Leta

The name: Leta is summer in russia. It is the time that i started to make my own wrist watch.

Oled wrist watch using Stm32f1 with mini RTOS and Monochrome GUI

Demo

demo_leta.mp4

Link youtube:

https://www.youtube.com/watch?v=F7zo0RkRJ88

Schematic

• Microcontroller: Stm32f103xx, 128 kB ROM, 20 kB RAM. Build-int RTC.
• IMU: MPU6050, HCM5883L.
• Temp and humid: HTU21D.
• Bluetooth: RF-BM-4044B4(RF-Star).
• Display: SH1106 oled 1.3" 128x64.
• Power: TP4056 charger IC, regulator 3.3V AP2112.

PCB

• 2 layers
• USB interface
• 1 port SWD interface
• 4 buttons

Enclosure

Program layers

AK-mOS

This project uses a mini RTOS (AK-mOS) which written by me for AK-base-kit (ARM cortex M3).

The kit you can check out here:

https://github.com/epcbtech/ak-base-kit-stm32l151

The mini RTOS has following features:

• Preemptive scheduling
• Round-robin scheduling
• Inner tasks communiation
• Software timer

More detail about it:

https://github.com/snoopy3921/AK-mOS---The-simple-RTOS-on-AK-base-kit

This mini RTOS was created for learning purpose with context switch based on freeRTOS.

Im hoping this OS can be used more to test stability.

Oled GUI

To control oled display with rich animating. I wrote the library to increase experience on UI.

The UI has some widget like:

• Switch
• Label text
• Check box
• Bitmap
• Indicator
• Pop-up notify
• Slider

Animating can do these things to widgets:

• Fading
• Moving
• Resizing

Check out here is more detail about my GUI:

https://github.com/snoopy3921/Monochrome-Oled-GUI

References

These links below are materials which helped me a lot when bulding my project:

• https://github.com/ZeekiChen/iWatch-v2.0
• https://github.com/lvgl/lvgl
• https://github.com/Sheep118/WouoUI-PageVersion
• https://github.com/epcbtech/ak-base-kit-stm32l151
• https://github.com/FreeRTOS/FreeRTOS-Kernel