Which OEM Would You Like to Help?

Most manufacturers have moments of greatness and moments of decadence, and in the past few years … more

Root T-Mobile S6/Edge on 5.1.1 Without Tripping Knox

If you purchase phones from a carrier, you may be no stranger to the difficulties … more

IonVR Coming Soon, HTC M9 Dev Edition Gets Android 5.1 – XDA TV

The HTC M9 Developer Edition has received Android 5.1. That and … more

Android 5.1.1 Omni ROM For Motorola Xoom

Back in Feb 2011, the Motorola Xoom became the first device to be sold with Android 3.0 … more

How to enable ADB on ALLWINNER A13 9" - 4.2.2 - Windows 7 - error:device not found

6 posts
Thanks Meter: 0
By Juha.Baxton, Junior Member on 12th January 2014, 01:19 PM
Post Reply Subscribe to Thread Email Thread
27th January 2014, 09:33 PM |#11  
Junior Member
Thanks Meter: 2
I did briefly try the platform-tools (since I didn't mind the OS being trashed), they didn't add any adb_usb.ini and there isn't any real indication the file was needed/didn't exist, they could've simply put a note on the ADB utility when it didn't find any devices.

I'm not sure what ADB backup does. As far as I know the mounted partition images are differently named to various backup tutorials, so I get the feeling ADB backup just simply copies the user data and not much else. I recommend doing the backup I mentioned as well, it'll at least capture a copy of the boot partition, which if the device doesn't have that you'll probably need to revert to using live suite or some other firmware utility to restore it. Getting the firmware for that is another story, read a fair amount of posts here and other places on the net that don't sound fun.

I personally still can't get superuser to behave for using su on the terminal/term.apk (I want to remove useless "system" apps and make sure the device isn't talking back to anyone, i.e. google), but I'll keep tinkering.

My main aim for getting one of these tablets was to boot other firmware from the SD slot, but it looks as if the u-boot process is locked to internal NAND. So might have to modify it by adding "fatload mmc" to the script.

4th February 2014, 03:59 PM |#12  
Junior Member
Thanks Meter: 2
Quick Update;

Right the permissions thing turned out to be an issue with Superuser, dunno why. So replace the su binary from SuperSU ( into my SUME pack and install the Superuser.apk by;

adb root
adb shell mount -o rw,remount /system
adb push Superuser.apk /system/app

as for stripping back the Applications, I've got it down to this as bare bones

adb pull /system/app backup\system\app

to backup system applications before you do anything

I found if you do delete any applications and then android gets stuck at the logo, just adb push them back and it'll boot without reboot when you've got the chain right.

minimum applications needed for boot are;

A few odds and sods missing will make settings close, but it's trivial stuff. Personally don't like the sound of Fused Location, but it won't boot without it and I haven't seen any dodgey traffic from it (yet).

I recommend installing Droidwall with adb push /system/app, before installing games.
And modifying /etc/hosts with to certain you know whos and advertisers.

Some of my personal choice replacement applications (so far);
Total Commander over ES file explorer.
Opera Classic over the inbuilt browser (although I'm still trying to remove the default search engine).

6th February 2014, 02:12 PM |#13  
Junior Member
Thanks Meter: 2
More update;

Discovered some new things;


I think performancepolicy.apk needs to be added to the bare bones application list, afaics from looking inside the package it sets system performance stuff, so likely throttling to preserve battery power.

bin_cfg.xml in /misc which can be modified by
adb shell mount -o rw,remount /misc
then adb pull, edit and push the file back

the line in there for "backlight_brightness" 780;1020;780 can be changed to 240;1020;240 which dims the backlight substantially saving battery power. not sure if 240 is the absolute minimum, but 120 seems to be too low afaics. interestingly information on the settings is in the files named _userview.xml

build.prop in /system which can be modified by
adb shell mount -o rw,remount /system
then adb pull, edit and push the file back
and then chmod 644 /system/build.prop

the lines in there for ro.wifi.signal.level.# can all be set to 0, this theoretically cuts the wifi power usage to less than 1mW, again saving battery. if android doesn't boot fully on reboot it's because chmod hasn't been set, you should be able to adb back in and correct.

please be careful modifying either file as both seem to have safety limits imposed on certain device components (i.e. battery temprature), messing with those can make the tablet stop working.

Post Reply Subscribe to Thread
Previous Thread Next Thread
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes