the flash)
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mrbrown · Joined: 17 Jan 2004 Posts: 1536

mrbrown · Joined: 17 Jan 2004 Posts: 1536

mrbrown · Joined: 17 Jan 2004 Posts: 1536

Ok, I've had enough of these empty posts with idle speculation and no research. It adds no new or useful information, and it doesn't get you cool points or whatever (I think I've said this before). From now on I'm moving such posts out of PSP Development into General or Off-topic. If it's redundant it gets locked.

Moved.

mrbrown · Joined: 17 Jan 2004 Posts: 1536

Moved to it's rightful place on the exploit board.

jimmygoon · Joined: 26 May 2005 Posts: 8

Maybe this is something that could be looked into by examining the contents of the 1.0 Firmware dump... I would but I have no idea about any of this PSP stuff... but I figured... if its doing it at cold-start then it must be in the firmware

sorry if I'm pointing out the obvious :S

Pikoro · Joined: 13 Jan 2005 Posts: 56

Another thing i was thinking about is... perhaps it's looking for a theme to be loaded?

I've been playing around with tossing different types of files in different directories on the memory stick.. but haven't really put much time into it since i've been busy with other stuff...

Cheers

konfig · Joined: 06 Jan 2005 Posts: 68

If the psp is finding bootable data, the bootable data in the ms may not be files. It may be stored in some boot section, or even in some unknown area.

I know about the ms hardware, so it is only a guess.

konfig · Joined: 06 Jan 2005 Posts: 68

Fabre · Joined: 22 May 2005 Posts: 18

I noticed that in the technical specs, it mentions 4 MB of DRAM. Is the other 32 MB Static RAM? If it is, you could just hook up an external power source to the RAM chip, wait until a point at which the decoded modules would be in RAM, then disconnect the chip, keeping the power lines attached. Drop it in a reader, and you have all the decoded modules you need :D

darkfader · Joined: 27 Mar 2005 Posts: 8 Location: Netherlands

Hmz.. that's not very easy to do :)
What about loading some tiny program into memory (some OS call) before starting a real game and then trap the call and dump the memory?

Guest · Posted: Fri Jun 10, 2005 9:38 pm Post subject:

tazaleth · Joined: 29 May 2005 Posts: 6

I believe a tool recently came out that does in fact run in kernel mode and allow one to dump memory. KDumper. It has source included. It should be available here on ps2dev, seeing as they are the ones who released it.