Help to unscramble my NAND flash

[pepe]

without ecc it does not really matter, you don't know what is good and what is bad.

pepe

[rom1nux]

supply voltage may affect data integrity but you can't really decide what's good and what's wrong without calculating ecc.
Reading same value several times does not mean it is good.
...
without ecc it does not really matter, you don't know what is good and what is bad.

Ok pepe, so I need to apply ECC on XORed (1024 bytes) data area first ?
(I thought that I need to unXOR the data area before correcting with ECC)
(I hope ECC area are not XORed )

Heating or cooling the chip can also make a difference.

Nice tips ddrecovery, it costs nothing to try, It is hot now in France, I got 27°C (80.6°F) in my room now.
I will first take out the soldering iron to make a simple breadboard adapter to remove cra..y dupont wire and shorten connection. I can add proper decoupling capacitor to have more clean power supply. (And if found it in my drawer I will add a small peltier module )

thank you both for your help

[pepe]

since you can see the SA clearly, we can say the SA and ECC is not xored.
But can't say for sure wether ECC is applied before or after XOR, probably before.
And yes, i was about to say something about shortening the wires

pepe

[ddrecovery]

FWIR, ECC is applied before XOR on PS controllers.

[rom1nux]

Thank you ddrecovery, I will try.

[Amarbir[CDR-Labs]]

Hello,
Thats a Lot of Effort ,You Can Ship The Device To Me in India And i Will Recover It For No Money ,Once i do this i will upload dump + solution and you can download and carry on with your research .

[rom1nux]

Hello,
Thats a Lot of Effort ,You Can Ship The Device To Me in India And i Will Recover It For No Money ,Once i do this i will upload dump + solution and you can download and carry on with your research .

Many Thank Amarbir, this is a really very nice offer, I thank you a lot, let me try a few more hours and if I can't achieve the solution I will send you the device. (Nice YT channel Amarbir you have one more subscriber)

[rom1nux]

I rebuild my reader to increase reading stability. It seem to wok well.

Now I can go deep into ECC / BCH....

[lcoughey]

I rebuild my reader to increase reading stability. It seem to wok well.

readerv2.jpg

Now I can go deep into ECC / BCH....

I'm curious to know how much it cost you to build your reader (time & $$$) in comparison to the $210USD for the flash-extractor reader (http://www.flash-extractor.com/shop/).

I'd also like to know if your setup will allow you to re-read the bad blocks after ECC is run on the dump.

Either way, you certainly have a lot of drive, persistence and free time to be doing this for your friend. I sure hope that they appreciate what you are doing for them.

[pepe]

re-read is a question of sw, and it is obvious he can do it if he got this far...
The FE reader would not allow this without the SW which costs 1.5k+ as per my memories.
Hats down for this project

pepe

[ddrecovery]

The OP has put a lot of work an effort into this and has done extremely well so far. He could however have got a free evaluation from a data recovery company first. If it was found to be a PCB issue it might have been $100-$200. But if he is doing it for fun and learning, then that is cool.

[lcoughey]

re-read is a question of sw, and it is obvious he can do it if he got this far...

I assume that he will be able to do that, but figured he hasn't gotten that far yet.

The FE reader would not allow this without the SW which costs 1.5k+ as per my memories.

The reader will work fine with NAND Reader without a Flash Extractor license. It is only when you go further with ECC and piecing it together that you need to have the license for Flash Extractor.

[pepe]

yeah, the FE reader does exactly what he already achieved so far, but he could not get further with FE without the license, so he is better off with his own setup that he can develop it as he wants.

pepe

[lcoughey]

yeah, the FE reader does exactly what he already achieved so far, but he could not get further with FE without the license, so he is better off with his own setup that he can develop it as he wants.

True. Perhaps he'll be able to recoup his costs by marketing his own product.

[rom1nux]

Hello,

Yes I spend ~30 min per day, not every day. I write my own C console application to download data from the reader. Yes I can set the start block and end block on the command line to download a block series or all.

I build the reader with what I have under my hand. I did not calculate the price of hardware, but it's something like :

Code:

NUCLEO L476RG    15.00 € 
TSOP48 ADAPTER   10.00 €
FT232H BREAKOUT  10.00 €
PROTOBOARD        1.00 €
WIRE+CAPA         1.00 €
-------------------------------
TOTAL            37.00 € (43 $)

It's really interesting technology but the main purpose is to help my friend

[rom1nux]

Return to deep linear code block theorie for BCH ...