3Q Q-Pad RC0710B

[EighthPieceOfNine]

Hello!

I recently got hold of a 3Q Qoo! Q-Pad RC0710B. It's a dirt-cheap 7" Tablet running Android 4.0.3 based on a RK2918 board featuring a 1GHz Cortex A8 along with a front-facing 0.3Mpx Camera.

In case you are a user of said tablet and want to obtain root to get full control of your device to kick out unwanted crap that comes with the device, there's no way to get it done through normal means (meaning root-exploits) as the firmware is pretty air- and watertight. That being said - since 3Q released a v1.0.5_fix firmware update I managed to root the ROM, and also customize it for a bit, by modding the flash image.

So, here we go...

MEDIAFIRE (All downloadable items)
NOTE: All ROM 7zip's have the Rockchip USB Driver included as well as a copy of the changelog.txt containing details and flashing instructions. Everything you need for flashing is included.

As of 2013/02/02 the following ROM versions are up for consideration ...

3Q RC0710B v1.0.5 <date> custom-rooted
&#8226; The Stock ROM with an altered package selection
&#8226; RKAndroid Tool (for flashing the ROM) comes with RK29xxLoader 2.28 and a slightly remastered NAND partition layout.
3Q made a mistake there (at least on my tablet) as /mnt/sdcard only showed 512MB storage space instead of ~2GB
&#8226; See the text file for details and flashing instructions

3Q RC0710B v1.0.5 <date> custom-rooted-cwm
&#8226; Same as the "custom-rooted" but comes with ClockworkMod Recovery 6.0.1.5 instead of the default recovery
(Yes, you can flash CWM ZIPs with it)
&#8226; RKAndroid Tool (for flashing the ROM) comes with RK29xxLoader 2.28 and a slightly remastered NAND partition layout.
3Q made a mistake there (at least on my tablet) as /mnt/sdcard only showed 512MB storage space instead of ~2GB
&#8226; To easily get into the recovery you best issue "adb reboot recovery" from your computer
&#8226; See the text file for details and flashing instructions

3Q RC0710B v1.0.5 <date> rooted-clean
&#8226; The Stock ROM with in a clean state - also stripped off the Rockchip packages
&#8226; RKAndroid Tool (for flashing the ROM) comes with RK29xxLoader 2.28 and a slightly remastered NAND partition layout.
3Q made a mistake there (at least on my tablet) as /mnt/sdcard only showed 512MB storage space instead of ~2GB
&#8226; See the text file for details and flashing instructions

3Q RC0710B v1.0.5 <date> rooted-clean-cwm
&#8226; Same as the "rooted-clean" but comes with ClockworkMod Recovery 6.0.1.5 instead of the default recovery
&#8226; RKAndroid Tool (for flashing the ROM) comes with RK29xxLoader 2.28 and a slightly remastered NAND partition layout.
3Q made a mistake there (at least on my tablet) as /mnt/sdcard only showed 512MB storage space instead of ~2GB
&#8226; See the text file for details and flashing instructions

Since the ROMs are too large for Media Fire I had to split them into volumes. Download the the two files (ending with 7z.001 and 7z.002) and extract them with 7-Zip or any other program able to extract them.

There's also a copy of the genuine 3Q_RC0710B_24082012_v1.0.5.img firmware image (untouched) along with the required tools in case you want to flash back for whatever reason in the "Original 3Q Firmware Update v1.0.5-fix" folder. This one will restore the tablet back into the original NAND partition layout and also revert back to RK29xxLoader 2.20. You will find two packages there. One that is flashable through RKAndroid Tool (same as the custom ROMs) and another one that is flashable through RKBatchTool (not as convenient to use).

Note: If you need the one or another APK that has been removed from the customized ROMs you can find them inside the "Pulled APKs" folder at the MediaFire link from above. There's a collection of them out of the 201205 and 201208 3Q firmware.

If you just want to root the ROM and therefore avoid flashing the pre-rooted ROM, download the ROOT_v5_Windows.7z or ROOT_v5_Linux.tar.gz from the MediaFire link. Extract the archive. Before running the included .bat/.sh file make sure you have the Rockchip USB Drivers installed (Windows only), you activated "USB-Debugging" in the Developer options in System Settings and your tablet is connected to your computer through the USB cable.

Troubleshooting

Q: I want to just root my tablet but adb doesn't recognize my tablet [Windows / Linux]

adb doesn't know about Rockchip USB Vendor/Device ID by default. To make it work...

- On Windows (assuming your already installed the Rockchip USB driver):

• Open your user folder (C:\Users\your_username)
• Create a new folder and call it ".android" (without the quotes) <-- Yes, there is a dot in front of the name
• Get into the folder
• Create a new text file and call it "adb_usb.ini" (without the quotes)
• Open the text file in Notepad and insert "0x2207" (just this one line)
• Save the file
• In case you just used adb before issue "adb kill-server"
• On your tablet, in Settings -> Developer options, enable USB Debugging
• Connect the tablet to your computer
• Type "adb devices"
• Should work now

- On Linux

• Open your user folder (/home/your_username)
• Create a new folder and call it ".android" (without the quotes) <-- Yes, there is a dot in front of the name
• Get into the folder
• Create a new text file and call it "adb_usb.ini" (without the quotes)
• Open the text file in in gedit/kate/... and insert "0x2207" (just this one line)
• Save the file
• In case you just used adb before issue "adb kill-server"
• On your tablet, in Settings -> Developer options, enable USB Debugging
• Connect the tablet to your computer
• Type "adb devices"
• Should work now
  
  In case it doesn't show you any device or you get a "permission denied" you are missing a UDEV rule
• Open a Terminal
• Type "gksu gedit /etc/udev/rules.d/50-android.rules"
• In the text editor you insert ...
  SUBSYSTEMS=="usb", ATTRS{idVendor}=="2207", TEST=="/var/run/ConsoleKit/database", RUN+="udev-acl --action=$env{ACTION} --device=$env{DEVNAME}" <-- This is ONE line (for Ubuntu 11.04/Linux Mint 10 and later)!
• Save the file
• DISCONNECT the tablet, if it is plugged in
• Do an "adb kill-server" (if you just used adb for "adb devices")
• On your tablet, in Settings -> Developer options, enable USB Debugging
• Connect the tablet
• Type "adb devices" (without the quotes)
• Should work now.

Q: How do I get my tablet into "bootloader" mode (alias "USB JTAG mode") for flashing?

You can do that by two ways.

- Through adb (assuming your OS is configured correctly and you have adb / Google SDK installed)

• Connect the tablet with USB Debugging enabled
• Type "adb reboot bootloader" (without the quotes)
• The tablet will shut down and switch into bootloader mode
• DO NOT do this for fun! It's incredibly tricky to get the tablet back into normal mode.

- On the device itself

• Connect the charger to the tablet
• Connect the USB cable to JUST the tablet (NOT the computer yet)
• TURN OFF the tablet (long press the power button in Android and select "Shutdown")
• Start the RKAndroid Tool (in the RKAndroid folder)
• PRESS AND HOLD the VOL- Button while you press the Reset button with a push-pin or needle
• Screen stays black - no sound or anything (if the screen comes on with the 3Q logo - try again)
• Plug the USB connector into the computer and (given the driver is installed) RKAndroid tool will now say that the RKAndroid Rock Usb Loader has been found.
• DO NOT do this for fun! It's incredibly tricky to get the tablet back into normal mode.

In case of other problems or questions post here.

 

[kunosnv]

not working with my tablet... the combination of three pushed button not work for me... if i hold the power button on robot logo, nothing is happend...any idea.???

 

[EighthPieceOfNine]

not working with my tablet... the combination of three pushed button not work for me... if i hold the power button on robot logo, nothing is happend...any idea.???

Sorry for the inconvenience. I somehow got it wrong.

I revamped the OP post and included PDFs with Firmware Upgrade Instructions taken from the Prestigio MultiPad (which is actually the same tablet as the nextbook Premium 7SE which is actually the same tablet as the 3Q Q-Pad RC0710B).

On another note: If you just want to obtain root click the link to view all the files in the MediaFire folder. Then, depending if you're on Windows or Linux, download the "ROOT_v5" archive. Extract it and run the included .bat or .sh batch file to run a automated rooting procedure.

NOTE: You need to...

- ...have the Rockchip USB drivers installed.
- ...have USB-Debugging enabled in Settings -> Developer Options.
- ...have the tablet connected to your Computer via USB.

I also wouldn't hurt to connect the charger to make sure you don't run out of battery power along the way.

 

[Agramonis]

Sorry for the inconvenience. I somehow got it wrong.

I revamped the OP post and included PDFs with Firmware Upgrade Instructions taken from the Prestigio MultiPad (which is actually the same tablet as the nextbook Premium 7SE which is actually the same tablet as the 3Q Q-Pad RC0710B).

On another note: If you just want to obtain root click the link to view all the files in the MediaFire folder. Then, depending if you're on Windows or Linux, download the "ROOT_v5" archive. Extract it and run the included .bat or .sh batch file to run a automated rooting procedure.

NOTE: You need to...

- ...have the Rockchip USB drivers installed.
- ...have USB-Debugging enabled in Settings -> Developer Options.
- ...have the tablet connected to your Computer via USB.

I also wouldn't hurt to connect the charger to make sure you don't run out of battery power along the way.

I have a Qpad RC0710B tablet too, which isnt bootable anymore...i cant access the USB JTAG mode in the way, u described on point 5. The tablet is recognized by my Windows PC, but the RK AndroidTool.exe tells me: No Found RKAndroid rock usb.

Any help would be nice

 

[Beatsleigher]

Thanks dude! Worked like a charm, once you've gotten the download mode figured out

You just made a slight mistake (Which I noticed from the beginning). You have to press (and hold down) VOL -, hit the reset button, release the reset button and keep holding onto the VOL DWN button for a moment, or two

Other than that; great work! If you need some help with compiling a custom ROM, I know my way around Android pretty good (XDA Senior Member: familyguy59) send me a message over @ XDA, and I'll get back to you ASAP!

If you don't need my help, keep this thread updated and maybe post it on XDA aswell. We need more threads like this, for these rare devices

 

[EighthPieceOfNine]

Sorry for the very late reply ...

@Argramonis
Simply download either the customized version or the untouched Stock ROM version (take the "RKAndroidTool" one) from my MediaFire link above. The flash procedure no longer relies on RKBatchTool but on the much easier to use RKAndroidTool.

I updated the modified ROM version on 12/12/12 the last time, and apart from the one or another update for the system apps I also added a few new things like the swipe keyboard from Jelly Bean 4.2 and Emoji keyboard (which is a Japanese IME). The Emoji keyboard doesn't fully work, as I found out later on I forgot to include a few libs to make it fully work (to come in a new update). Simply check the text file - the changes and flash procedure are documented in there.

Now, to recover from a "total brick" (RK2918 devices cannot be totally bricked) do this:

- Download and unpack the Firmware (customized one or Stock - your decision)
- Start RKAndroidTool
- Check "Loader" (and do NOT change anything else!)
- Connect the charger to the tablet
- Connect the USB cable to the tablet (NOT to the computer yet!)
- Push the VOL- button and KEEP it pressed
- Push the Reset button
- Connect the USB cable to your computer

Now, if Windows is trying to install the flash driver (you can release the VOL- button now) point it to the provided Rockchip USB drivers.

Once the driver is installed ...

- RKAndroidTool will now say "Found RKAndroid Loader Rock Usb" (yes, lousy translation from Chinese).
- Click "EraseIDB" to repartition the eMMC
- Click "Run" and let it do it's thing

When the flash procedure has ended the tablet will automatically reboot - you can disconnect the USB cable - and enter the recovery to format the internal eMMC partitions.

@Beatsleigher
Didn't get very far with CM10/10.1 ... the device tree I borrowed from "vurrut" (@XDA) makes it possible to build, but several things simply don't really work as we don't have the sources of the drivers (GPU) nor the kernel sources.

Also, posting this Stock Mod to XDA is pointless. Oma7144 is already offering a bag of Custom ROMs for RK2918 devices at XDA (and a whole lot of other Android sites) ... ranging from CM9/10 to, obviously, AOSP 4.0/4.1 based builds. He even seems to work on a CM10.1 port, but as I worked out a whole lot of things don't work.

If you're still interested in trying to mess with a CM port for the RK2918 devices let me know.

 

[Beatsleigher]

Sorry for the very late reply ...

@Argramonis
Simply download either the customized version or the untouched Stock ROM version (take the "RKAndroidTool" one) from my MediaFire link above. The flash procedure no longer relies on RKBatchTool but on the much easier to use RKAndroidTool.

I updated the modified ROM version on 12/12/12 the last time, and apart from the one or another update for the system apps I also added a few new things like the swipe keyboard from Jelly Bean 4.2 and Emoji keyboard (which is a Japanese IME). The Emoji keyboard doesn't fully work, as I found out later on I forgot to include a few libs to make it fully work (to come in a new update). Simply check the text file - the changes and flash procedure are documented in there.

Now, to recover from a "total brick" (RK2918 devices cannot be totally bricked) do this:

- Download and unpack the Firmware (customized one or Stock - your decision)
- Start RKAndroidTool
- Check "Loader" (and do NOT change anything else!)
- Connect the charger to the tablet
- Connect the USB cable to the tablet (NOT to the computer yet!)
- Push the VOL- button and KEEP it pressed
- Push the Reset button
- Connect the USB cable to your computer

Now, if Windows is trying to install the flash driver (you can release the VOL- button now) point it to the provided Rockchip USB drivers.

Once the driver is installed ...

- RKAndroidTool will now say "Found RKAndroid Loader Rock Usb" (yes, lousy translation from Chinese).
- Click "EraseIDB" to repartition the eMMC
- Click "Run" and let it do it's thing

When the flash procedure has ended the tablet will automatically reboot - you can disconnect the USB cable - and enter the recovery to format the internal eMMC partitions.

@Beatsleigher
Didn't get very far with CM10/10.1 ... the device tree I borrowed from "vurrut" (@XDA) makes it possible to build, but several things simply don't really work as we don't have the sources of the drivers (GPU) nor the kernel sources.

Also, posting this Stock Mod to XDA is pointless. Oma7144 is already offering a bag of Custom ROMs for RK2918 devices at XDA (and a whole lot of other Android sites) ... ranging from CM9/10 to, obviously, AOSP 4.0/4.1 based builds. He even seems to work on a CM10.1 port, but as I worked out a whole lot of things don't work.

If you're still interested in trying to mess with a CM port for the RK2918 devices let me know.

I'm always trying to get into things

I decompiled the kernel as far as I could. I'm just stuck with the zImage.

I also tried flashing this CM10 port, of CyanoMod, and then flashed the stock kernel - No luck :/
It worked, except for the external SD card slot..

If you anything on that, let me know. But if you need help, I'll help where and when I can. But to be honest, I decided to give this back to my mum (I got the damn thing for Christmas) and I'm gonna get the Nexus 10, like I wanted. But I guess this would still be useful for people with this device..

 

[emmanuel.goldstein]

If you just want to obtain root click the link to view all the files in the MediaFire folder. Then, depending if you're on Windows or Linux, download the "ROOT_v5" archive. Extract it and run the included .bat or .sh batch file to run a automated rooting procedure.

NOTE: You need to...

- ...have the Rockchip USB drivers installed.
- ...have USB-Debugging enabled in Settings -> Developer Options.
- ...have the tablet connected to your Computer via USB.

I also wouldn't hurt to connect the charger to make sure you don't run out of battery power along the way.

Sorry,

this doesnt work, neither with windows (and correct driver) nor Linux.
In both cases the device isnt found.
Flashing procedure works fine but I like to keep the original ROMs, only
rooting ...

I dont like the custom firmware, because I cant find busybox and miss a file manager.

Any hints?

Thx in avance

emmanuel

 

[mwrsa]

OK, HI eveybody,
I just bought a RC0710B, too. But i tried the whole evening to get root access - without success. I don't know where to start.
OSes: Linux Mint 13 32bit, Windows 7 Enterprise 32bit, Windows XP Pro 32bit.

Rooting only: Neither Linux nor Windows found the tablet via ADB. Doesn't seem to exist. No device connected.
Flashing: Win7 starts its own driver install routine, installs a bunch, but not for some device like Q3M752B or something like that. Yet the available driver I downloaded via the link in the first post isn't suitable, won't be installed and used. WinXP has the same result. When I try to connect in recovery mode the tablet isn't recognized at all! No USB-Connected-Sound under either Windows!
Guys, I'm frustrated to the point of throwing that thing against a wall or out of the window. It's not my first Android device at all, had 3 phones and another tablet b4, but they all went smooth compared to this piece of junk. If you have no further ideas, the tablet will be returned within the next week - but only if I managed to keep my calm and not throw things against walls... (not seroius, only frustrated, sorry.)
Greetings, Martin

 

[EighthPieceOfNine]

OK, HI eveybody,
I just bought a RC0710B, too. But i tried the whole evening to get root access - without success. I don't know where to start.
OSes: Linux Mint 13 32bit, Windows 7 Enterprise 32bit, Windows XP Pro 32bit.

See below - to make adb recognize the tablet you need to create folder with a file. The Windows-way is in the reply to emmanuel.goldstein below, for Linux ...

Open your home folder
Create a .android folder
Get into the .android folder
Create a new text document and call it "adb_usb.ini"
Open the file in a text editor
Put "0x2207" (JUST this one line - WITHOUT the quotes!) into the file and save
Connect the tablet with USB Debugging enabled
"adb devices" should now show you the device

IF it doesn't show you a device or it says "permission denied" ...

Open a Terminal
Type "gksu gedit /etc/udev/rules.d/50-android.rules"
In the text editor you insert ...

SUBSYSTEMS=="usb", ATTRS{idVendor}=="2207", TEST=="/var/run/ConsoleKit/database", RUN+="udev-acl --action=$env{ACTION} --device=$env{DEVNAME}"

Save the file
DISCONNECT the tablet, if it is plugged in
Do an "adb kill-server" (if you just used adb for "adb devices")
Enable USB Debugging in the Settings -> Developer options
Connect the tablet
adb devices

Should work now.

Flashing: Win7 starts its own driver install routine, installs a bunch, but not for some device like Q3M752B or something like that. Yet the available driver I downloaded via the link in the first post isn't suitable, won't be installed and used. WinXP has the same result. When I try to connect in recovery mode the tablet isn't recognized at all! No USB-Connected-Sound under either Windows!

You know, the Rockchip USB Drivers are included in the ROM 7zip's and are actually working on Windows 7 x64 Edition as well as an Windows 7 32-Bit as I use them for RKAndroid Tool flashing every now and then.

Flashing instructions are included in the "Changelog.txt" that for download (and also contained inside the 7zip). In brief ...

You connect the charger to the tablet
You connect the USB cable to JUST the tablet (NOT the computer yet)
You TURN OFF the tablet (long press the power button in Android and select "Shutdown")
You start the RKAndroid Tool (in the RKAndroid folder)
You PRESS AND HOLD the VOL- Button while you press the Reset button with a push-pin or needle
Screen stays black - no sound or anything (if the screen comes on with the 3Q logo - try again)
You plug the USB connector into the computer and (given the driver is installed) RKAndroid tool will not say that the RKAndroid Rock Usb Loader has been found.

Follow further instructions as written down in the text file.

Sorry,

this doesnt work, neither with windows (and correct driver) nor Linux.
In both cases the device isnt found.
Flashing procedure works fine but I like to keep the original ROMs, only
rooting ...

Open your USER folder in Explorer. (C:\Users\your_username)
Create a .android folder
Get into the .android folder
Create a new text file and call it adb_usb.ini
Open the file for editing
Put "0x2207" (JUST this one line - WITHOUT the quotes!) into the file and save
Connect the tablet with USB Debugging enabled
"adb devices" (Command Prompt needs to run as ADMINISTRATOR!) should now show you the device

The "workaround" with the adb_usb.ini is not the fault of the rooting toolkit, it's adb that doesn't know of Rockchip devices by default.

I dont like the custom firmware, because I cant find busybox and miss a file manager.

Any hints?

Busybox (1.20.2) is included in the "custom-rooted", "custom-rooted-cwm", "rooted-clean" and "rooted-clean-cwm" version I have in my MF folder.

As for a Filemanager. If there's none, then how hard can it possibly be to start the Play Store, punch "ES File Explorer" into the search and install the app? You are complaining about something that isn't a problem to start with but just you having no frelling idea what you're doing.

EDIT: OP Post totally rewritten :holybible.jpg:

 

[mwrsa]

WOW, thank you! That was amazingly fast! Going to try right away.

I followed the given instructions in the .7z- files, and it's also been these included drivers that didn't work!

YAY! Rooting worked.
Now just one more question: The original Update provided on the vendor's HP, can I install it by unpacking it to the ext. SD, and it will then install automatically? I still won't get Windows to recognize the device... I'll have to do a reinstall of Win7 soon, so maybe that'll solve the issue.

Ok, just ran into another issue: One of my fav. games "Townsmen" runs with graphical errors (animated objects in the game have white background). Any1 had something similar, and a solution would be even nicer...
Thanks a bunch, Martin

 

[EighthPieceOfNine]

WOW, thank you! That was amazingly fast! Going to try right away. I followed the given instructions in the .7z- files, and it's also been these included drivers that didn't work! YAY! Rooting worked.

Funny enough the Rockchip drivers I put into the 7zip ROM archives work for me on Windows 7 (32-Bit AND 64-Bit) without any problems. Anyway, you solved it.

Now just one more question: The original Update provided on the vendor's HP, can I install it by unpacking it to the ext. SD, and it will then install automatically? I still won't get Windows to recognize the device... I'll have to do a reinstall of Win7 soon, so maybe that'll solve the issue.

Yes, you drop the ZIP package from 3Q, containing the v1.0.5-fix update, into the ROOT of your SD card (/mnt/sdcard) and it should recognize the update. KEEP IN MIND that you have to ROOT AGAIN after you applied the update!

Ok, just ran into another issue: One of my fav. games "Townsmen" runs with graphical errors (animated objects in the game have white background). Any1 had something similar, and a solution would be even nicer... Thanks a bunch, Martin

This is a known problem on this tablet (and its countless "RK2918" clones). The Vivante GC800 drivers don't really support all possible hardware acceleration functions of Ice Cream Sandwich / Jelly Bean. Several games either give graphical errors OR even crash (i.e. Angry Birds). Same for Google Earth ... v7.0.0 was the last version to work on the RC0710B, newer versions will happily crash on startup with a rather nasty EGL (OpenGL) error.

EDIT: As a bit of a more in-depth explanation: The RK2918 devices have actually been designed as Android 2.3 'Gingerbread' was the hot thing in town. While the devices were updated to run Android 4.0 'Ice Cream Sandwich' the GPU drivers didn't get a "fully ICS compatible" refresh. They work to some extend, but, unfortunately, cause the one or another problem when it comes down to games or other apps that make use of specific functions.

The problem with the GPU drivers can't be solved as Yifang (the manufacturer of the tablet) as well as 3Q refuse to make the source code for Android available (they are violating the GPL on a massive scale as they are not even publishing the kernel sources).

In short: There's nothing that can be done to resolve the problem.

 

[mwrsa]

Many thanks, EighthPieceOfNine! I had already done a clean wipe and made everything ready to return the tab... Now almost everything I need is working (almost: see below).

Funny enough the Rockchip drivers I put into the 7zip ROM archives work for me on Windows 7 (32-Bit AND 64-Bit) without any problems. Anyway, you solved it.

I haven't given another try yet. Nevertheless I don't need it anymore, really.

Yes, you drop the ZIP package from 3Q, containing the v1.0.5-fix update, into the ROOT of your SD card (/mnt/sdcard) and it should recognize the update. KEEP IN MIND that you have to ROOT AGAIN after you applied the update!

Well, it even works to drop the .img file inside the .zip, and did in fact work flawlessly. Rooting afterwards went smooth again, just as it should.

This is a known problem on this tablet (and its countless "RK2918" clones) [...] In short: There's nothing that can be done to resolve the problem.

