Hi manuelbrunopt,
This is how to enter QDLoader or Download mode for Qualcomm devices.
- download and install qualcomm hs usb QDLoader driver here.
Choose 32bit or 64bit driver for Windows 32bit or 64bit - On Hipad Pro, open Settings > Developer Settings > USB Debugging
- Connect Hipad Pro to PC via Type C cable. (Windows required)
- Open adb fastboot plaform tool > Enter this command
adb devices
Hipad Pro will ask permission to allow USB Debugging mode > choose Allow - Enter this command
adb reboot edl
Hipad Pro will reboot to blank screen which is Download mode or QDLoader mode - Open Control Panel > Device Manager > Port (Com & LPT)
You will see Qualcomm HS-USB QDLoader 9008 (ComXX) Mine is Com10
- Open QFIL
You will see the connection shows up with com port which has to be the same as shown in Device Manager
Both screenshots are from my PC. So I can confirm these steps will make Hipad Pro enter QDLoader mode.
After this you can follow the steps for flashing Stock firmware via QFIL (Flash Tools) in the manual. At this point your Hipad Pro will be in QDLoader mode with blank screen. If you want to get out of this mode, hold volume down + power until the screen boot Chuwi logo. This will boot up and enter system.
I did not create this Stock firmware, just shared from Anathema from this post.