Watches ⟩ Casio WSD-F10/F20

Hardware Support


Please make sure to test all hardware functions of your watch in your current operating system to rule out hardware defects before installing AsteroidOS. You can report any hardware support issue here. Use the label ayu/koi for issues specific to your watch.

The following list shows the state of the features of the koi version of this watch.

goodDisplay
goodTouch
goodBluetooth
goodHaptics
goodTilt-to-Wake
goodAlways-on-Display
partialDual-Display
unknownMicrophone
goodCompass
goodUSB
goodWLAN
badGPS
Model NumberModel NameCodename
WSD-F10Casio Smart Outdoor Watchkoi
WSD-F20Casio Pro Trek Smartayu

WARNING: Bricking issues!

These watches are known to brick themselves in various ways. Most bricks are recoverable, but occasionally the watch will seemingly corrupt its bootloader partition, which will cause it to get stuck in WearOS and bootloop. Proceed with extreme caution and consult our matrix chat before installing.

Model number and variants

The "Casio Smart Outdoor Watch WSD-F10" koi and "Casio Pro Trek Smart WSD-F20" ayushare a platform. The only difference is the inclusion of GPS and a modified casing design in the ayu model. Generally, both watches are referred to as koi.

AsteroidOS has only been tested on ayu, but it should work on koi. The USB access procedure for the WSD-F10 koi is unknown. If you have a WSD-F10 and want to help test, please get in touch with us on #Asteroid:matrix.org.

The Casio WSD-F21HR and WSD-F30 are completely separate watches and not compatible with koi. Work is currently in progress on the WSD-F21HR.

USB connection

Both models need a custom adapter cable to connect to the USB pads.

On ayu the USB pads are hidden under the Casio logo plate. Accessing those pads does not affect your watch's water resistance.

The front bezel can be removed by unscrewing the four screws on the front of the watch and unclipping the faceplate. The Casio logo plate should then come free.

Then you can then use pogo pins to connect a USB cable to the watch. The left pad is D- (white) and the right pad is D+ (green). Ensure that the magnetic charger is also connected to the watch while accessing USB, as it is needed for the signal ground. The charger should be connected to the same computer as your USB data cable.

Do not, under any circumstances, solder to the pads. This can melt the plastic casing of the watch and cause all sorts of other damage.

There is currently no 3D printable dock for this watch, but feel free to design one and share it with the community!

Prepare installation

Inform yourself

See the watch wiki page for up-to-date information about this watch.

Prerequisites

Your Watch is running


Show instructions for


Downloads

Download AsteroidOS for koi

Store the files in your "Downloads" folder so the later commands work
asteroid-image-koi.rootfs.ext4 zImage-dtb-koi.fastboot


Install ADB & Fastboot


Debian / Ubuntu
sudo apt install android-tools-adb 
android-tools-fastboot
Fedora / CentOS
sudo dnf install android-tools
OpenSUSE
sudo zypper install android-tools
Arch and derivatives
sudo pacman -Sy android-tools
Install the Google USB driver

Get the Google USB Driver ZIP

Download this zip file containing ADB & Fastboot from Android SDK

adb-1_0_39+fastboot+ext2simg.zip

Extract the content to a folder of your liking.
Navigate to that folder using the Windows commandline (cmd.exe).


Instructions

1. Unlock your bootloader

Note

Unlocking the bootloader may void your warranty.
The unlock process will trigger a factory reset of Wear OS. Backup any data you do not want to loose.

Warning

DO NOT relock the bootloader while having AsteroidOS installed. This puts the device into a non-recoverable state.
Installing and booting AsteroidOS requires an unlocked bootloader.
Accessing the fastboot bootloader menu on your watch can be achieved either by using ADB in Wear OS or by manually stopping the boot process at the fastboot screen.
If you are familiar with the manual method to access the bootloader menu on your watch, you can skip to step 1.3. Those methods are explained on the useful commands page. To boot into fastboot menu from ADB within WearOS, follow steps 1.1 to 1.2.

1.1 Enable ADB on your watch

1. Open the settings app
2. Open the System page
3. Open the About page
4. Tap the Build number 7 times to reveal Developer options
5. Open the Settings app again
6. Open the Developer options page
7. Enable ADB debugging

1.2 Reboot to fastboot bootloader mode

Enter the following ADB command in a terminal with your watch connected to USB.
adb reboot bootloader

1.3 Use fastboot to unlock the bootloader

With your watch now in fastboot mode, enter this command in a terminal to start the unlock procedure.
fastboot oem unlock

1.4 Follow the instructions on your watch's screen

Please note again, this may void your warranty and will wipe your userdata.

1. Reboot into fastboot bootloader menu

If your watch can be booted into AsteroidOS, all of the below described methods work to access the fastboot menu on your watch.
In case AsteroidOS can not be booted successfully, use the manual method.

1.a Manual method

Long press the power button for up to 10 seconds until the watch reboots. Then quickly perform a key combination or sequence right when the watch powers on again, to stop the boot process at the fastboot screen. The specific key combination for your watch is explained on the useful commands page.

1.b Using ADB

Set ADB Mode in the USB page of the AsteroidOS Settings app.
Enter the following ADB command in a terminal with your watch connected to USB.
adb reboot bootloader

1.c Using SSH

Set SSH Mode in the USB page of the AsteroidOS Settings app.
Enter the following SSH command in a terminal with your watch connected to USB.
ssh ceres@192.168.2.15 "reboot bootloader"


2. Install and boot AsteroidOS

2.1 Choose your installation type

Try AsteroidOS as a dual-boot by sideloading the AsteroidOS system image and boot it only temporarily.
This a good way to try if AsteroidOS meets your requirements. Or in case you don't plan to use AsteroidOS daily and intend to not permanently replace your previous OS.
The only differences compared to a real installation are very limited disk space and the necessity to manually boot AsteroidOS on every restart.

Replace WearOS definitively by flashing the system and boot image.
The real installation provides the best experience, but it is advised to make a backup of your previous OS first.
We highly recommend to first test if AsteroidOS meets the requirements of your usecase by performing the non invasive temporary installation before permanently replacing your previous OS.

2.2 Real installation using Linux

Reboot to Wear OS, re-enable Developer options and ADB debugging like shown in steps 1.1.1 - 1.1.7.
Note, you can access the Wear OS settings app via long press of the power button already while the initial pairing screen is shown.

Push AsteroidOS to the internal sdcard:
adb push -p ~/Downloads/asteroid-image-koi.rootfs.ext4 /sdcard/asteroidos.ext4
Boot your watch into fastboot bootloader mode, then flash the boot partition:
fastboot flash boot ~/Downloads/zImage-dtb-koi.fastboot
Then continue the boot process:
fastboot continue

2.2 Real installation using Windows

Reboot to Wear OS, re-enable Developer options and ADB debugging like shown in steps 1.1.1 - 1.1.7.
Note, you can access the Wear OS settings app via long press of the power button already while the initial pairing screen is shown.

Push AsteroidOS to the internal sdcard:
adb push -p %systemdrive%%homepath%\Downloads\asteroid-image-koi.rootfs.ext4 /sdcard/asteroidos.ext4
Boot your watch into fastboot bootloader mode, then flash the boot partition:
fastboot flash boot %systemdrive%%homepath%\Downloads\zImage-dtb-koi.fastboot
Then continue the boot process:
fastboot continue

2.2 Temporary installation using Linux

Reboot to Wear OS, re-enable Developer options and ADB debugging like shown in steps 1.1.1 - 1.1.7.
Note, you can access the Wear OS settings app via long press of the power button already while the initial pairing screen is shown.

Push AsteroidOS to the internal sdcard:
adb push -p ~/Downloads/asteroid-image-koi.rootfs.ext4 /sdcard/asteroidos.ext4
Everytime you want to boot into AsteroidOS, first boot your watch into fastboot bootloader mode.
Flash the boot image to the recovery partition:
fastboot flash recovery ~/Downloads/zImage-dtb-koi.fastboot
Then boot to recovery:
  1. Hold the top key while powering up
  2. Push it again to select "recovery"
  3. Press the power key to boot to recovery

2.2 Temporary installation using Windows

Reboot to Wear OS, re-enable Developer options and ADB debugging like shown in steps 1.1.1 - 1.1.7.
Note, you can access the Wear OS settings app via long press of the power button already while the initial pairing screen is shown.

