APM/STM32F103CxT6 minimum system board

This project is intended to consume the remaining materials of my DIY keyboard. The board has a large open space. If you need other packaged components, you can modify it yourself.
Blue File Theme? If you don't like it, just delete the silk screen. The pin
spacing is 600mil, which can be inserted into the perforated board and breadboard.
The 5V pin is connected in parallel with the USB power supply pin. The DIY keyboard can directly connect the 5V pin to power the RGB light. The current depends on your USB current .
This project does not have any protection devices. Overvoltage, overcurrent, backflow, and surge may cause damage! Please note!
 
Design error, VBAT pin is not brought out! Directly connected in parallel with VCC! (Only affects the sleep function) It is inconvenient to modify for some reasons, please be aware!
 
If you use the STC function, please use a load capacitor of 6pF for the 32.768kHz crystal oscillator! This project takes typical values ​​according to DATASHEET.
The following is taken from the DATASHEET of APM32F103CBT6:
 
If you use STM32, please change the two 22r resistors in series on the USB to 0r. For specific reasons, please refer to the 3.1 section of ST's AN4879 document.
 
The choice of two LEDs is relatively free. The power supply voltage is 3.3V. You can choose your favorite color and a suitable current-limiting resistor.
I use a white light and a current-limiting resistor of 5.1k. It can be used for reference (indoor lighting environment on a rainy day):
The following are some physical pictures (first edition). Some of the silk screens are too small to see clearly. This has been modified, but the effect has not been verified by proofing: