ZSWatch
Table of content
- ZSWatch
About
Smartwatch built from scratch, both hardware and software. Built on the Zephyr™ Project RTOS, hence the name ZSWatch - Zephyr Smartwatch.
https://github.com/jakkra/ZSWatch/assets/4318648/ec1a94fd-a682-4559-9e68-f3e5bfcbe682
Features
Hardware
- nRF5340 BLE chip (u-blox NORA-B10 module)
- 128 MHz Dual core
- 512 KB RAM
- 1 MB Flash
- 30 MHz SPI for display
- 240x240 round display with touch screen
- IMU Bosch BMI270, with this one it's possible to do many fancy things such as navigation using gestures and the typical smartwatch wakeup by moving the arm so the display is viewable
- Bosch BME688 Environmental sensor with AI
- Bosch BMP581 High performance pressure sensor accuracy in units of ~20cm's
- ST LIS2MDLTR Magnetometer
- Macronix MX25U51245GZ4I00 64 MB external flash
- Broadcom APDS-9306-065 Light Sensor for automatic brightness control
- Micro Crystal RV-8263-C8 RTC for time keeping and alarm functions
- Knowles SPK0641HT4H-1 I2S microphone for audio recording
- Nordic nPM1300 PMIC for power and system management
- Texas Instruments TS3USB221A USB / SWD switch to provide a USB or SWD interface on the dock connector
- Option to not mount sensors to save BOM cost
PCB
A 4-layer board that measures 38mm in diameter is designed in KiCad. More info here.
Software
- Bluetooth LE communications with GadgetBridge Android app.
- Also support Bluetooth Direction Finding so the watch can act as a tag and is trackable using any u-blox AoA antenna board
- Multiple Watchfaces showing:
- Standard stuff such as time, date, battery
- Weather
- Step count
- Number of unread notifications
- Environmental data
- ...
- Pop-up notifications
- Application picker and app concept
- Step counting
- Gestures
- And much more ...
Watchfaces
The watch supports different watchfaces which can be changed dynamically. The watch also supports ESP32 watchfaces from Felix Biego. Please checkout this fork for more informations.
Smartphone communication
Pairing
- In the watch go to
Settings->Bluetooth->Enable pairing - Now go reconnect to the watch from the Gadgetbridge app
- You should now be paired
Android phone communication
Fortunately, there is a great Android app called GadgetBridge that handles everything needed on the phone side, such as notifications management, music control and so much more. The ZSWatch right now pretends to be one of the supported Smart Watches in Gadgetbridge, following the same API as it does. In the future there may be a point in adding native support, we'll see.
iOS device communication
Apple exposes Apple Notification Center Service GATT server which handles notifications management on the phone side, music control is done in the same fashion using Apple Media Service... The ZSWatch communicates straight to the iOS with no extra Apps.
Enclosure/Casing
3D printed casing with 3D printed buttons, option CNC:able casing in metal.
Upcomming features
There are almost endless possibilities for features that could be implemented, see here for full progress and in GitHub issues.
Charger/Dock
Option with and without onboard SEGGER J-Link OB debugger. As the debugger requires a license, this will only be available as part of a kit.
See more at here.
Demos
Building or getting one
- Head over to the hardware repos for the PCB and the Dock for information about ordering the PCBs and assembly from PCBWay
- Go to the Wiki for information how to print parts and assemble ZSWatch
Some things are still in progress:
- Building instructions in Wiki
- Dock casing
I'll also build a few initial kits (assembled) for those who don't want or can build ZSWatch themselves. In addition to the assembled ZSWatch and dock you will get the following compared to if you build it yourself:
- A magnetic dock connector and cable. I got custom-ordered cables to fit the needs of ZSWatch
- Dock with onboard SEGGER J-Link OB debugger, which means you won't need an external debugger for ZSWatch development and flashing
- Possibly CNC:ed casing in Stainless steel
If you are interested in a kit or want to get notified when the missing parts above are resolved, fill in your mail here (Google form) and I'll send a reminder when it's ready.
Or if you want to get notified for releases and when the missing parts are finished simply press the Watch button (next to Fork and Star) -> Custom -> Releases and you will see in your feed when it's officially released.
Environment, Compiling and running the code
See Wiki page about Start Developing.
Writing apps for the Application Manager
See Wiki page about apps.
Licence GPL-3.0
The main difference from MIT is now that if anyone wants to build something more with this, then they need to also open source their changes back to the project, which I think this is fair. This is so everyone can benefit from those improvements. If you think this is wrong free to contact me and I'm open to change the LICENCE.
Thanks
SEGGER for supporting SEGGER-OB licenses that make the dock a fully functional programmer and debugger for ZSWatch. Thanks to this the project will be much more approachable for persons without a J-Link debugger, letting them have full development and debugging capabilities.