Viewing File Directory from NAND Flash Chip

[fzabkar]

BTW, when 7Zip identifies an archive as LZMA:nn, it means that it was compressed using the LZMA algorithm with a dictionary size of 2^nn bytes.

[Crawlie69]

Thank you! I'm very busy for the next couple of days, but i will certainly have some fun trying out the solutions you've posted soon. Hopefully i can get it working, either with the vw logo from the other eeprom dump, or with my own!

Thanks!

[Crawlie69]

Just a quick update - I've tested my first flash, where i changed some of the stock screen settings/values along with Carplay being the selected setting from default in one of the menus. Worked perfectly!

However playing around with this bootlogo boggles me.

You can paste this logo into your MINFS volume at offset 0x743040. That is the beginning of the free space.

However when i look at the offset you stated above, it appears to me, that it is in the middle of the MINFS volume. Am i wrong?

https://imgur.com/DHWoaGu

[fzabkar]

Since my program operates on the MINFS volume, not the whole EEPROM image, the offsets are relative to the start of the MINFS volume.

[fzabkar]

Try this (your VW logo):

http://www.users.on.net/~fzabkar/temp/Headuniteeprom_logo00_VW_LZMA_64KB.7z

If that doesn't work, I'll rebuild it with the other VW logo.

[Crawlie69]

Thank you! I'll give it a go tomorrow - Fingers crossed

[fzabkar]

Here is another hack, this time using the VW logo in the OP's EEPROM:

http://www.users.on.net/~fzabkar/temp/Headuniteeprom_logo00_VW_LZMA_64KB_working.7z

If neither works, then there may be a checksum that needs to be recalculated.

[Crawlie69]

SUCCES!!!

https://postimg.cc/7fWBSL9n - Sorry for the dirty car lol!

I can not believe this actually worked out in the end!
Thank you for all your help fzabkar! Without you this would never have happend. This whole project was much bigger than i ever imagined.

If you want some compensation for the time you've wasted on this project, i'll happily send you some funds

And while i probably asked you too many questions.. I was wondering...
The headunit resets sometimes, and while it luckily doesn't reset the boot image, it resets the settings. I've developed some preferred screen settings, and then i have to change those whenever it resets. While i've been able to change this in the firmware, and make it work, it still resets to the stock settings whenever the headunit resets. Luckily enough it doesnt reset the boot image though.

Do you reckon this is checksum related, something else or?... Maybe this is another rabbithole we shouldn't jump in lol.
Thanks for all the help!!

[Crawlie69]

I found the stock values under MINFS_01\$Root\app_config.fex - I guess this file is used for the 'temporary' storage, and then the actual stock values must be hidden somewhere else. Doesn't make sense how the values change back to the stock values otherwise..

[fzabkar]

There doesn't appear to be a checksum, else the head unit would not have booted.

This project was useful for me because it motivated me to write a tool to traverse a file system. I think I should be able to use similar code for traversing the proprietary file systems in some DVRs.

[Crawlie69]

There doesn't appear to be a checksum, else the head unit would not have booted.

Guess you're right. I'll do some investigation when i feel like it. I am just so relieved that the boot logo is replaced. Absolutely brilliant work you did. Crazy to me that a stranger on the other side of the planet made this possible.

This project was useful for me because it motivated me to write a tool to traverse a file system. I think I should be able to use similar code for traversing the proprietary file systems in some DVRs.

I'm happy you atleast got something out of it then. Certainly been a learing experience for me as well. I can not thank you enough!