Hello. I have orangepi zero 512mb + TFT Screen ili9341 fully working. Unfortunately, the screen size of 240x320 does not allow using Armbian 21.08.2 at this resolution. Is there a way to fix this at least a little bit? What Armbian code should I dig into?

Moved to P2P help.

Try change the disp_mode option in the file /boot/armbianEnv.txt to the resolution of the screen

 

If it doesn't work:

 - ls /sys/class/drm/   

 - cat /sys/class/drm/*/modes

 

The first one is to discovery the exact name of your display connection. In my case (orange pi pc connected via hdmi) it appears card0-HDMI-A-1, so the name of display connection is HDMI-A-1.

The second one is to check the available resolutions from your display device.

 

In addition to change disp_mode, add a line with extraargs to the file /boot/armbianEnv.txt.

Here is my example, adapt it to your case:
extraargs=video=HDMI-A-1:1920x1080@60
 

Note: the refresh rate does not appears in the command "cat /sys/class/drm/*/modes"