[ed_ray]

My android device is a TecLast M20_4G tablet, manufacturer Mediatek with 4g ram, 64g storage(ROM), chipset MT6797. This is an android 8.0 OS device. The build number is: V1.01_20181009, kernel version is 3.18.60, zengqb@jty #4, wed Oct 10 10:45:48 CST 2018.

Root goal: 
My goal was to root the device using Magisk Manager & my stock boot image using the steps stipulated in “How to use Magisk Manager & boot.img to root Android” since I was NOT able to locate any custom recovery for this device which would have been easier to root with (if any folks reading this post know of any existing custom recovery for this device, please let me know).
 
As recommended by the forum folks, I backed up my entire tablet image first via the steps specified below:
 
Complete image backup first:
First as recommended, I backed up my entire android device image (58.2 g on a 64 g device) using the steps “How to use Miracle Box to backup Mediatek (MTK) firmware”. I used Miracle Box v2.58 + Loader.exe (no hardware box/dongle required).
 
“Mediatek VCOM drivers” not needed?
In order to connect per USB, I used a MediaTek android composite ADB interface driver. I connected successfully without any problem and my device was immediately recognized Note: Since I was able to connect successfully with my manufacturer driver, I did not use/install the “Mediatek VCOM drivers” to avoid any POTENTIAL driver clashes. Please let me know If I was OBLIGATED to install the VCOM drivers regardless of a SUCCESSFUL connection using my original MediaTek driver.
 
I followed the steps and did NOT use a scatter file. The backup was successful, and I ended up with a
58.2g bin file.
 
Stock boot image backup:
Since I did not see any option to back up only the stock boot image without a scatter file,  I used the  scatter file method.  I went ahead and backed up the “BOOT” option of the scatter file selection and as recommended by your forum notes, I also selected the recommended “Preloader” option. All other options were deselected.  This backup was successful producing the text scatter file and the boot.bin and preloader.bin files.
 
I then renamed “boot.bin” to “boot.img” and copied it into the downloads folder of my tablet device where I used the “Magisk Manager“ to patch the boot.img file. It seemed to work yielding a “patched boot.img” file.
 
[[The part that is NOT clear and not concisely explained in the “How to use Magisk Manager & boot.img to root Android” steps.]]
 
When the “patched boot.img” file is brought to the PC side to use the miracle box software to flash the “patched boot.img” file to root the tablet, does the file have to be renamed to “boot.bin” overwriting the original “boot.bin” the scatter file was originally referencing inside its text contents?
 
I don’t see any other way to do this. If there is, please let me know since the instructions say nothing regarding what to do at this step in the process.
 
If this is correct, then at this point I would select the scatter file and click the start button. I am reluctant to do this until someone tells me this is the correct thing to do at this point of the flash process. PLEASE ADVISE ME at this step before I proceed.
 
Note: As previously specified, I never installed the ““Mediatek VCOM drivers” to avoid driver clashes because my original MediaTek manufacturer “android composite ADB interface driver” worked and connected without any problems throughout all the different Miracle Box process steps.
 
Thanks in advance to all respondents.

[X3non]

...
[[The part that is NOT clear and not concisely explained in the “How to use Magisk Manager & boot.img to root Android” steps.]]
 
When the “patched boot.img” file is brought to the PC side to use the miracle box software to flash the “patched boot.img” file to root the tablet, does the file have to be renamed to “boot.bin” overwriting the original “boot.bin” the scatter file was originally referencing inside its text contents?
 
I don’t see any other way to do this. If there is, please let me know since the instructions say nothing regarding what to do at this step in the process.
 
If this is correct, then at this point I would select the scatter file and click the start button. I am reluctant to do this until someone tells me this is the correct thing to do at this point of the flash process. PLEASE ADVISE ME at this step before I proceed.
 
Note: As previously specified, I never installed the ““Mediatek VCOM drivers” to avoid driver clashes because my original MediaTek manufacturer “android composite ADB interface driver” worked and connected without any problems throughout all the different Miracle Box process steps.
 
Thanks in advance to all respondents.

to flash patched_boot.img using miracle box, you need to rename it back to boot.bin
copy boot.bin to the same folder location as preloader and scatter file then flash preloader and boot. see https://www.hovatek.com/forum/thread-14106.html

[hovatek]

It would have been better to do a full backup instead of just preloader & boot. Never know when it'll come in handy.
In addition to what  @x3non said, ensure to keep your original boot.bin. You're just to rename patched_boot.img to boot.bin > create a folder > copy the patched boot.bin+ scatter file + preloader into the folder > Flash

[[The part that is NOT clear and not concisely explained in the “How to use Magisk Manager & boot.img to root Android” steps.]]

The tutorial couldn't possibly explain all technique for flashing boot because it depends on your situation. We just used fastboot method as example since it cuts across all chipsets

[ed_ray]

[X3non]

...

flashing boot or another other partition without preloader will result to an error when using miracle box
i made mentioned to "flash both preloader and boot"
so when the box to select which partition(s) you intend to flash pops up, tick the checkbox beside both preloader and boot then proceed to flash


PS: for custom recovery, you can try twrp @ https://www.hovatek.com/forum/thread-21839.html  or philz @ https://www.hovatek.com/forum/thread-21495.html

[ed_ray]

Thanks for the response. The procedure example only shows the boot being ticked and no preloader even on screen to be ticked, but since you recommended to tick both the preloader and boot parts I will do just that.

I don't think I can use either the TWRP or any other custom recovery because based on their web info, no such recoveries were ever made for my particular device. Their lead person clearly specified that any custom recovery is device dependent and one such recovery would have to be made just for one's particular device.

This is why I asked if I could make a copy of my own stock recovery and if there were any tools miraclebox or anything else that would let me modify the recovery image something like what Magisk manager does when patching the stock boot image to end up with a custom recovery for my own device.  

Still have not received an answer for the original query part below which stated:

"By the way just for completeness, since my manufacturer "android composite ADB interface driver has been used so far without any connections issues when doing a previous successful complete image and the individual boot image backups, is it OK that I did not install and use the "Mediatek VCOM drivers”.  I just want to make sure I won't have flashing problems from that point forward." 

Many thanks for your recommendations.
Ed_Ray

flashing boot or another other partition without preloader will result to an error when using miracle box
i made mentioned to "flash both preloader and boot"
so when the box to select which partition(s) you intend to flash pops up, tick the checkbox beside both preloader and boot then proceed to flash


PS: for custom recovery, you can try twrp @ https://www.hovatek.com/forum/thread-21839.html  or philz @ https://www.hovatek.com/forum/thread-21495.html

[hovatek]

Thanks for the response. The procedure example only shows the boot being ticked and no preloader even on screen to be ticked, but since you recommended to tick both the preloader and boot parts I will do just that.

I don't think I can use either the TWRP or any other custom recovery because based on their web info, no such recoveries were ever made for my particular device. Their lead person clearly specified that any custom recovery is device dependent and one such recovery would have to be made just for one's particular device.

This is why I asked if I could make a copy of my own stock recovery and if there were any tools miraclebox or anything else that would let me modify the recovery image something like what Magisk manager does when patching the stock boot image to end up with a custom recovery for my own device.  

Still have not received an answer for the original query part below which stated:

"By the way just for completeness, since my manufacturer "android composite ADB interface driver has been used so far without any connections issues when doing a previous successful complete image and the individual boot image backups, is it OK that I did not install and use the "Mediatek VCOM drivers”.  I just want to make sure I won't have flashing problems from that point forward." 

Many thanks for your recommendations.
Ed_Ray

Speaking of drivers, I think you're good so no need to re-install.
Just so we're straight, the scatter file, preloader & boot.bin (patched) should be in the same folder then you tick both boot & preloader when flashing with miracle box

Speaking of custom recovery, @x3non already gave you links to tool we created for porting custom recovery. You just feed our tool your stock recovery, select Android version and it'll do the rest.
"PS: for custom recovery, you can try twrp @ https://www.hovatek.com/forum/thread-21839.html  or philz @ https://www.hovatek.com/forum/thread-21495.html "

Speaking of your backup, I strongly recommend a full scatter dump over a single .bin dump