Doesn't bother me too much. Thank you for the detailed explanation! Now what still doesn't work (an I've only found out today): Charging via the µUSB- Port! Can you confirm this? That would be another serious issue, I can't be forced to (and certainly won't) buy two more chargers (home, work, car)?!? This could also be ICS- related, as far as I've already read about the issue. And it won't last me over a whole day without charging... Gby, Martin

 

[EighthPieceOfNine]

Now what still doesn't work (an I've only found out today): Charging via the µUSB- Port! Can you confirm this? That would be another serious issue, I can't be forced to (and certainly won't) buy two more chargers (home, work, car)?!? This could also be ICS- related, as far as I've already read about the issue. And it won't last me over a whole day without charging... Gby, Martin

Charging the tablet via the µUSB port is NOT possible! This is NOT a "serious issue" but "intentional by design".

Before you now ask about the "Why?" ... here's yet another explanation about how things relate to this ...

If you take the charger and turn it around you will notice that it shows an output of +5V at a max. of 2000mA (=2 Ampere). Now, the USB port on a computer does ONLY support devices taking no more power than 500mA (=0.5 Ampere) PER USB-plug. Since the tablet needs "a wee bit" more juice to actually charge the battery it is therefore totally impossible to charge the tablet from the computer through the µUSB port.

If you want to spare you the extra charger, there are two "home brew" ways you can consider (that's what I actually did as I have two devices that need to be charged through their own external charger) ...

Option 1: Get a USB charger station.
This means the charger stations having 2-4 normal sized USB jacks to charge devices. Seeing you're from Germany... simply order yourself the connector you insert into the tablet from Conrad or Reichelt along with a 2-wire cable and a USB plug (or simply crash by the store to get the parts). The idea is to create a charger cable that has a USB connector rather than the charger on the one end and the plug that goes into the tablet on the other end. That way you can charge the tablet from a charger station - though be WARNED to NEVER plug this cable into a computer or laptop! You may overload the USB port and cause irreparable damage to the motherboard!!!

Option 2: Tap into a +5V line in the computer and make yourself a connection port.
The red wires of the power supply inside your computer are +5V and the black ones are GND (Ground). Like above get yourself the power jack the goes into the tablet, some 2-wire cable and a Molex power plug (so you can connect the cable to one of the plug usually powering CD/DVD or old PATA drives). That way you can use your computer to charge the tablet when it is turned on without the fear of overloading anything ... the power supply should be able to spare the 2 Amp for charging the tablet. The only thing you HAVE to keep in mind is that you MUST NEVER short the power line and also prevent it from touching the metal casing of the computer. IF you short the line (i.e. you spill water/soda/... over the connector or you short it past the computer case) the power supply will power off (lousy engineered power supplies may even take a damage).

Simply use your imagination and MacGyver-ism to create yourself a worthwhile solution.

What I did was to create my own "charging station" by using a old "AT board" power supply (you know, the power supply that powered the old motherboards with the large 5-pin keyboard connector).

I got myself a bunch of USB extension cords, clipped off the connector that usually goes into the computer, desoldered the whole cables from the printed board of the power supply, soldered the +5V and GND wires of the extension cords in and modified the power switch to be inside the power supply casing. I have 10 USB ports coming out of the power supply to charge USB devices with (though it doesn't work with devices that are "locked in" to their own USB charger due to the charger having a chip inside of it to "tell" the device it is connected to its genuine charger).

 

[mwrsa]

Thanks again, as I wrote before, I already read a bit into this issue (imho still a clear desig fail , since there are already other USB solutions out providing up to 2A via the standard USB ports of various sizes, but never mind.)
What troubles me most is that I can't simply use one of my phone chargers (1,5A output) or my car charger (2A output), just because this tab uses the small round (2mm? 2,5mm? gonna measure!) plug to draw its power from.
Anyway you confirmed that it's simply not possible by design (and therefore no malfunction), and as you wrote I'm going to use my "imagination and MacGyver-ism" (I love this!), but just in this way as to make (or maybe even buy) two cables offering an USB A plug on the one side and the small round plug needed for the tablet on the other. Should do the thing, not only on a charger station, plus is the simplest way I can think of.
Option 2 is no longer possible for me: There are only laptops left around me, I seriously doubt to find one of those PSUs in one of my hardware boxes I'm still storing for nobody knows why.


All right, good night, I'm off looking for cables...