Hardware Support

Before installing AsteroidOS to your watch, make sure you are aware of the capabilities and limitations of AsteroidOS on the Asus Zenwatch 2. The following table should summarize the current support of this watch:

Preparation

Download AsteroidOS 1.0

Store the files in your "Downloads" folder so the later commands work

asteroid-image-wren.ext4 zImage-dtb-wren.fastboot

sudo apt install android-tools-adb android-tools-fastboot

Instructions

1. Unlock your bootloader

1. Open the settings app and go to the "About" page.
2. Tap the Build number 7 times until Developer options become enabled.

3. Go back to the settings menu and then to the "Developer options" page.
4. Enable ADB debugging.

adb reboot bootloader
fastboot oem unlock

2. Flash and boot AsteroidOS

1. Real installation
While your watch is in bootloader mode, flash the userdata and boot partitions using Linux:

fastboot flash userdata ~/Downloads/asteroid-image-wren.ext4
fastboot flash boot ~/Downloads/zImage-dtb-wren.fastboot
fastboot continue

or using Windows:

fastboot flash userdata %systemdrive%%homepath%\Downloads\asteroid-image-wren.ext4
fastboot flash boot %systemdrive%%homepath%\Downloads\zImage-dtb-wren.fastboot
fastboot continue

2. Temporary installation
Reboot to Wear OS, re-enable developer mode and ADB debugging.
Push AsteroidOS to the internal sdcard using Linux:

adb push -p ~/Downloads/asteroid-image-wren.ext4 /sdcard/asteroidos.ext4

or using Windows:

adb push -p %systemdrive%%homepath%\Downloads\asteroid-image-wren.ext4 /sdcard/asteroidos.ext4

Everytime you want to reboot AsteroidOS from Wear OS, run:

adb reboot bootloader

Then, if you are using Linux:

fastboot boot ~/Downloads/zImage-dtb-wren.fastboot

or on Windows:

fastboot boot %systemdrive%%homepath%\Downloads\zImage-dtb-wren.fastboot

3. Enjoy your new OS!

Troubleshooting & FAQ

• Fastboot displays "invalid sparse file format at header magic" message when start flashing
  This is not a fatal error but expected behaviour. Keep calm and wait for the ~5 minute flash process to finish. Fastboot simply informed you that the partitions it is now flashing where not downloaded in a "sparse" format.


• Flash fails with fastboot crashing or hanging at "invalid sparse file format at header magi" (missing the "c" in magic)
  This error often but strictly happend in our testing when using an old fastboot (& ADB below 1.0.39) on Windows systems. If you already had fastboot installed and skipped downloading our supplied zip file, please do so now.
  Either overwrite your current ADB & fastboot by extracting the zip into its folder. Or extract to a new folder instead (e.g. automatically to ...\adb_1_0_39+fastboot+ext2simg\) and change directory to that new folder.


• Flash fails or stops during the ~5 minutes process
  Smartwatches are prown to loose proper connection to their cradle over time due to sweat corroding the watch pins. Especially on dory (LG G Watch) this is a regular problem.
  Cleaning the pins with alcohol or even carefully sanding them (e.g. with a nailfile) can provide a reliable connection again.


• Asus Zenwatch 2 flashed successfully but does not boot
  As you may have missed, there are two versions of the Asus Zenwatch 2, codenamed Sparrow and Wren.
  Their images are not interchangeable. Make sure a second time you are using the right files.