Open Source Transparent Watch - T1

Video

Next, I'll add more low-power processing, as well as more types of clocks that show different clocks whenever I wake up my watch

I've been able to get data on BMA423, but some features don't work. 

I temporarily purchased some QMA7981 as an alternative. 

But while I wait, I'll continue to see what the problem is.

After receiving PCB v1.1 and welding, everything is working fine.

Next I'll start writing code.

I printed the 3D case and the assembly worked well.

Version 1.0 has some minor issues. 

In version 1.1 I modified the position of the connector.

Use lceda to open the source file.

I finally received the PCB today.

The schematic and pcb have been drawn and are ready to be sent to the manufacturer

There are two acceleration sensors, one of which you can select as needed.

Because ch573 does not support hardware IIC, the SPI interface is used to communicate with the accelerometer.

If you have any better suggestions, please let me know.

A few days ago, I received the CH573 development board from WCH, so I'd like to try this chip.

and here is some overview of the chip：

• 32-bit RISC processor WCH RISC-V3A
• Supports the RV32 IMAC instruction set, single-cycle multiplication and hardware division
• Built-in 18K SRAM, 512K Flash ROM, ICP, ISP and IAP support for OTA wireless upgrades
• Integrated 2.4GHz RF transceivers and baseband and link control to improve optimized protocol stack and application layer APIs to support networking
• Supports 3.3V and 2.5V power supplies, built-in DC/DC conversion, and 0dBm transmits power with a current of 6mA
• Various low power modes: Idle, Halt, Sleep, Shutdown, built-in battery voltage low voltage monitoring, minimum sleep current 0.3uA
• Built-in USB controller and USB transceiver for USB 2.0 full-speed and low-speed hosts or devices
• Built-in real-time clock RTC supports timing and triggering modes 
• An 8-channel 12-bit ADC-to-digital converter is available to support 8-channel touch keys 
• Provides 4 sets of 26-bit timers, supports capture/sampling, supports 4 26-bit PWM outputs, and supports 6 8-bit PWM outputs 
• Available in 4 sets of stand-alone UART, compatible with 16C550, with a maximum communication port rate of up to 6Mbps 
• Available in 1 set of SPIs, built-in FIFO, support for Master and Slave modes 
• Built-in temperature sensor 
• Available in 20 GPIO, 4 of which support 5V signal input, all GPIO support interrupt and wake-up functions 
• Built-in AES-128 plus decryption unit, chip unique ID 
• Package: QFN28_4X4

I've ported the u8g2 library to this chip.