[ROM][SM-T350][UNOFFICIAL][crDroidAndroid-10.0][v6.15][ANDROID 10] Galaxy Tab A 8.0

retiredtab

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Nov 16, 2017
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TWRP 3.5.0 for the SM-T350 added to the main post.
DO NOT USE TWRP 3.5.0.10 until nubianprince and I discuss. I found one bug and another potentially serious one that will cause a boot loop and you will have to revert back to stock to fix. For the latter, more research is required to figure out what's going on.

Use 3.3.1, it's what I have used to flash the T350 over 100 times during development.

I already sent nubianprince a PM, but this will take some time to figure out. I know he's busy and 3.3.1 works fine so there's no urgent need to fix this right away.
 
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bluenote73

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DO NOT USE TWRP 3.5.0.10 until nubianprince and I discuss. I found one bug and another potentially serious one that will cause a boot loop and you will have to revert back to stock to fix. For the latter, more research is required to figure out what's going on.

Use 3.3.1, it's what I have used to flash the T350 over 100 times during development.

I already sent nubianprince a PM, but this will take some time to figure out. I know he's busy and 3.3.1 works fine so there's no urgent need to fix this right away.
I was just literally going to post that the link is missing. :)
Also, it seems the link to the ROM doesn't work either which is weird.
 

retiredtab

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Nov 16, 2017
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For the one bug, 99% of you won't see it because only people developing the rom use it. TWRP allows you to do an adb shell for debugging/troubleshooting purposes, but it wasn't working on my tablet. It does, however, work on nubianprinces. We are discussing this in PM.

For the potentially serious second bug, this may be related to the version of bootloader that you currently have loaded similar to the BOE problem. Right now, I'm downloading the nougat stock rom that was originally on my tablet, but it's going to take 7 hours because it's limiting the speed to 15kbps (if it doesn't fail in between).

I should have results whether it's reproducible in the next few days. If it's not reproducible, then I may have had an "one off" event? Given the history of the SM-T350 and it's quirks with audio and BOE, I'm naturally suspicious. The BOE problem took months to figure out.
 
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retiredtab

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Nov 16, 2017
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DO NOT USE TWRP 3.5.0.10
Okay, I got my original nougat downloaded, flashed my tablet and went through what I recall are the exact same steps yesterday and I cannot recreate the problem. My rom boots correctly and adb works in TWRP with 3.5.0_10.

So I'm not 100% sure what went wrong yesterday. It could a have been a one-off bad flash. I probably have flashed 400+ times (100+ times per rom that I build) and maybe I was due for a bad flash? If it was a bad flash yesterday, there were no obvious error messages.

If you use any TWRP or rom, as always, make a backup of your files first.

BTW, this is NOT nubianprince's fault or a reflection of his code or testing. He tests all his builds just like I do, but we cannot replicate every possible scenario. So if I did have an "one-off" bad flash, it's not his fault.

In addition, I have run into TWRP bugs on other platforms that I have used in version 3.4.0.0 with adb not working.

Again, the only reason I flagged it with the "do not use twrp" was due to the SM-T350 finicky nature and it's bootloader with respect to BOE panels.
 
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retiredtab

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Nov 16, 2017
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For those who don't know TWRP 3.5.0 is the major version of the software. The _10 indicates that it's meant for devices that shipped with Android 10. See


TWRP 3.5.0_9 where _9 indicates it's for Android 9.0 or lower devices.

I suspect, but have no proof, that it's possible that 3.5.0_10 may have bug in it since it's the first release that supports A/B and system/vendor partitions. Maybe that initial flash wiped out one of my stock partitions by overwriting it with vendor partition or something and that's why reflashing complete stock fixed it since our roms don't flash all the partitions like stock does?

If/when nubianprince finds time to make another TWRP, it will likely be version 3.5.0_9 since the SM-T350 is deemed a "legacy device" in the article above. I think it's safer as well because our device isn't treble based and likely never will.
 
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bluenote73

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Jan 12, 2009
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For those who don't know TWRP 3.5.0 is the major version of the software. The _10 indicates that it's meant for devices that shipped with Android 10. See

[stuff about flashing down to the bare metal]
Hey RT,
Would you mind thumbnailing the steps to restore completely to stock including all partitions drivers etc, and then installing the ROM? I'm not a novice, but I am not extremely familiar with Samsung procedures. Including re-unlocking if that ends up being necessary?? [And it would be helpful to know which is the recommended stock version ..]
I want to do the same as you.
thx
 

retiredtab

Senior Member
Nov 16, 2017
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Hey RT,
Would you mind thumbnailing the steps to restore completely to stock including all partitions drivers etc, and then installing the ROM?
There's no magic above. You just use odin and flash stock rom. It's already scripted inside to flash over all the partitions that are included in the zip. For the 95% of the people reading this who run Windows this will work fine.

Since I'm in Canada, I picked from here the T350XXU1CQJ5 because that's the last stock that was on my tablet.


If you use linux, like me, you unzip the stock zip file and take a look at the stock partition names and match them up with the .pit file and manually type in the commands to do it. Something like


It's more work and potentially error prone especially if you mess up the secure and android bootloader you will get a bricked device, but you also learn more. This is how lpedia and discovered the root cause of the BOE problem at

 

retiredtab

Senior Member
Nov 16, 2017
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New version of TWRP 3.5.0 posted

Tested
  • Format data
  • Advanced wipe (data,cache,system,dalvik)
  • Install ROM
  • Backup restore
The new version that nubianprince posted is 3.5.0_9. I have tested the above, except for backup/restore, and verify it works. In addition, more importantly for people developing the rom, is that adb debugging works in TWRP mode.

@nubianprince, thanks for building 3.5.0_9 and quick turnaround.
 

retiredtab

Senior Member
Nov 16, 2017
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BOE panel fix

For people who get black or blank screens when trying to flash TWRP 3.3.1 or lineageos or crDroid SM-T350 roms, it's likely you have a BOE sourced panel. There is a fix as documented with the help of @lpedia. See pages 61 and 62 at

https://forum.xda-developers.com/galaxy-tab-a/development/recovery-t3426560/page61

https://forum.xda-developers.com/galaxy-tab-a/development/recovery-t3426560/page62

The above tells you why the problem exists and how flashing a 1MB aboot.mbn fixes it.
Feb 7, 2021 update. See post #671

 

bluenote73

Senior Member
Jan 12, 2009
696
154
63
There's no magic above. You just use odin and flash stock rom. It's already scripted inside to flash over all the partitions that are included in the zip. For the 95% of the people reading this who run Windows this will work fine.

Since I'm in Canada, I picked from here the T350XXU1CQJ5 because that's the last stock that was on my tablet.


If you use linux, like me, you unzip the stock zip file and take a look at the stock partition names and match them up with the .pit file and manually type in the commands to do it. Something like


It's more work and potentially error prone especially if you mess up the secure and android bootloader you will get a bricked device, but you also learn more. This is how lpedia and discovered the root cause of the BOE problem at

Once you're back to stock, I assume one needs to use Odin to put twrp back on right? And a special Odin compliant one? I'm going to do this today.