Push AsteroidOS to the internal sdcard:
adb push -p %systemdrive%%homepath%\Downloads\asteroid-image-koi.rootfs.ext4 /sdcard/asteroidos.ext4
Everytime you want to boot into AsteroidOS, first boot your watch into fastboot bootloader mode.
Flash the boot image to the recovery partition:
fastboot flash recovery %systemdrive%%homepath%\Downloads\zImage-dtb-koi.fastboot
Then boot to recovery:

3. Enjoy your new OS!

See the wiki for synchronization clients, SSH access, watchface and package installation, backup guide and much more!



Boot problems

Bootloop of any kind or stuck boot process

Don't panic. None of the commands we advised you to use can damage or brick your watch permanently.
You can always go back to the fastboot bootloader menu, by using the manual finger combos for your watch.

Boot gets stuck even after repeated reflash

Congratulations, you might have found a new issue for us to solve. While this should not happen with stable builds, the nightlies are advancing quickly, and are not tested on all watches. You are likely using a nightly build, as the installation pages currently link to those. You can try again and install a stable build when available.
To help us solve the problem, you could try to collect logs. It is possible that the watch does not show a UI but is already accessible using ssh ceres@192.168.2.15 or adb shell in the state the boot process stops. In case SSH connection works, try the following commands to write logs to local .txt files. or, if your watch presents an ADB interface, use the following commands: In case no connection is available, it is still interesting to see if the watch leaves any traces in your local dmesg. Try to spot USB related messages in sudo dmesg -w while the watch is connected and booting. Record the log using the sudo dmesg > dmesg-local.txt command.
You can share those logs in a new Github issue tagged with the watch codename. For support chat, you are invited to join our Matrix channel.

Watch only boots when powered via USB, but shuts off when booted while worn

This is a clear sign of a worn battery that will soon fail. Maybe you should replace it.
The boot process of AsteroidOS uses all cores of a watch to ensure a fast startup. This leads to power spikes during the boot process, which can completely shut down watches with worn out batteries. It has been observed that WearOS can still boot on watches with worn out batteries, but AsteroidOS cannot, depending on the progress of battery wear. However, AsteroidOS can usually still provide a useful 10-20 hours of uptime when the watch is worn once booted while powered up.
Batteries are relatively easy to replace on watches with screwed down backs. Glued back plates usually require creative solutions involving hair driers.

Watch successfully boots into the AsteroidOS user interface, but immediately reboots

This is a known behavior when the battery charge is very low. The watch usually recovers from this condition by simply boot cycling for some time. All watches also charge in fastboot or recovery mode. Letting the watch dwell on the fastboot or recovery menu screen for some time should fix the problem even faster.

Flashing problems

Watch is not detected and all fastboot commands fail

ADB connection works, but fastboot does not?

The fastboot oem unlock command not working even though the watch could be booted into fastboot mode using adb reboot bootloader is a known issue on windows systems. It is caused by using a watch manufacturer USB driver with missing fastboot support. Try removing that one and install the offical Google USB driver we linked above in the install section.

Fastboot command crashes or hangs at "invalid sparse file format at header magi" (explicitly missing the "c" in magic)

This error occurs when using deprecated fastboot and ADB versions on Windows systems. If you already had adb.exe and fastboot.exe installed and skipped downloading our supplied ZIP file, please install and try those commands instead. Another reliable source for updated windows ADB and fastboot versions is the official Google platform tools ZIP file.

Fastboot command stops with error during the ~5 minute flashing process

Smartwatches are prone to lose a proper connection to their cradle over time due to sweat corroding the watch pins.
Clean the pins and pads with isopropyl alcohol and repeat the flashing process.
Try to ensure a stable USB connection by putting the watch and your computer on the same flat surface. Try to not move the cable connecting your computer and the watch during the whole flashing process. In case of worn or corroded contacts and pogo-pins that lost their springiness, it might be useful to attach the watch to its cradle or charging cable using duct tape or rubber bands.

Fastboot command displays "invalid sparse file format at header magic" when starting to flash the device

This is not a fatal error and can safely be ignored. Fastboot expects images to be in sparse format. When a raw image is supplied like in case of most of the AsteroidOS watches, fastboot converts it to sparse and shows above message.