XD card recovery experiences

[shaun]

Hi all,

I'd like to discuss your experiences in XD flash data recovery. We got an original Olympus 1gig card which is not recognized by a common flash reader anymore. The card consists of a thin PCB with the controller as a COB and a standard 56pin TSSOP packaged flash. I wonder whether the controller performs only conversion tasks or also does wear levelling and maybe also security tasks. I must admit that I've not started any research yet when it comes to Smart Media or XD, which I will do this evening. In order to make use of the plain dump of the flash chip, I'd need to know what kind of treatment is performed in XD cards. Maybe I'll have a look whether I can find JPEG headers in the chip or its inverted image and if yes buy an identical card and swap the chip. Probably also the flash chip must be the same for this purpose, maybe it is irrelevant when I only need read access.

[dobrevjetser]

Shaun,

The data is mixed on those cards; finding a jpeg file there is impossible.
The processor indeed takes care of wear-levelling etc...
This can only be solved with special software like from ace or soft-center.

Best regards,

Dobre

[dick]

Hi,

If you can get the 56 pin tsop off of the old card you would of course dump the contents as a backup. Then if you can find an identical working card, with good soldering skills and tools, it should be possible to swap the tsop device to the new replacement. You should then be able to access the data in the standard manner.
Thats how I would approach it.

[hddguy]

Hi,

If you can get the 56 pin tsop off of the old card you would of course dump the contents as a backup. Then if you can find an identical working card, with good soldering skills and tools, it should be possible to swap the tsop device to the new replacement. You should then be able to access the data in the standard manner.
Thats how I would approach it.

You have a lot of success with this method?

[pepe]

since usually it is not the controller that is faulty, this chip-swap method is unlikely to work.
usually the controller messes up some of his own information stored inside the flash memory itself, that's why it (and any other controller) cannot access the data anymore.
U need to read it out and reassemble the LBA space in some way.

regards,
pepe

[mediaman]

do you mean the more common problem is that one of the memory chips behind the controller dies? I guess the solution to problem is similar to one bad head as you say: dump available LBA's and see what you can get? With high megabyte picture size and the JPG file format it does not sound like you would get many back.

What "strip size" is used across the memories? the common ones at least? I have not had a case yet but would like to prepare.

[dobrevjetser]

Never had a memorychip that "died" till now.
The "striping" as you say is a very complex pattern and different for each manufacturer and even between devices from the same manufacturer.

Creating the software to reconstruct the data yourself is a very very tough job.

Dobre

[pepe]

Hi,

I didn't mean that the memory IC is damaged. I meant that the data became corrupted. If U want do use the harddrive analogy, it is similar to a FW corruption.
I suggest U to download a datasheet of such a flash memory IC and get some faint idea how these devices work and how to access them. Reorganizing the blocks can be easy as well as really tough depending on the controller and the number of memories connected to it.

pepe

[dick]

Hi,

If you can get the 56 pin tsop off of the old card you would of course dump the contents as a backup. Then if you can find an identical working card, with good soldering skills and tools, it should be possible to swap the tsop device to the new replacement. You should then be able to access the data in the standard manner.
Thats how I would approach it.

You have a lot of success with this method?

Yep. I have used this method about ten times and have a 100% success rate.
The hardest part is often to find a suitable recipitent device!

As for corrupted data in the flash memory chip I have yet to encounter a single case but I realise it is always a possiblity. If the data is corrupted then the job would be very hard indeed as the block order, striping etc would be even harder to work out. In that scenario I don't think it would make economic sense for most cases.
Maybe I was lucky on all those 10 or so recoveries.
My view is to try the easy/inexpensive method first and then move to the next.

[pcimage]

I can probably do this for you (I'm in UK)

Or dobrevjetser can do it to, in Belgium.

Or Mr_Spokk in Sweden.

We all have the soft-center kit, and know how to use it!

Sean

[shaun]

Hi all,
thanks for all those replies.
I have the soft-center reader and the module for sm32x controllers (so far) as well, have practiced with two of my own USB sticks (a 128MB and a 1GB one) with good success, but am still failing with a 4GB stick. Maybe one of you have seen my threads in the soft-center forum. The 4 gig one is quite disgusting, at the moment it seems that I have the right block size, mix parameters and so on. Maybe I'll send the whole dump to Sergey and his colleagues, this usb pen really sucks.

But back to topic, the XD card seems to be physically damaged. Several solder connections of the TSSOP are broken, and I've not yet backed it up, so resoldering it and firing it up to give it a try was not an option so far. If this already succeeds, fine. If not, I'd prefer to transplant the flash to an identical PCB, so I must assume that the controller does not store any adaptives internally. As long as I've got a backup, the loss would be minimal - like ten bucks for the card in the worst case.

[pcimage]

Sorry, I didn't realise you had Sergey's kit!

You username here must be different to your Soft-Center one, what's your username on there?

Cheers

Sean