PSP Flash Chip Facts: The Good, the bad and the ugly

[wraggster]

McZonk has posted this great article :

http://psp-news.dcemu.co.uk/files/flash-small.jpg

With the help of some university lecturer I have removed the flash chip from a psp board. Neither the board nor the chip are damaged. My idea is to build a PSP with 2 flash roms. If I brick one, I can restore it with other one. Everybody how has a bricked PSP can help Team Emergency Exit with giving us the board. I also need some money for build a circuit board to attach two on. Contact: [email protected]

The Good Facts

The chip is a standard chip from Samsung: K5E5658HCM (http://211.45.27.232/Products/Semiconductor/Support/ebrochure/hddodd/Memory_Storage_Product_Selection_Guide_050602.pdf) . There is nothing secret with the chip. Everybody can buy it, if you take 1000 :D

The Bad Facts

The chip is not only the flash rom (256 mbit nand rom). It is also the ram (256 mbit ddr ram). If you read though the datasheets of the chip, you will find there figures. The flash is built from nand gates. It won't be as easy as access nor gates. So direcly writing into the flash is not easy.

The Ugly Facts

If you look at the board, you will see the wire loops from processor to the flash/ram chip. These wires are made to keep all wires in the same length. This is important for the timing of the ram and timing is very very cirical. If I brought back the flash/ram on the board with just some small wire brigdes, it could disturb the timing of the ram. The flash is not critical, but the ram is.

I will also try to build a two flash psp.

It seems that the article that was posted here exclusively by McZonk has yet again been stolen and worse the site who stole it is getting credited, our apologies to McZonk about these sites :(

[jwilds73]

So what is the idea here to add a second chip to the psp and keep one at say 1.5 OS and then the second whatever the newest version is and just have someway to toggle between which chip (OS) you boot?

[jimjamjahaa]

possibly, tho i think maybe it is so you can f**k with the firmware as much as you like and not end up with a brick (backup flash chip)

so you could make your own firmware based on sony's or linux or whatever

[LampDev]

Yeah, if he expects money and psps to test, he should really explain his full purpose.

What does he want these to do? To start an unbricking service for PSPs? To flash PSPs back to 1.0 or 1.5 the hard way?

[eretsua]

would be interesting to see where this could lead. though, i agree that a more elaborate explanation is necessary.

[Hidavi]

256MB RAM? Then why do all the spec lists say 32MB RAM? I think that Sony might've ordered a special version of the K5E5658HCM chip with only 32MB because no way the PSP has 256MB.

[danhans115]

The PSP does have 256Mbits(Megabits) of RAM which equals 32mb (megabytes). Something to do with there being 8 bits in a byte or something..

[alexh]

This seems a bit of a waste of time. As said DDR timing is VERY sensitive, moving the chip onto a second board probably wont work.

I would imagine though there is a test header / JTAG port to allow the Flash to be programmed as the PCB is being assembled (without using the PSP's CPU) that would be the place to look for.

[LampDev]

From the guy's site (http://www.teamemergencyexit.com/projects.html):

The concept is to build a PSP with two flash chips on. This will be very helpful vor developer because if one firmware is damaged it can be reseted.
I wouldn't give anyone anything who screws up the english language that much in two short sentences. On top of that, there's STILL no information as to what they plan to do once they do get one working. I'm guessing they plan on selling the modded PSPs.

[PSP_Newbie]

I would assume the grammatical and spelling errors might be due to living in another country in which english is not the primary language
just wanted to bring this up as almost every time i see bad spelling in a release comment like this it is due to them not being a native english speaker, and someone always brings up their ability to speak english with the unrelated software/hardware-related comment, but then i could be wrong :D

[McZonk]

I wouldn't give anyone anything who screws up the english language that much in two short sentences. On top of that, there's STILL no information as to what they plan to do once they do get one working. I'm guessing they plan on selling the modded PSPs.
Calm down Cowboy. Sorry for my English, it is not my native language. But I will correct it.
There will be and update soon. With some more information how to reflash the second chip.
The Dualflash PSP may be interessting for consumer, but it's focus is for psp developers. Because remove and bring back the flash on the platine is a high risk.

[LampDev]

Because remove and bring back the flash on the platine is a high risk.
OK, I won't fault you b/c english is your second language, but you still need to provide a bit more details about what you are doing and what you plan to do once you do it.
Again, you can't expect money and PSPs to be thrown at you just because you put up a picture of a PSP board and state some vague promise about a dual rom PSP.

We understand that the concept is nice for a dev, but do you plan on selling them or what in the future? Do you want developers to send a PSP for you to mod and then have shipped back to them? What is your purpose?

[McZonk]

A lot of people ask about some more details about the dualflash concept. Here are some. Please remeber that all this is just a theory, but I'm convinced that it will work.
The basic plan was an unbrickable psp for support the developers who like to play around with firmware, exspecially Placa from Team Emergency Exit. There are a lot of concepts you can find in the net out there. My idea is a little circuit board with two flash chips mounted on and the possiblitly to switch between the chips. If one firmware is damaged you will be able restore it with the other one. Here is the point where a lot of people ask: How to do that? The answer is simple. Use the second flash to start an update to 1.5 and just before the update starts switch between the flashes. It should also work if the seconds flash has firmware 2.01 or higher or even if the second flash is empty. The switch will only made for the nand-flash, not the ram. This is possible because both compontents have their own power supply.
Some other facts. No it won't be a universal downgrader. To create a dualflash psp is a very high risk. It's not made for consumers. I don't plan to start a service for building dualflash psps or reflash bricked. What price I should take for this mod? It must be much more expensive than a normal psp, because the risk to destroy the board is so high. Perhaps some other one will take this risk. I will distribute the circuit board or the plans for it, if some others want try to build their own dualflash psp. But this will only happens if I got my first successful modded psp.
The prototype will be in an uncovered psp. But the circuit board will be small enough to build in a psp. This is important because the ram timing is so critical and as shorter as the wires will be so smaller the problems are. I good thing is that the bus frequency is only 111 MHz normal. But perhaps it won't be possible to clock the psp back to 166 MHz bus freq.

Copy from my dev blog teamemergencyexit.blogspot.com

If you still gut question, feel free to ask me.

[bobcobb]

They are german, and they fixed the grammatical errors. It seems to me like this is legit, although I don't know what great overall task it would accomplish.

[LampDev]

They are german, and they fixed the grammatical errors.
May Buddha smile upon them for that small kindness. :)

From what I can make out from the site and his posts, it seems as though he wants to make a personal board for his own private team of tinkerers then release a 'Proof of Concept' instruction set for others to do on their own.

So again, everyone has to ask, what's in this for me if they are only ones who will be benefitting from this endeavor. I don't think most programmers will be taking apart their PSPs to follow a set of instructions that, by their own account, would be 'high risk'.

So what else could come of this? 3rd party 'Mod Chip' manufacturers who get the plans then turn out a few hundred modded PSPs for direct sale to developers? I somehow don't see that happening. Mostly because I think Sony would send out their team of super lawyers before they took their first order.

I don't see the point of this project other than satisfying a 'what if' concept. Now, IF they had said straight away that they were going to start a service to help other developers by taking in PSPs and modding them themselves for a fee, then I can see that as helping out the rest of the development community. Then again, there's Sony again with the super lawyers.