Bluetooth steering wheel hub: TiHUBv2

Features I hope everyone can improve:

Add dual-sided LEDs to each dual-sided button, single color is fine, dim, possibly driven by a MOSFET from the battery.
Add a side rotary encoder near the thumb.
Replace the encoder on the lower right side with a rotary band switch for switching modes (may need to increase the number of channels through different resistance values ​​or shift registers).
Change one of the buttons to a seven-way joystick.
Add a battery level display (detecting the current reserved space for surface-mount resistors), which can be used in conjunction with the first LED flashing to remind the user.
I welcome suggestions for other new features to improve the user experience.

If these features are usable, I will merge them into the main branch. Let's work together to promote the progress of the open-source community and the simulator. Thank you!
 
 
Manual: TiHubV2 User Manual + BOM (qq.com)
Introduction Video:
TiHub v2 Bluetooth Wireless HUB_Bilibili_bilibili
 
Donations welcome:
The main features of the new steering wheel hub :
 
First, in terms of design, it has changed from one large board to two small boards connected in opposite directions, and the size of the boards has been just reduced to 10x10 cm, making it easier to prototype with JLCPCB.
Secondly, the main controller has been changed from ESP32 to NRF52840, which significantly reduces power consumption and greatly enhances battery life, turning the previous two or three days of battery life into almost unlimited battery life.
Thirdly, the previous mechanical keyboard switches have been replaced with simple 12x12 buttons with button caps, which feel quite good and look very professional after applying stickers.
Fourthly, the shift paddles that previously required wire connections have been replaced with onboard connections, making the assembly process much easier.
 
Currently, the cost of this set is very low, and since it uses pre-built modules, everyone can solder them themselves. Like the previous version, all the code and 3D models will be open source. Friends who are interested can make one and try it out, or I will also release the pre-built kit later.