How To Dump The Stock ROM from an Amlogic Based Nextbook Tablet

[WimK]

It's mostly safe... you can do some damage with the terminal app and dd command if you're overly careless... but you'd have to stray really far from the instructions here to damage anything...

The scripts are installed via an option in the app from the play store. That part is simple. Just download the apps from the play store (links are in the first post) and follow the instructions in the first post.

It does require root.

The only part that might differ will be the partition layout and file paths.

ShaunMT

Great, thanks a lot!

[SweetAction]

"Now you can do a simple backup with the default settings."

Do i need to do both?


The only way to get all of the other partitions is to dd them in a terminal app. (You can't just DD system too because it is ubifs.)

I like this terminal app:
https://play.google.com/store/apps/details?id=jackpal.androidterm


Here is how to use dd to dump partitions:

Open your terminal app.

Type the following:

          
cat proc/mtd

You should get output something like this:

          
dev:     size     erasesize     name 
mtd0: 00800000 00200000 "bootloader" 
mtd1: 00800000 00200000 "logo" 
mtd2: 00800000 00200000 "aml_logo" 
mtd3: 00800000 00200000 "recovery" 
mtd4: 00800000 00200000 "boot" 
mtd5: 20000000 00200000 "system" 
mtd6: 00800000 00200000 "cache" 
mtd7: 40000000 00200000 "userdata" 
mtd8: 18c00000 00200000 "NFTL_Part"

You need bootloader, logo, aml_logo, recovery, boot, and system for a full ROM.

Cache is user settings. Userdata is downloaded apps. System, cache and userdata can't be backed up properly using dd. (Use Online Nandroid Backup from the play store.)

Don't mess with NFTL_Part!

Output file names should be as follows:

"bootloader" = bootloader.img
"logo" = logo.img
"aml_logo" = aml_logo.img
"recovery" = recovery.img
"boot" = boot.img

So your command lines for dumping should be in this format:

dd if=/dev/mtd/mtd# of=/sdcard/external_sdcard/ouputfilename

Check your mtd#'s on your device using cat proc/mtd and fill in the mtd#'s and output file #'s and enter the dd commands one line at a time.

You'll need root access to do this, so first type:

su

If your cat proc/mtd output matches my device, then your lines would be:

dd if=/dev/mtd/mtd0 of=/sdcard/external_sdcard/bootloader.img 
dd if=/dev/mtd/mtd1 of=/sdcard/external_sdcard/logo.img 
dd if=/dev/mtd/mtd2 of=/sdcard/external_sdcard/aml_logo.img 
dd if=/dev/mtd/mtd3 of=/sdcard/external_sdcard/recovery.img 
dd if=/dev/mtd/mtd4 of=/sdcard/external_sdcard/boot.img

When finished, you need to type "exit" twice to exit your shell terminal.

When done, copy the files and folders you dumped off your external sd card, zip them all up together in a single zip file, upload them and let me know where I can download them.

ShaunMT[/QUOTE]

[shaunmt]

Do i need to do both?

Yes... to get a complete set of firmware files, in the proper format, you'll need to follow all of the instructions...

The first app will put the /system partition in the proper format, but won't get all of the other partitions.

The other part can get the remaining pieces, but can't get the /system partition correctly.

ShaunMT

[SweetAction]

ok 1st step done should i remove that from ext sd card to pc before step 2?

[shaunmt]

ok 1st step done should i remove that from ext sd card to pc before step 2?

I don't think it really matters... but it couldn't hurt...

