[rom] [twrp] sm-t290 & sm-t295 [discussions & help thread]

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gcrutchr

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Jun 11, 2009
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Use this BL file when upgrading to T295XXU4BUC8.
then flash the root file attached ...
P.S.
If you have already updated the firmware completely, that is, the bootloader is already 4 versions, then I don’t know yet, because I don’t risk updating like that ...
Perhaps this is a dead end :(
Thanks, I will try it. And, yes, I have already updated.
 

Talich52

Senior Member
Dec 24, 2010
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Thanks, I will try it. And, yes, I have already updated.
This is bad ... Samsung does not allow downgrading the bootloader, that is, version 4 cannot be replaced with version 3 of Android 9. I tried changing the aboot.mbn file via TWRP - the result is now the device is like a brick and so far the bootloader has not been restored. I bought a new one of the same T295, but I don’t do this and I warn everyone ...
 
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gcrutchr

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Jun 11, 2009
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This is bad ... Samsung does not allow downgrading the bootloader, that is, version 4 cannot be replaced with version 3 of Android 9. I tried changing the aboot.mbn file via TWRP - the result is now the device is like a brick and so far the bootloader has not been restored. I bought a new one of the same T295, but I don’t do this and I warn everyone ...
Thanks. I have 2 T295s. One is on BUC8, one is on BUC3. I downloaded a program to view/change the contents of the vbmeta.img file. I will try to change some of the info to get it to work.
 
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Talich52

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Dec 24, 2010
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I downloaded a program to view/change the contents of the vbmeta.img file. I will try to change some of the info to get it to work.
Hmm ... the vbmeta.img file patches Magisk, this file is patched by MagiskManager version 22006 (Canary)
The file has the same size as the stock, and earlier after the patch the file was only 256 bytes
 

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ahotcash21

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Apr 11, 2021
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Device: Samsung Tab A8 SM-T295
Android version: 10
Baseband version: T295XXU3BUA5
Kernel Version: 4.9.186-perf-18961046
Build number: QP1A.190711.020.T295XXU3BUA5
SE for Android Status: SEPF_SM-T295_10_3007 (29-01-2021)
Service Provider SW ver: SAOMC_SM-T295_OJM_XVF_QQ_0006, R9WR307M2TJ, XFV/XFV

I have flashed and rooted Android 9 successfully, but recently the newer SM-T295 came with Android 10. So the current way doesn’t work anymore – once I try it, although the tablet seems to be on, the screen is black or like a blue and you cannot see anything on the screen.

The above are the details of the current tablet I am trying to flash and root. I have followed the processes posted by gcrutchr and Talich52. I have even used the same ROMs (T295XXU3BUC3 , T295XXS3BTL4 - T295OJM3BTI1/T295XXU3BTI3) and some others.

But the moment I flash the Android 9 BL_T295XXS3ATB2 or aboot_vk_T295XXS3ATB2.tar files provided – the screen goes black and I cannot see anything and cannot continue to even flash the TWRP file. I have tried multiple times thinking I am not restarting properly etc, but cannot get it to work.

Can you perhaps give me some assistance – not sure what I am doing wrong…I would really appreciate it...

Thanks
 

Talich52

Senior Member
Dec 24, 2010
493
261
Device: Samsung Tab A8 SM-T295
Android version: 10
Baseband version: T295XXU3BUA5
Kernel Version: 4.9.186-perf-18961046
Build number: QP1A.190711.020.T295XXU3BUA5
SE for Android Status: SEPF_SM-T295_10_3007 (29-01-2021)
Service Provider SW ver: SAOMC_SM-T295_OJM_XVF_QQ_0006, R9WR307M2TJ, XFV/XFV

I have flashed and rooted Android 9 successfully, but recently the newer SM-T295 came with Android 10. So the current way doesn’t work anymore – once I try it, although the tablet seems to be on, the screen is black or like a blue and you cannot see anything on the screen.

The above are the details of the current tablet I am trying to flash and root. I have followed the processes posted by gcrutchr and Talich52. I have even used the same ROMs (T295XXU3BUC3 , T295XXS3BTL4 - T295OJM3BTI1/T295XXU3BTI3) and some others.

But the moment I flash the Android 9 BL_T295XXS3ATB2 or aboot_vk_T295XXS3ATB2.tar files provided – the screen goes black and I cannot see anything and cannot continue to even flash the TWRP file. I have tried multiple times thinking I am not restarting properly etc, but cannot get it to work.

Can you perhaps give me some assistance – not sure what I am doing wrong…I would really appreciate it...

Thanks
Interesting case ;) Is the bootloader unlocked? If not, first unlock the bootloader, and then change it to 9 android...
 

ahotcash21

Member
Apr 11, 2021
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0
ok, I gonna try that and will get back to .... thanks...
Hi, I tried that and still it did not work. After flashing android 9 - the tablet display is grey-blue and doesn't display anything. Even so, I managed to get back into download mode and flashed android 10 without BL - is showed success but still the screen is grey-blue/black - and displays nothing.
And like previously mentioned, the tablet is on - but the display is not showing anything - any idea why the display would not show anything?

Thanks
 

Viggen66

Senior Member
Mar 22, 2009
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Hi, I tried that and still it did not work. After flashing android 9 - the tablet display is grey-blue and doesn't display anything. Even so, I managed to get back into download mode and flashed android 10 without BL - is showed success but still the screen is grey-blue/black - and displays nothing.
And like previously mentioned, the tablet is on - but the display is not showing anything - any idea why the display would not show anything?

Thanks
I have same issue, flashing twrp, but without new bootloader, screen always black, and working in the background, but was able to successful flash stock rom and works again.

Who do you check what is your version of bootloader to downgrade? Probably this new bench of tablet have new protection
 

Talich52

Senior Member
Dec 24, 2010
493
261
Hi, I tried that and still it did not work. After flashing android 9 - the tablet display is grey-blue and doesn't display anything. Even so, I managed to get back into download mode and flashed android 10 without BL - is showed success but still the screen is grey-blue/black - and displays nothing.
And like previously mentioned, the tablet is on - but the display is not showing anything - any idea why the display would not show anything?

Thanks
I recommend the following actions:
1) flash full firmware 10 android, that is, all 4 parts.
The device should start up normally.
2) Lock the bootloader - this is done in the same way as unlocking, but in the reverse order.
3) flash 9 android, parts BL, AP, CP, CSC (not HOME_CSC), that is, with data reset, otherwise rollback is impossible.
4) if the device starts successfully, then unlock the bootloader.
5) flash 10 android, but no BL file

P.S. If the bootloader was unlocked on Android 9, then it will remain unlocked on Android 10 ...
My second device T295 has a production date of 10/10/2020 and I don't see any such problems ...
 
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Viggen66

Senior Member
Mar 22, 2009
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How can I downgrade my T290 to Android 9, which came with latest firmware T290XXU3BUB2? How to tell which bootloader version my tablet is? With Android 9 is easier to root right?
 
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Talich52

Senior Member
Dec 24, 2010
493
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How can I downgrade my T290 to Android 9, which came with latest firmware T290XXU3BUB2? How to tell which bootloader version my tablet is? With Android 9 is easier to root right?
To return to android 9, flash android firmware 9, say T290XXS3ATF1
and necessarily with a part of the CSC (not HOME_CSC), that is, with a data reset, since otherwise a rollback is impossible.
For detailed information about the current firmware, see the Phone Info program from the market.
Rooting on Android 9 is easier, you only need to unlock the bootloader, you don't need to change it.
Next, install the root file, where the patched Magisk boot.img & vbmeta.img. You will find the files for rooting in my messages ...
I will attach the apk-file of the Phone Info program:
The file for rooting T290XXS3ATF1 is posted in the message:
 

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Viggen66

Senior Member
Mar 22, 2009
724
85
Hi, I tried that and still it did not work. After flashing android 9 - the tablet display is grey-blue and doesn't display anything. Even so, I managed to get back into download mode and flashed android 10 without BL - is showed success but still the screen is grey-blue/black - and displays nothing.
And like previously mentioned, the tablet is on - but the display is not showing anything - any idea why the display would not show anything?

Thanks
Only way to get image on my tablet was installing the stock firmware T290XXU3BUB2, after that got image, and tablet worked again, probably this new version has enhanced protections for twrp
 

Viggen66

Senior Member
Mar 22, 2009
724
85
Tried flashing full android 9 with locked bootloader, same crap, black screen with no image, wondering which new protection is this which samsung added
 

Talich52

Senior Member
Dec 24, 2010
493
261
Tried flashing full android 9 with locked bootloader, same crap, black screen with no image, wondering which new protection is this which samsung added
I have a device with a T295 modem, but the firmware of the T290 model also includes a CP modem file. Moreover, if I installed a modem for a new bootloader T295XXU4BUC7, then the previous T295XXU3BUA5 modem is flashed successfully, but the device does not boot (bootloop) :(
Hence the recommendation is to flash the 9 android again, except for the CP modem file, that is, use the BL, AP, CSC files (no HOME_CSC).
Good luck!
 
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  • 4
    You guys are fast to edit a someone's speech but can't clean this thread up?
    If you have issues with posts in this thread, use the Report button. The only problems I've seen thus far have been your posts - you're rude, demanding, and abrasive. Perhaps you should take a moment to familiarize yourself with the Forum Rules linked in my signature before you continue posting in such a manner.
    3
    Is a TWRP root version of this being worked on? Having TWRP would be great as it provides a lot of great features.

    I was able to root my SM-T290 using Magisk Manager and a collection of random instructions from different parts of the internet.

    The purpose of rooting my device was to operate Kali Nethunter and its modules in which root access is needed.

    I wanted to provide the steps I took to root my device. Disclaimer: PROCEED AT YOUR OWN RISK! I AM NOT RESPONSIBLE IF YOU BRICK YOUR DEVICE OR DONT KNOW HOW TO RECOVER FROM A SOFT BRICK.
    I do not take credit for this, I am simply aggregating what I found during my experience of trying to root my device.

    Furthermore, at the time of writing, doing all the steps will have your ctsProfile set to false, which I believe means you can't do certain banking functions, etc. I've tried numerous guides online to attempt to fix it, but none have worked. They all just unroot the device and I have to do a quick root with Odin since I saved the files from all the steps.

    Needed Items:
    • Cable to connect SM-T290 to PC
    • microSD card
    • Ability to connect microSD card to a PC
    • Paperclip or pinhole stick to open slot on SM-T290
    • Linux (VM is not needed if you don't have one. You can use the Windows Linux Subsystem & obtain Ubtunu from Microsoft Store)
    • Stock Firmware

    DRIVERS

    Install the drivers for your device on your computer. You can google this or connect it to the computer and let it install them on its own.

    UNLOCK BOOTLOADER & USB DEBUGGING

    Before you can do this, you need to enable developer options.

    1) Go to Settings
    2) Go to About tablet
    3) Go to Software Information
    4) Click on Build Number repeatedly. You will see a message at the bottom saying X amounts of taps remaining to enable it
    5) Go back to Settings
    6) At the bottom, you'll see Developer options, click it
    7) Locate OEM Unlocking and enable it. Accept the warning is given, if it is shown
    8) Scroll down and locate USB debugging and enable it

    You've now enabled OEM Unlock & USB debugging.

    9) Turn off the device.
    10) Connect the USB cable to the computer. Do not connect it to the device yet
    11) Press and hold the Up & Down volume buttons at the same time
    12) While holding them down, connect the other end of the USB cable to the device
    13) A warning screen should show up prompting about the risk of unlocking the bootloader
    14) Press and hold (Long Press) the Up Volume button

    Your bootloader should now be unlocked. You can confirm if this is the case as every time you boot the device, you'll receive a bootloader warning.

    Download Stock Firmware

    You need a copy of your stock firmware. First, you need to look up what version you are using.

    1) Go to Settings
    2) Go to About tablet
    3) Go to Software information
    4) Find Build Number and write down the portion after the bulk of numbers, ie. T290XXS3ATC2
    5) Go to <I can't enter a URL since I don't have 10+ posts>. Google SFirmware Samsung SM-T290 (I do not own this site nor do I know how the firmware is obtained. Due to this, I don't store anything personal on the rooted tablet)
    6) Find the build number matching your tablet and its country
    7) Download the files to your computer

    File Modification Needed Towards Root

    1) Unzip the file downloaded
    2) On your Linux VM or Linux Sub-Windows System, go to the folder where the extracted files are at
    3) Find the AP*.tar.md5 file
    4) Extract its contents using the following command: tar -xvf <filename>
    5) Decompress the following files from the extracted AP tar file: boot.img.lz4, recovery.img.lz4, and vbmeta.img.lz4, using the following command: unlz4 <files>
    6) Add the newly decompressed files from the last step into a new tar file, using the following command: tar -cvf pre-processed.tar <files>
    7) Copy the newly created tar file named pre-processed.tar onto a microSD card
    8) Insert the microSD card into the tablet
    9) Using Files, copy pre-processed.tar from the microSD card to the Downloads folder on the Internal Storage. (This step may be optional, but I did this anyway).
    10) Install Magisk Manager on the tablet. The software can be found here: <I can't enter a URL since I don't have 10+ posts> Google Magisk Manager
    11) Open Magisk Manager
    12) You will see it says Magisk is not installed, to the right there is an Install button, click it.
    13) You will be prompted if you want to install it now, click Install.
    14) Navigate to the pre-processed.tar file in Downloads and let it do its thing.
    15) It will process and say it generated a new file, which can be found in the Downloads folder called something like magisk-patched.rar
    16) Copy that file back to the microSD card
    17) Copy that file to your computer
    18) Extract its contents using the following command: tar -xvf post-processed.tar
    19) Go into the new directory containing the extracted content and be sure to add post_ in front of each file there
    20) Copy the files to the AP folder which you created the pre-processed.tar files from.
    21) For post_boot.img and post_recovery.img (not post_vbmeta.img), perform the following command in Linux for each:
    Code:
    dd conv=notrunc if=<POST_PROCESSED_EXTRACTED_*.img_FILE> of=<PRE_PROCESSED_EXTRACTED_*.img_FILE>
    22) Delete the post_boot.img file to prevent any confusion
    23) Delete the post_recovery.img file to prevent any confusion
    24) Delete the vbmeta.img (original) file. Find post_vbmeta.img and rename to vbmeta.img
    25) Create new AP tar file with all original extracted files in the AP folder, except replace the following:
    Code:
    boot.img.lz4 -> boot.img (of= file from last step)
    recovery.img.lz4 -> recovery.img (of= file from last step)
    vbmeta.img.lz4 -> vbmeta.img (from post-processed.tar generated by Magisk)

    Remember the command to create a .tar file is tar -cvf AP-Patched.tar <files>

    Odin & Root

    1) Download Odin if you don't have it already have it from <I can't enter a URL since I don't have 10+ posts> Google Odin3
    2) Boot your tablet into download mode. (Device Powered Off -> Power + Up Volume -> Recovery Mode -> Download Mode)
    3) Connect your tablet to your computer
    4) Open Odin and load the files one by one from the downloaded stock firmware. The only difference should be the AP file which should be the newly created AP-Patched.tar file.
    5) Start it & let Odin do its thing.
    6) Once it's done and the device has restarted, you can check Magisk Manager.
    7) If you see Magisk is up to date with a checkmark, congratulations, you now have root access.

    Hope this helps folks out as I spent about 2-3 days trying to figure everything out.
    3
    I too have this same black screen problem. I just recently posted over on the TWRP 3.5.1 thread here. How I got into this mess is that I tried flashing the TWRP v3.5.1 to my brand new Costco (link) SM-T290NZKCXAR using Odin3 vs 3.14.4 by checking the AP box and putting the TWRP v3.5.1 in the original top post in text area. When it finished successfully, my screen turned on (backlight illuminated) but black and vibrates when touched. If I turn it off by holding the power button, it turns on again to this same state. Odin v 3.14.4 seems to recognize it as COM 1 sometimes (and when it does, Windows shows it as a device in the device manager). When I attempt to hold the power, vol up and vol down buttons to reboot into download mode (perahps im not doing it correctly) it will "reboot" into the same black screen/illuminated background state but without Windows or Odin detecting it. If it helps my serial number begins with R9 and I just bought it from Costco yesterday ($111 with tax / on sale for $99) Any thoughts or ideas appreciated and happy to answer questions or provide more details. thx in advance!
    Turn off tablet.
    Connect usb cable to PC, but NOT to tablet.
    Press vol up + vol dn keys and hold them down.
    Insert usb cable into table while holding down keys.
    You should see a screen with text on it. Release keys.
    Follow directions on screen.
    2
    Here is a TWRP test build for the SM-T290 model only:

    Please test this out and give me feedback. Thank you!
    https://github.com/secretwolf98/project/releases/download/vTWRPb1t1/twrp.tar
    2
    Well, the SM-T290 can handle ROMs. But only Project Treble enabled GSIs will work on it. So far, I’m trying to figure out how it could be installed through Odin without TWRP. Because Samsung devices doesn’t have a proper bootloader to be able to accept fastboot commands.

    Actually, my T295 has a fastboot option. I discovered it by accident. I modified the system.img file (new bootani*.qmg files). But, it would not boot. I got an error msg. When I did the vol up + vol dn + pwr keys, I ended up in a menu that showed a fastboot selection. I tried selecting it, but since my system.img would not boot, I could not get into it. Nor could I get into recovery, etc. So, I selected power down. After tablet was off, I could get into download mode.