• Introducing XDA Computing: Discussion zones for Hardware, Software, and more!    Check it out!
  • Fill out your device list and let everyone know which phones you have!    Edit Your Device Inventory

Teclast M40 Installing ROM from Windows

Search This thread

RudyGireyev

Member
Jan 12, 2021
12
1
Hello! Just received my first tablet, so am very new to all of this. :) Looking for guidance and direction. Glanced through the first page of Noob friendly thread and didn't see this addressed. So asking here.

Background: I ordered a Teclast M40 on Aliexpress and received it last week. I tried using Zoom on it and the person I was speaking to said that he could barely hear me. I then tried recording myself on the stock recording app app, and playing the file back indeed my voice was barely audible and somewhat muffled. I contacted the seller, and he sent me a Zip file asking me to reburn the stock ROM onto the Tablet thinking that this would solve the issue. I struggled with the software last week and refused to work. But this week, for whatever reason, everything worked and I was able to reflash the software. Obviously the issue was not resolved. Understanding that I am unlikely to get my money back, I now need to find a way to fix this myself, which is why I'm here.

My Questions
1. Since I have this software, do I still need to unlock the bootloader to flash a custom ROM?
2. Found a very helpful thread on Teclast M40 Here in it people talk about replacing the stock system with a gsi system. Which I never knew was an option until I came here. Since this appears less of an understaking, I'm hoping to try this first and see if it solves my microphone issue. The question is do I still need to unlock my device to install the GSI? Or can I just copy the GSI over the vbmeta.* files and burn it that way.

Just in case it is of any use here are some listings of directory entries from the Zip that I received from the Vendor I bought the Tablet from

Wiki:
 Directory of Z:\Zoot\Teclast

01/17/2021  10:49 PM    <DIR>          .
01/17/2021  10:49 PM    <DIR>          ..
01/13/2021  12:10 AM    <DIR>          Firmware
01/17/2021  10:49 PM                 0 rootFolder.txt
01/13/2021  12:11 AM    <DIR>          Upgrade Driver
01/14/2021  04:02 PM    <DIR>          Upgrade Tools
01/13/2021  12:11 AM           401,967 Upgrade tutorial.pdf

 Directory of Z:\Zoot\Teclast\Firmware

01/13/2021  12:10 AM    <DIR>          .
01/13/2021  12:10 AM    <DIR>          ..
01/13/2021  12:11 AM     3,342,253,832 Firmware.pac

 Directory of Z:\Zoot\Teclast\Upgrade Tools

01/17/2021  10:52 PM    <DIR>          .
01/17/2021  10:52 PM    <DIR>          ..
01/13/2021  12:11 AM               361 BinPack.ini
01/13/2021  12:11 AM            11,567 BMAConfig.xml
01/13/2021  12:11 AM           314,368 BMAFrame9.dll
01/13/2021  12:11 AM             1,214 BMError.ini
01/14/2021  10:09 PM             6,263 BMFileType.ini
01/13/2021  12:11 AM           290,816 BMPlatform9.dll
01/13/2021  12:11 AM             1,149 BMTimeout.ini
01/13/2021  12:11 AM             1,357 Channel.ini
01/13/2021  12:11 AM           252,928 Channel9.dll
01/13/2021  12:11 AM           266,240 CmdDloader.exe
01/13/2021  12:11 AM               228 CmdDloader.ini
01/13/2021  12:11 AM           803,727 Guide.chm
01/17/2021  09:54 AM    <DIR>          ImageFiles
01/13/2021  12:11 AM             2,413 MCPType.ini
01/13/2021  12:11 AM           139,264 PortHound.dll
01/13/2021  12:11 AM           196,608 ProcessFlow.dll
01/13/2021  12:11 AM               478 ProcessFlowSetting.ini
01/13/2021  12:11 AM           251,392 SecBinPack9.dll
01/13/2021  12:11 AM               244 SprdMes.ini
01/13/2021  12:11 AM         1,884,672 SprdMesApp.dll
01/13/2021  12:11 AM           120,056 udl_bkmark.bmp
01/13/2021  12:11 AM         1,763,328 UpgradeDownload.exe
01/17/2021  09:43 AM            14,385 UpgradeDownload.ini
01/17/2021  10:52 PM                 0 utFolder.txt

Running the UpgradeDownload.exe extract the image files from the Firmware directory and produces the following directory

Wiki:
 Directory of Z:\Zoot\Teclast\Upgrade Tools\ImageFiles\_DownloadFiles276766062

01/17/2021  10:54 PM    <DIR>          .
01/17/2021  10:54 PM    <DIR>          ..
01/17/2021  10:54 PM        36,700,160 boot.img
01/17/2021  10:54 PM            94,332 cache.img
01/17/2021  10:54 PM         8,388,608 dtbo.img
01/17/2021  10:54 PM           947,120 EXEC_KERNEL_IMAGE.bin
01/17/2021  10:53 PM            59,956 fdl1-sign.bin
01/17/2021  10:53 PM           632,612 fdl2-sign.bin
01/17/2021  10:54 PM           593,059 gnssmodem.bin
01/17/2021  10:54 PM           479,368 odmko.img
01/17/2021  10:54 PM         2,305,080 P20HD_EEA.bmp
01/17/2021  10:54 PM         2,305,080 P20HD_EEA.bmp(1)
01/17/2021  10:54 PM         2,097,152 persist.img
01/17/2021  10:54 PM            45,132 prodnv.img
01/17/2021  10:54 PM        41,943,040 recovery.img
01/17/2021  10:54 PM        26,214,400 SC9600_sharkl5pro_pubcp_customer_modem.dat
01/17/2021  10:54 PM         1,048,576 sharkl5pro_cm4.bin
01/17/2021  10:54 PM         6,291,456 sharkl5pro_pubcp_customer_AGCP_DSP.bin
01/17/2021  10:54 PM         1,048,576 sharkl5pro_pubcp_customer_CDMA_DSP.bin
01/17/2021  10:54 PM             2,264 sharkl5pro_pubcp_customer_deltanv.bin
01/17/2021  10:54 PM        10,485,760 sharkl5pro_pubcp_customer_DM_DSP.bin
01/17/2021  10:54 PM        20,971,520 sharkl5pro_pubcp_customer_LTEA_DSP.bin
01/17/2021  10:54 PM           765,396 sharkl5pro_pubcp_customer_nvitem.bin
01/17/2021  10:54 PM            53,796 sml-sign.bin
01/17/2021  10:54 PM        50,385,032 socko.img
01/17/2021  10:54 PM     3,124,144,944 super.img
01/17/2021  10:54 PM             1,940 teecfg-sign.bin
01/17/2021  10:54 PM         2,213,892 tos-sign.bin
01/17/2021  10:54 PM           632,612 u-boot-sign.bin
01/17/2021  10:54 PM            63,140 u-boot-spl-16k-sign.bin
01/17/2021  10:54 PM            32,545 ums512_1h10.xml
01/17/2021  10:54 PM           147,772 userdata.img
01/17/2021  10:54 PM         1,048,576 vbmeta-sign.img
01/17/2021  10:54 PM             4,096 vbmeta_system.img
01/17/2021  10:54 PM             4,096 vbmeta_vendor.img
 

jwoegerbauer

Senior Member
Jul 11, 2009
5,948
13
1,431
European Union
Flashing a Custom ROM requires a Custum Recovery gets flashed before, what as 1st thing of all things requires AVB gets disabled before - means toogle the related flag ( bits ) in the 3 vbmeta images , what is known as unlocking the bootloader.

The Teclast M40 is based on UNISOC T618 Aortex-A75 Core chipset. Hence its a good idea to use SPD Flash Tools , IMO, when it comes to operate on device's bootloader and/or Android OS.

Advice: Add "TECLAST M40" to front of this thread's title what will prevent visitors to unnecessarily open this thread for reading.
 
Last edited:
  • Like
Reactions: RudyGireyev

RudyGireyev

Member
Jan 12, 2021
12
1
Sorry my questions are going to be extremely Noob
Flashing a Custom ROM requires a Custum Recovery gets flashed before,
This device is brand new and I have nothing on it that I want/need to save. Do I still need the Recovery?

what as 1st thing of all things requires AVB gets disabled before - means toogle the related flag ( bits ) in the 3 vbmeta images , what is known as unlocking the bootloader.
Is there a link that someone as new as me can check out and see a little bit more info about this?
The Teclast M40 is based on UNISOC T618 Aortex-A75 Core chipset. Hence its a good idea to use SPD Flash Tools , IMO, when it comes to operate on device's bootloader and/or Android OS.
So it siunds like you are saying don't use the software that I already have, that the Vendor sent me
Advice: Add "TECLAST M40" to front of this thread's title what will prevent visitors to unnecessarily open this thread for reading.
Done! Thank you.
 

jwoegerbauer

Senior Member
Jul 11, 2009
5,948
13
1,431
European Union
  • The Stock Recovery, that comes by default with all Android devices, only allows to re-flash tablet's Stock ROM - means a ROM signed by OEM/carrier and compiled for that tablet, whereas a Custom Recovery skips the related signature-verification process hence you can flash any matching ROM onto your tablet.
  • Android 7.0 started strictly enforcing Verified Boot ( AVB ) to prevent compromised devices from booting.
    With regards to unlocking tablet's bootloader - i.e. disable AVB: Typically people by means of SPD Research Tool extract existing vbmeta-sign.img, then pass this extracted file to Fastboot - the default tool to operate on Android devic's bootloader - what rewrites it at its own when you run
    Code:
    fastboot devices
    fastboot --disable-verity --disable-verification flash vbmeta-sign vbmeta-sign.img
    fastboot reboot
  • It's on you to use the software provided by vendor. It was only a hint to use SPD Flash Tools instead. :)

FYI:
I don't own that tablet, hence I can't guide further. Thanks for your understanding.
 
Last edited:
  • Like
Reactions: RudyGireyev

RudyGireyev

Member
Jan 12, 2021
12
1
What would be a good place to see all of the steps involved in rooting? At the moment I see 2 rooting options. (There may of course be more)
1. Installing an OS like Lineage and others (I'm not sure what that does, I assume it simply replaces the entire ROM.
2. Modifying/Replacing the GSI which (does something that you described and I didn't quite understand :D :)) to the vbmeta files.
 

steve.l

Member
Nov 16, 2010
14
2
Hi,
My Teclast M40 has the same problem as yours regarding volume of recorded sound from the built in microphone. Based on the icons painted on the back of the tablet it appears the microphone is located between the two speakers. However, you will notice there is no hole cut in the case where the microphone should be. I looked all over the tablet for another microphone hole and the only other holes are for the reset button and speakers. So I think this is a design defect that cannot be corrected in software. The only option you have is to open the device, locate the microphone and cut a hole in the case to allow sound in, OR use a headset. Hope this helps.

Steve
 

doguitto

Member
Feb 26, 2010
5
0
Hi,
My Teclast M40 has the same problem as yours regarding volume of recorded sound from the built in microphone. Based on the icons painted on the back of the tablet it appears the microphone is located between the two speakers. However, you will notice there is no hole cut in the case where the microphone should be. I looked all over the tablet for another microphone hole and the only other holes are for the reset button and speakers. So I think this is a design defect that cannot be corrected in software. The only option you have is to open the device, locate the microphone and cut a hole in the case to allow sound in, OR use a headset. Hope this helps.

Steve
Hi,
Did you manage to open the tablet and cut a hole? Does the problem got solved?

Regards
 

Top Liked Posts

  • There are no posts matching your filters.
  • 1
    Flashing a Custom ROM requires a Custum Recovery gets flashed before, what as 1st thing of all things requires AVB gets disabled before - means toogle the related flag ( bits ) in the 3 vbmeta images , what is known as unlocking the bootloader.

    The Teclast M40 is based on UNISOC T618 Aortex-A75 Core chipset. Hence its a good idea to use SPD Flash Tools , IMO, when it comes to operate on device's bootloader and/or Android OS.

    Advice: Add "TECLAST M40" to front of this thread's title what will prevent visitors to unnecessarily open this thread for reading.
    1
    • The Stock Recovery, that comes by default with all Android devices, only allows to re-flash tablet's Stock ROM - means a ROM signed by OEM/carrier and compiled for that tablet, whereas a Custom Recovery skips the related signature-verification process hence you can flash any matching ROM onto your tablet.
    • Android 7.0 started strictly enforcing Verified Boot ( AVB ) to prevent compromised devices from booting.
      With regards to unlocking tablet's bootloader - i.e. disable AVB: Typically people by means of SPD Research Tool extract existing vbmeta-sign.img, then pass this extracted file to Fastboot - the default tool to operate on Android devic's bootloader - what rewrites it at its own when you run
      Code:
      fastboot devices
      fastboot --disable-verity --disable-verification flash vbmeta-sign vbmeta-sign.img
      fastboot reboot
    • It's on you to use the software provided by vendor. It was only a hint to use SPD Flash Tools instead. :)

    FYI:
    I don't own that tablet, hence I can't guide further. Thanks for your understanding.