[SweetAction]

i have the same mtd# order

so i would type this in after

app_64@android:/ $

/dev/mtd/mtd0/sdcard/external_sdcard/bootloader.img /dev/mtd/mtd1/sdcard/external_sdcard/logo.img /dev/mtd/mtd2/sdcard/external_sdcard/aml_logo.img /dev/mtd/mtd3/sdcard/external_sdcard/recovery.img /dev/mtd/mtd4/sdcard/external_sdcard/boot.img

our size and erasesize are diffrent but same mtd name an order

[shaunmt]

i have the same mtd# order

so i would type this in after

app_64@android:/ $

/dev/mtd/mtd0/sdcard/external_sdcard/bootloader.img /dev/mtd/mtd1/sdcard/external_sdcard/logo.img /dev/mtd/mtd2/sdcard/external_sdcard/aml_logo.img /dev/mtd/mtd3/sdcard/external_sdcard/recovery.img /dev/mtd/mtd4/sdcard/external_sdcard/boot.img

our size and erasesize are diffrent but same mtd name an order

one line at a time... don't forgot the dd command at the beginning of each line

Each line may take awhile to finish, depending on the size of the partition...

ShaunMT

[SweetAction]

so type exaclty this for the first line


dd if=/dev/mtd/mtd0 of=/sdcard/external_sdcard/bootloader.img

then conuite after its done with its thing correct sorry for being a complete face to palm on this

[shaunmt]

so type exaclty this for the first line


dd if=/dev/mtd/mtd0 of=/sdcard/external_sdcard/bootloader.img

then conuite after its done with its thing correct sorry for being a complete face to palm on this

yes... you've got it correct now...

ShaunMT

[SweetAction]

cannot open for read: Permission denied , do i need a pro version to do this step?

[SweetAction]

Forgot the su cmd disregard thanks

[shaunmt]

cannot open for read: Permission denied , do i need a pro version to do this step?

No you to use the su or sudo command in the terminal to gain root...

either su to enter a root shell session then do all of the commands, or put sudo in front of each one to temporarily assign root to just that command...

ShaunMT

[Clyde]

Hi,

so I've reverted my NX008HD8G to stock to get some proper
backups done before tinkering with it any further, and
then followed the steps at the top of this thread to
dump the firmware. And now I got newbie questions.

Is it normal that boot.img, aml_logo.img, logo.img and
recovery.img are all sized 8192kb?

I've zipped up the backup files and the build.prop of
the tab, should anyone be interested. According to
ro.product.board the tab identifies itself as EBM8000ND_211,
the sticker on the back lists it as NX008HD8G with
serial YF0114*****, produced january 2014, bought
august 2014.

http://www.mediafire.com/download/osuazya4ck8u2se/NX008HD8G_stock_rom.zip

Best regards,
-Clyde

[shaunmt]

Hi,

so I've reverted my NX008HD8G to stock to get some proper
backups done before tinkering with it any further, and
then followed the steps at the top of this thread to
dump the firmware. And now I got newbie questions.

Is it normal that boot.img, aml_logo.img, logo.img and
recovery.img are all sized 8192kb?

Yes, that is normal, because this backup method copies the entire parition, including blank space.

I've zipped up the backup files and the build.prop of
the tab, should anyone be interested. According to
ro.product.board the tab identifies itself as EBM8000ND_211,
the sticker on the back lists it as NX008HD8G with
serial YF0114*****, produced january 2014, bought
august 2014.

http://www.mediafire.com/download/osuazya4ck8u2se/NX008HD8G_stock_rom.zip

Best regards,
-Clyde

Thanks! I didn't know they were still producing these in 2104, nor have I seen ro.product.board = EBM8000ND_211 before.

I'll download the files when I get a chance and take a look to determine what is different...

ShaunMT

[Clyde]

Heh,

just figures that I end up with some exotic model revision no one
else has seen in the wild yet. Makes customizing the rom a whole
lot more exciting, since simply flashing one of the NXM8000ND_WM
roms prolly ain't an option.

At least TWRP is working flawlessly with the tab, I've by now
restored several backups made with it, without problems.

And no Kitkat 4.4.2 in sight for the tab yet on nextbookusa.com
sadly, so I'm stuck with 4.1.1 for now. At least CydiaImpactor
can successfully root it.

Now I'll only have to figure out how to safely replace the two
horrible boot logos. ^^

Best regards,
-Clyde