ZSWatch is based on Zephyr Project RTOS, hence the name ZSWatch – Zephyr Smartwatch.
It was recently released andl open development of the ZSWatch project, which is the development of a smart watch based on the Nordic Semiconductor nRF52833 chip, equipped with an ARM Cortex-M4 microprocessor and compatible with Bluetooth 5.1.
It is mentioned that Smartwatch-specific software and hardware are developed specifically for the project, since the schematic and PCB design (in kicad format) is provided in the repository and is available for download, as well as a model for printing the case and docking station on a 3D printer.
The software is based on the open Zephyr RTOS that supports pairing of smartwatches with smartphones based on the Android platform.
Three buttons are provided for control, and sapphire crystal is used to protect the screen. A second, improved model is also being developed, distinguished by the use of a more functional nRF5340 chip based on the ARM Cortex-M33 processor and the presence of a touch screen.
On the part of software, it is written in C language and runs under the operating system in real time (RTOS) zephyr .developed for IoT devices under the auspices of the Linux Foundation with input from Intel, Linaro, NXP Semiconductors/Freescale, Synopsys, and Nordic Semiconductor.
The Zephyr core is designed to consume minimal resources (from 8 to 512 KB of RAM). Only one globally shared virtual address space (SASOS) is provided for all processes.
Application-specific code is combined with the specific kernel of the application to form a monolithic executable that will be loaded and run on specific hardware. All system resources are determined at compile time and only those kernel features that are required to run the application are included in the system image.
It is also worth mentioning that about synchronization with Android devices, it is mentioned that there is an excellent Android app called GadgetBridge that handles everything that is needed on the phone, such as notification management, music control and much more.
The ZSWatch right now claims to be one of the supported smartwatches on Gadgetbridge, following the same API it does.
On the part of the hardware components that make up The project mentions the following:
- Hardware features in ZSWatch v1
- nRF52833 BLE chip (u-blox ANNA-B402 module).
- 1,28″ 240×240 TFT IPS circular screen with GC9A01 controller.
- Accelerometer for step counting, etc. (LIS2DS12TR).
- Use of pulse oximetry and heart rate (MAX30101EFD).
- Vibration motor with haptic controller to provide better vibration control (DRV2603RUNT) .
- 8MB external flash (MX25R6435FZNIL0).
- Battery charger and battery monitor (MAX1811ESA+ tab, TLV840MAPL3).
- 3 buttons for navigation (previous/next/enter)
- 220 mAh Li-Po battery.
- Sapphire crystal to protect the screen.
And for the part of thes main software features of the project the following stand out:
- Interaction with a smartphone and control through the Android application GadgetBridge.
- A graphical interface that can display the clock, date, battery charge, weather forecast, steps taken, number of unread notifications, and heart rate.
- Support for popup notifications.
- Expandable menu with settings.
- Application selection interface. Of the programs, a configurator and a music playback control widget are proposed.
- Integrated pedometer and heart rate monitor functionality.
- Support for Bluetooth Direction Finding technology to determine the direction of the Bluetooth signal, allowing you to use the watch as a tag tracked by any u-blox AoA board.
From the part of the future plans for the development of the project it is mentioned that it is planned to include a heart rate application, update the Bluetooth pairing system and redesign the graphic casing in the form of a replacement application.
Finally for those interested in the development of the project, they should know that this is distributed under the MIT license and they can consult everything about it at the following link.