Boot Images from External Media

There are many images that are designed to run from an SD Card or Thumbdrive (U-Disk). For example, CoreELEC, LibreELEC, Armbian images and Khadas SD images. This tutorial is about how to boot these images.

In order to boot images from external media you must make sure:

  • Android is running on the eMMC
  • Activate the Multi-Boot

For different images you may need different Android versions.

  • LibreELEC / Ubuntu with Linux 3.14: You need Android M or the latest Android N (V180207 or later) running on the eMMC.
  • Ubuntu with Linux 4.9: You need Android O running on the eMMC.

1. Write image to SD-Card or Thumbdrive (U-Disk)

  • Use dd on the Ubuntu command line

    $ sudo dd if=/path/to/image of=/dev/sdX bs=8M
  • Use Win32DiskImager on Windows. Please refer to Install LibreELEC Via Windows PC.

2. Prepare DTB

You will have to choose different DTB for VIM1 and VIM2.

  • VIM1: Copy kvim.dtb, kvim_linux.dtb or meson-gxl-s905x-khadas-vim.dtb to /boot and rename it to dtb.img.
  • VIM2: Copy kvim2.dtb, kvim2_linux.dtb or meson-gxm-khadas-vim2.dtb to /boot and rename it to dtb.img.

3. Activate The Multi-Boot

2 ways to activate Multi-Boot:
1). Via Keys mode (Side-Buttons).
2). Activate Multi-Boot via Android.

  • Enter Settings>About Device->System->Updates.
  • Click select and choose aml_autosript.zip.
  • Click update, then the system will reboot and boot from the external media image.
    Note: Don’t use your PC as the USB-Host to supply the electrical power, lest it will fail to activate Multi-Boot!

NOTICE

  • Android N has a permission issue. You cannot use it to boot from your external media image without damaging your SD card.

  • Android O also has a permission issue. If you want to boot Ubuntu with Linux 4.9 please refer to this guide.