[UnBrick]TOTAL WIPE and reflash back to 1.4.0 via Ubuntu Recovery --Now Easier!!!!

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This post can unbrick any Nook Tablet as long as there is no hardware damage.

Introduction
Some of you might know that I've been working on getting Ubuntu 11.10 running on the Nook Tablet. Why Ubuntu 11.10? It's optimized for touchscreen. My work with Ubuntu is not totally ready yet. The touchscreen is totally wonkey and unusable for touch input.

...Well, without a 3.0 kernel tailored to our device, Ubuntu is quite unusable as a Graphical User Interface. I've tried to compile a few times without any real results to report. The best results I've come across use a 2.6 kernel based on the kernel used for our device by Android. Anyway, if anyone can help get us a operational 3.0, 3.2+ kernel with full support for our device, I can get Ubuntu running.

However, all is not lost. Ubuntu DOES boot on a 2.6 kernel and it WILL perform most tasks that do not require special device control, like wiping the disk and reflashing. I've come up with a total wipe and restore program for SDCard based on ubuntu.

So, as a result of my work, I would like to present the first ever Ubuntu Recovery. This will totally wipe your device. With the exception of the ROM Partition which contains serial information, every single partition will have zeros written to it then flashed with just enough to perform an initial factory reflash. Normally when you perform an update or flash of a device, it is simply formatted. A formatted device can be unformatted. A zeroed device cannot be unformatted. All information is overwritten with zeros.

This will also work if you've damaged the bootloaders or recovery partition.


how to create your own bootable Ubuntu Recovery SDCard


You will need:

• A Class 4 SDCard with at least 4Gigs of space
• 6 gigs of free space (for downloading sdcard image and uncompressing)
• The SDCard Image: http://ge.tt/9rVFXxC?c

Linux/Mac Instructions

1. Open a terminal in Ubuntu by typing "terminal" in the search bar then hit enter
2. uncompress the Downloaded SDCard Image
   

   cd ~/Downloads
   tar -xvwzf ./AdamOutlerUbuntuTotalReFlash.tar.gz

3. With the SDCard or reader removed from the computer, get a list of all disks

   ls /dev/sd?

4. Insert your sdcard or usb sdcard reader, then press the up key and enter to repeat the last command. The new device will show up as sdb, sdc, sdd or sde. each new device gets a higher letter. Note this newly plugged in device.(ie. /dev/sdc)
5. Use the following command to make your new SDCard, where "sdc" is the name of your SDCard device.
   

   sudo dd if=./AdamOutlerUbuntuTotalReFlash of=/dev/sdc bs=4096; sync

   Wait 5-20 minutes (depending on SDCard speed) until the image burning completes.
6. Shove it in your nook and turn it on by inserting the USB cable(do touch the power button, just insert the usb cable). Your nook will boot Ubuntu and perform a total factory restore. The process will take 15 minutes to complete with a Class4 micro SDcard.

Pro-tip: to copy and paste easily in Ubuntu, highlight text in the browser, then press the middle mouse button on the terminal.
Pro-tip: The tab key will auto-complete filenames.


Windows Instructions
Thanks to cyberma007 for Windows instructions.

• Extract AdamOutlerUbuntuRecoveryImage with Winrar
• Rename the resulting file to Add the .img extension to the filename
• Download and open Win32 Disk Imager. note: The open source project can be found here: https://launchpad.net/win32-image-writer
• Choose the drive letter of your SD Card from Win32 Disk Imager
• Click the Write button
• Turn of your nook and put in the SD Card and turn it back on.

Your Microsoft®™ Windows©®℠ computer sucks at reading anything except Microsoft formats. It cannot read the Open Source Linux EXT4 format. You will only see one partition after creating the SDCard but it will work fine. If you want to inspect the contents, install a Linux distribution on your computer.



Theory of operation
how it works
When you insert the SDCard and turn on the device this is what happens.

