I am really sorry for the silly question. Even though I got TwisterOS running on my Radxa Zero, I am still trying to get either Ubuntu or Debian working on it.
Just download the img.xz file such as:
use Etcher to write to SD card and boot.
I’m having the same issues. I know how to use a RPi, but I cannot get these 2 Radxas to boot no matter what. Even tries the Boot From USB button. Looks like a 1.5 version and no eemc.
If your Radxa Zero doesn’t have eMMC, it’s simple, just download the mbr.img.xz file, write it to SD card, and insert the sdcard and power on.
Thank you, I will give it a try, but the TwisterOS works properly, I have even installed Robot Operating System (NOS) Noetic distro in it and it is working nice. Now the Radxa is used to program SMT32 boards and it is doing a great work. I love using the command line environment, even thought the TwisterOS is graceful. Visual Studio Code works very smoothly in it and it is a nice platform for development. I am planning though to use it as the brain of an autonomous drive robot, with gps, a camera with OpenCV and probably TensorFlow, audio for voice recognition, hmc5883l magnetic compass, a 2-D Xiaomi or Viomi lidar and other sensors.