Restore/recover Supersonic Matrix SC-91JB Android tablet

Question

My friend brought me his granddaughter's tablet a couple weeks ago and it was stuck at the Android logo screen, just gray "android" text with white highlight moving across repeatedly.

I already had ADB from some stuff I was doing on another Android tablet some time ago. I was able to connect to the tablet using ADB. I searched around and found the adb shell wipe data command and that got the table working again. Gave tablet back to little girl and everyone happy.

He just brought me the tablet again, same problem, I tried the same solution. This time it did not work. After wiping data, the tablet still gets stuck at the Android logo.

This time I found echo -e 'boot-recovery\0' > /dev/block/nandf; sync, issued the command from within adb shell, rebooted, and got an Android on his back with a green triangle / exclamation point. I hit the Home button and got into the recovery menu, but the only thing I could do was to reboot. What makes this extra tricky is that this tablet has no volume button(s), only Power and Home.

After rebooting, I got the Android logo again. I can still get into adb, so there are signs of life, I just don't know how to proceed. Manufacturer support seems to be non-existent. Don't know how to find a proper factory image to restore the tablet. Don't want to just start hacking and brick it forever.

I don't really know anything about Android but I am a pretty good (i.e. old, haha) computer guy and have general familiarity with operating systems, UNIX/Linux/Posix commands, and hardware. I should be able to follow instructions if anybody out there can walk me through this.

Any suggestion is really appreciated.

P.S. Following is output from the wipe data. I do not recall if I received similar error messages a couple weeks ago when the wipe data fixed the tablet. I don't think the tablet has ever been rooted, etc.:

D:\Users\me\Downloads\Root_with_Restore_by_Bin4ry_v31\stuff>adb shell wipe data
Wiping /data
rmdir() error on '/data/system/dropbox' 'Read-only file system'
rmdir() error on '/data/system/throttle' 'Read-only file system'
rmdir() error on '/data/system/shared_prefs' 'Read-only file system'
rmdir() error on '/data/system' 'Read-only file system'
unlink() error on '/data/backup/pending/journal-133428497.tmp' 'Read-only file system'
rmdir() error on '/data/backup/pending' 'Read-only file system'
unlink() error on '/data/backup/com.android.internal.backup.LocalTransport/@pm@' 'Read-only file system'
unlink() error on '/data/backup/com.android.internal.backup.LocalTransport/@[email protected]' 'Read-only file system'
rmdir() error on '/data/backup/com.android.internal.backup.LocalTransport' 'Read-only file system'
rmdir() error on '/data/backup/com.google.android.backup.BackupTransportService' 'Read-only file system'
unlink() error on '/data/backup/ancestral' 'Read-only file system'
rmdir() error on '/data/backup' 'Read-only file system'
unlink() error on '/data/system.notfirstrun' 'Read-only file system'
unlink() error on '/data/anr/traces.txt' 'Read-only file system'
rmdir() error on '/data/anr' 'Read-only file system'
unlink() error on '/data/cfs.version' 'Read-only file system'
unlink() error on '/data/tombstones/tombstone_00' 'Read-only file system'
unlink() error on '/data/tombstones/tombstone_01' 'Read-only file system'
unlink() error on '/data/tombstones/tombstone_02' 'Read-only file system'
unlink() error on '/data/tombstones/tombstone_03' 'Read-only file system'
unlink() error on '/data/tombstones/tombstone_04' 'Read-only file system'
unlink() error on '/data/tombstones/tombstone_05' 'Read-only file system'
unlink() error on '/data/tombstones/tombstone_06' 'Read-only file system'
unlink() error on '/data/tombstones/tombstone_07' 'Read-only file system'
unlink() error on '/data/tombstones/tombstone_08' 'Read-only file system'
unlink() error on '/data/tombstones/tombstone_09' 'Read-only file system'
rmdir() error on '/data/tombstones' 'Read-only file system'
Done wiping /data

Answer 1

Playing around with "mount" and various commands, it looked like the /data file system was already mounted r/w. This left me with the option of trying to reload a "factory image".

The link you posted was informative and looks like a good resource, however I am a bit gun-shy about trying to load code that was not specific to the exact device in front of me, as I got burned on that once before (fortunately that one was resolved when the manufacturer finally made the correct stuff available).

I was finally able to get this one working without having to resort to trying a generic A10 image. I ended up using "echo -e 'boot-recovery\0' > /dev/block/nandf; sync", from within adb shell, connected a standard USB Windows keyboard from a PC, then issued "reboot" command still from within adb shell. Again I got an android on his back with a green triangle / exclamation point. I hit the Home button on the tablet and got into the recovery menu, and voila, the arrow keys on the keyboard actually worked to navigate the menu. I selected the option for wipe data / factory reset and used the Power button on the tablet as Enter, used the keyboard again to navigate the "are you sure" prompt, Power button again for Enter. The device showed that it was formatting /data and some other file system (I forget), then when it was done it went back to the recovery menu. I disconnected the USB keyboard and hit Power one more time to reboot, and this time we made it past the Android logo and back to a like-new out-of-box state! Back in business!

The concept of connecting a PC keyboard might be a breakthrough for anyone struggling with recovery on one of these tablets with no volume buttons, though I can't say it was entirely my idea. It briefly flashed through my mind at one point but I didn't actually try it until another post I read somewhere kicked me again. ;-)

p.s. I don't know if the exact sequence of connecting the keyboard etc was significant, but I figured I'd try to be specific just for the benefit of anyone reading this in the future.

Answer 2

OK, got an update. I posted a long thread here a while back and it got deleted. I've got better news this time.

1. SC-91JB is the same as the Turkish Piranha Business II TAB 9.0. Go to this site (its in Turkish) and download Livesuit and Phoenixsuit from the "Destek" -> "Sürücü ve Yazılımlar" tab.
2. You can get the firmware there, (it's the plain 4.1 JB ROM) but there's a better place.
3. Install Phoenixsuit and Livesuit. Make sure you install the drivers.
4. Connect your tablet and open Phoenixsuit (if updates are available, then update.)
5. Go to the "Firmware" tab and choose the P422 ROM you downloaded earlier, then hit upgrade.

There's a high chance the upgrade will fail to go through on the first try. When it did on mine, it gave me instructions saying you had to hold the power button down for 10 seconds, then a series of button presses and connecting the tablet to the pc. Make sure you use a good USB cable. When I followed the on screen steps, Livesuit popped up and I was able to force a firmware upgrade. The screen on the tablet stays dark, but the "Firmware" screen on Phoenixsuit will show you the progress.

Once that's finished, My tablet started up with the "Piranha" logo and booted into Android. Of course, Android was in Turkish so I just went into settings and changed the language to English. This ROM includes a lot more apps than the Supersonic one did (including Angry Birds Space.) I just did this update today, so now I will see if the issues we were having were due to the ROM or hardware.

Summary: This method can revive a tablet that is completely dead! So Philip, in your situation, you may simply have to plug in and force the upgrade. A long press of the power button will switch the internals on and off.

This is a super easy way to get your tablet back up and running without having to drop to the command line. Most of all, good luck!!!