• The device boots from SDCard.
• The Ubuntu GUI will load. Personally, I recommend that you do not touch anything
• You will be presented with a 100 Second countdown
• If you wish to stop, press and hold power for 10 seconds before flashing has started
• You will be presented with a progress bar status update only. Closing this will not affect the process. the only way to stop is to turn the device off.
• At this point, the flashing process will begin

Flashing Process
After Ubuntu has booted here is the procedure which takes place

1. MLO partition will be written with all zeros, then flashed
2. U-BOOT partition will be written with all zeros, then flashed
3. RECOVERY partition will be written with all zeros, then flashed
4. BOOT partition will be written with all zeros, then flashed
5. BOOTDATA partition will be written with all zeros, then flashed
6. BOOTDATA is mounted and a command is sent to factory reset the device upon next boot.
7. FACTORY partition will be written with all zeros, then flashed in two parts to work around a 120 second filesystem operation bug.
8. A sync operation takes place to ensure all data is written to the device
9. SYSTEM partition is wiped with all zeros
10. SYSTEM partition is recreated as a blank EXT4 filesystem
11. CACHE partition is wiped with all zeros
12. CACHE partition is recreated as a blank EXT4 filesystem
13. SDCARD partition is wiped with all zeros
14. SDCARD partition is recreated as a blank FAT32 filesystem
15. A sync operation takes place to ensure that all data is written
16. You are notified to press and hold power. When the screen goes black remove your SDCard

note: Using a Class4 SDCard, the screen timeout will be aproximately 30 seconds after the entire operation has completed. Do not confuse screen-timeout (blank screen) with turning off the device (black, unilluminated screen). Turn the device off and then remove the sdcard or risk corrupting the data on the sdcard.

It's my intention that this may help someone. This will at least be one more method for people to try before giving up on restoration to 1.4.0. I generally receive 5-10 PMs per week requesting support on the acclaim_update.zip. Hopefully this will reduce those and give people another option to try.

Ubuntu isn't ready for daily use yet, but this recovery tool is more thorough than any other recovery method out there. I need some help porting the 3.0 kernel to the Nook Tablet.

Note: to neuter recovery and just use ubuntu, remove the file called /root/recovery from the sdcard before loading into your Nook.

Which kernel branch did you try to build?

Originally Posted by Kuzma30

Which kernel branch did you try to build?

I've tried several. The problem is in configuration. I eventually settled for the stock 2.6 android_4430BN_defconfig. It seems to function best for this until we have a proper 3.0 kernel.

Thanks Adam very nice work. Question what if we want to revert to 1.4.0 or 1.4.0 is it possible or we will be stick it lol. Can this be supported for dual/multi boot?

~ Veronica

Sent from XDA premium using my Nook Tablet :P

Very good work Adam.
I have one trivial question... Why on all your projects do you use Ubuntu and not any other distro?

Originally Posted by lavero.burgos

Thanks Adam very nice work. Question what if we want to revert to 1.4.0 or 1.4.0 is it possible or we will be stick it lol. Can this be supported for dual/multi boot?

~ Veronica

Sent from XDA premium using my Nook Tablet :P

Thats what this does. It reverts you to 1.4.0. It uses Ubuntu as a dedicated recovery. If you would like to dual boot, just remove the /root/recovery file. You can boot Ubuntu or normal by inserting and removing the sdcard. But like i said, the touchscreen is wonkey and there's no way to fix most of the problems without a 3.0 kernel.

Originally Posted by ShadowReaperGR

Very good work Adam.
I have one trivial question... Why on all your projects do you use Ubuntu and not any other distro?

I use Ubuntu on my desktop. I like Ubuntu because it has a large user base and if i come across a problem, it is easier to correct or has generally at least been discussed. For a mobile device, it makes more sense than other Linux distributions because newer versions have been optimized for touchscreens. In general, i find Ubuntu supports more things than other Linux distributions.

Hoster: http://ge.tt/ or 4shared.com both max. upload 2Gb/file.

Originally Posted by AdamOutler

Thats what this does. It reverts you to 1.4.0. It uses Ubuntu as a dedicated recovery. If you would like to dual boot, just remove the /root/recovery file. You can boot Ubuntu or normal by inserting and removing the sdcard. But like i said, the touchscreen is wonkey and there's no way to fix most of the problems without a 3.0 kernel.

Gotcha! thanks Adams, i'll wait until it gets a better kernel, i love the Ubuntu idea .

My 2 cents for host: http://minus.com/

Great work, will monitor this. Would be nice to have Ubuntu fully working on the Nook Tablet (or Nook Color, for that matter -- seems like development on that has died, shame as they are now $129 refurbished direct from B&N)