Stm32Dev - first version
This version was a learning experience and it is crap, - check out Stm32Dev - rev. b instead!
My interest in STM32 got triggered by a "failed" project using an ESP32 processor. One of the requirements of that project was extremely precise - and quick - SPI timing and I simply never managed to implement that in a controlled manner. Because of that and the fact that JLCPCB carries a lot of STM32 variants in their parts inventory, I decided to make some experiments with these processors.
Armed with the datasheet it was time to hack a schematic together in KiCAD: