Addendum to install on the Redmi Note 9pro
Installation of PitchBlackRecovery
Meanwhile, you can leave the PitchBlackRecovery installed, you can then still install or update the system.
The official recovery for the Note 9pro can be downloaded here: https://pitchblackrecovery.com/joyeuse/
After downloading the packed file, go to the folder “TWRP”, there is a “recovery.img”. This image file I copy into the folder “platform-tools”, there I do not have to enter so much in the console, that’s all.
It is installed like this:
Boot the phone in bootloader mode, a picture appears and below it says “FASTBOOT”.
On the PC enter via the console
fastboot devices
Now the serial number should be displayed and a bit further to the right it says “fastboot”.
This is just to check if the phone was also recognized!!!
Now you can enter:
fastboot flash recovery recovery.img
After that you can enter
fastboot reboot recovery
Now PitchBlackRecovery starts, if the phone is encrypted, you must enter the PIN, then you come to the main menu.
Install or update the system
If you want to reinstall the system or install a system update, you have to enter the bootloader (fastboot) mode again. If one is there, one enters:
fastboot reboot fastboot
So, now for the difference as in the original instructions at the top, no fastbootD mode appears, but the phone starts into the fastboot mode of the PitchBlackRecovery, this takes a few seconds longer as with the original recovery.
I also copied the system image to the “platform-tools” folder, saves unnecessary entries in the console.
The image is installed with:
fastboot flash system GSI.img
When all this is installed, you can simply go to “reboot” at the bottom right of the phone.
Procedure after installation of an update - In the next screen you can select “System”, after that a new screen opens, there you can move the “slider” from left to right. The phone now reboots into the system, the update is installed.
System has been reinstalled - In the next screen you select “Recovery”, in the next screen you simply move the “slider” from left to right. Now the phone reboots into PitchBlackRecovery. After entering a possible PIN to unlock, you are in the main menu. There you select “Erase”, in the next screen you go to “Format data”, enter “yes” and follow the instructions on the screen to format the phone, more precisely the data. This should do the same as if you go to “Erase data” in the original recovery. I have not tested this yet.
Of course you can also install the system update without the PitchBlackRecovery, just like in the first tutorial above. Only with the difference that you do NOT delete the data at point 7, but simply reboot the system.
The images can still be found at this address: https://android.l1nux.org/index.php/s/tNyG9ZcrjGBPrdH