[G Tablet Q&A, Help & Troubleshooting] djab67:
GUIDE - Restore G Tablet after a Failed Recovery Mode "update.zip"

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Table of Contents

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GUIDE CHAPTERS

A ) CAUTION!!!!!

B ) GUIDE INFORMATION

C ) THANK YOUS!!!

D ) VALUABLE INFORMATION

E ) ALTERNATIVE SOLUTIONS

F ) BACKGROUND

G ) PROBLEM DESCRIPTION

H ) FAILED ATTEMPTS

I ) KEY TERMS & NOTES

J ) SYSTEM AND UTILITIES USED

K ) SOLUTION STEPS

L ) FINAL THOUGHTS
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APPENDIX CHAPTERS

M ) APX MODE AND NVFLASH TIPS

N ) WINDOWS USER NOTES
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A ) CAUTION!!!!!

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The steps presented in this guide are aggressive. You do not need a microSD card in the G Tablet, so it should be removed before beginning to prevent an unintended impact. Also, one of the steps involves partitioning the internal SDcard memory, all the data stored there will be wiped.

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B ) GUIDE INFORMATION

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This guide is divided into chapters which were outlined above in the Table of Contents. The chapters are broken down into one or more sections and/or steps. I believe reading through the entire guide at least once to develop understanding is the first step to potentially restoring your G Tablet. However, if you are already familiar with the various tools and methods used below you are welcome to jump right into the "K ) SOLUTION STEPS" chapter.

My objective in this guide was to provide all the steps I used to successfully restore the G Tablet. There are probably unnecessary steps in these instructions. You are more than welcome to skip any steps you deem unnecessary.

As you read through the guide you will notice that three main "tools" are used in various steps. The tools used are nvflash, ADB, and Recovery (both Stock and ClockWorkMod ). nvflash is the only tool you need to get started assuming you can put the G Tablet into APX mode (instructions on entering APX mode are in this guide).

Note that there are alternatives to accomplish the tasks where I used ADB. If you know or find another way to accomplish the "ADB" tasks, go ahead and substitute with the other method. Again, my objective was to detail the exact steps I used and ADB was one of my tools.

Although I cannot assume this guide will work for anyone else, if you happen to be in the same position as I was, then hopefully it will work for you too. Even if you are not successful, you might take away a piece that eventually leads to your solution. That is what happened for me by carefully following the recovery steps others so graciously posted. Of course there is a risk that matters could become worse.

If for some reason my links fail or are removed, you should be able to find the needed files and information with some forum and/or google searching.

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C ) THANK YOUS!!!

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Big Thank Yous to all the hard working developers who made the apks, scripts, and roms I used to restore my tablet. And just as important, the documentation they make readily available.

Special thanks and acknowledgement; roebeet, bekit, goodintentions, rr5658, Mp4, and Titanium Track's.

And thank you to the people who moderate and make sites like slatedroid.com and xda-developers.com possible. They are both invaluable sites to me.

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D ) VALUABLE INFORMATION

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Viewsonic GTablet for Dummies - Extremely helpful site. I learned the most from this site (belongs to member goodintentions) and roebeet's postings.

Viewsonic G-Tablet Disaster Recovery - Read up. Especially the topics posted by roebeet.

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E ) ALTERNATIVE SOLUTIONS

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The solution that worked for me is not the only working solution available. In fact, depending on your situation, one of the alternatives may be a better solution for you. Thank you to all who have posted solutions that worked! I read a lot of posts and all of the information contributed to what finally worked for me. The purpose of this post is just to add another series of steps and give decent detail, hoping that they help someone else. Here are a few other solutions you should review to see if they would be better for your situation:

Review the "Code" levels on this site. Viewsonic GTablet For Dummies

See post by K J Rad. A much more streamlined process and no ADB required. Tablet will not turn on - Post #114

See post by boogiebear575. A variation of K J Rad's process. modifcation of K J Rad's recover worked!

See post by burbley. Only requires use of nvflash. NO Birds NO recovery - Post #20

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F ) BACKGROUND

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A day after receiving the Viewsonic G Tablet from Woot, I was ready to get a custom ROM flashed on it. Even before placing the order I had a ROM chosen, CyanogenMod's 7.0.3-Harmony with Google Apps version 20110613.

I need to state something upfront. I like CyanogenMod's ROMs and greatly appreciate all they do in the android community. It was my favorite ROM on my Droid Incredible (no longer my primary device) and the ROM is working well on a friend's Viewsonic G Tablet (that tablet was ordered from a different retailer and a month or so before mine). I do NOT / will NOT blame any developer/themer/modder when something I chose to flash messes up the device. My choice, my risk, my consequence.

I followed CyanogenMod's “Viewsonic G Tablet: Full Update Guide” exactly:

installed ClockworkMod_Gtab_v08.zip (renamed to update.zip) with Stock Recovery

installed CyanogenMod and Google Apps zip files with ClockworkMod Recovery

I wasn't going to use ROM Manager for the install even though it was an option presented. I have done a lot of ROM flashing on my Droid Incredible and now Thunderbolt and have learned I get the best results when flashing from Recovery.

One step I did not do was backup. I should have used ClockworkMod and/or nvflash (didn't know about nvflash yet) to do a backup, but figured since I had made no changes out of the box, why bother? Had I done a backup, I might have saved hours upon hours of trouble shooting. Live, fail, and learn.

Note: This guide does not cover nvflash backup, but I included a couple of links in the "M ) APX MODE AND NVFLASH TIPS" chapter.

Once the installs finished on ClockworkMod, I wiped cache, factory reset/user data delete, and then selected system reboot. I soon realized I had a problem.

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G ) PROBLEM DESCRIPTION

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No matter what I did, I could not get the tablet to boot. No combination of pressing and holding keys would boot the tablet into any mode. All I could get was blank screen. (Note: Early on in this process I knew nothing about APX Mode.)

Unfortunately, I did not check the original stock bootloader version. I assume it was 1.1, but I really don't know. I read a few forum disaster postings that seemed to be from flashing Woot purchased G Tablets.

I think I had APX Mode available the whole time. I was well into the process of trying to restore the tablet before I started to understand APX Mode. At one point I did try a “shorting the circuit” solution, so it is possible that I had lost APX Mode too and got it back after the “shorting”. Although I am pretty confident I had APX Mode available the whole time.

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H ) FAILED ATTEMPTS

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I spent many hours trying different solutions posted on various forums. Although no one solution fixed my tablet, I believe working through them resulted in the steps that led to a working solution for me.

Brief descriptions of solutions tried (I even combined some in different patterns to find what would work):

nvflashing back and forth between 1.1 and 1.2 based ROMs (stock and custom)

nvflashing froyo, gingerbread, and honeycomb ROMs (some stock, mostly custom)

“shorting” the internal connections

fully draining the battery

As it turned out the more aggressive attempts by “shorting” internal connections and draining the battery were probably not really needed in my case. These appear to be techniques for getting APX Mode back. I don't think I ever lost APX Mode.

I spent at least 30 hours before finding the right combination of steps that restored the tablet. It all came together the morning of July 4, 2011 (Happy Birthday U.S.A.)

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I ) TERMS & DEFINITIONS

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APX Mode - Hold down “Volume minus” key and press “Power” key for a couple seconds.

APX Mode check - APX Mode and the USB connection with the computer can be checked by typing lsusb in a Linux terminal window. The “Bus Device” will include a line containing “ID 0955:7820 NVidia Corp.” if the tablet is in APX Mode.

Recovery Boot - Hold down “Volume plus” key and then press and hold “Power” key until Recovery is booted (does not matter whether Stock or ClockworkMod recovery is installed).

Volume Keys - I was messed up by the volume key plus and minus placement at first (I am new to tablets). When holding the tablet as portrait with the navigation buttons (Home, Menu, Back, and Search) at the bottom, the Volume minus key is closest to the top and the Volume plus key is farthest from the top.

SDCARD - I used the tablet's internal SDCARD for the entire process. No microSD card was in the tablet's slot.

Hash - I strongly recommend checking a downloaded file's hash when the checksum is provided. If not provided, then at least check to see if the downloaded file is the same size as the one posted.

Terminal Commands - Terminal commands (including adb shell commands) are bold-green for clarity. Example: ./nvflash_complete.sh

File Paths/Names - File paths and names are bold-blue for clarity when they are not part of a command. When file paths/names are part of a command they will be bold-green.

Linux User - It is assumed work is performed as a normal user with sudo privileges and from the user's /home/user/ file location.

Shell Scripts - Note the . (dot) and / (forward slash) in front of the script commands (the ones that have the extension .sh). The dots are sometimes hard to see.

USB Debugging - Whenever you are successful in reaching a full boot into the tablet's OS, one of your first tasks is to go into Settings-|Applications-|Development and make sure USB debugging is on.

nvflash - instructions below cover downloading and what to do with the program and shell scripts.

adb – Android Debug Bridge (adb) will be used below. It is assumed adb is already set up on your computer. For reference - I used the instructions at this link to setup the Android SDK without eclipse on my Linux Mint Debian computer - Linux Mint Forums • View topic - How To: Android SDK/ADB setup for lmde *Updated 1/29/11*

Methods - If you haven't already, read up and learn about APX Mode and Recovery Mode. They are different and the steps below use one or the other for flashing/installing.

READ - Read this entire post and read the referenced, linked information

before

you start executing the steps.

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J ) SYSTEM AND UTILITIES USED

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Computer -

OS – Linux Mint Debian (32 bit)

Desktop Environment - Gnome

Gedit – used for editing shell scripts

Archive Manager – used for extracting

Terminator – terminal program that allows multiple running sessions within the same window pane.

Nautilus 2.30.1 – file browser, used for moving files around, selecting scripts for editing, checking file permissions, and setting up directories

nvflash

adb

Viewsonic G Tablet -

Purchased from Woot on June 28, 2011

Model - UPC300-2.2

Note to windows users - The steps in this guide are not exclusive to any particular OS. The appendix at the very bottom lists the different downloads needed and other differences when using a windows computer.​

(continued in next post)