Arduino for STM32

I want to create a software serial on the pa3 and pa5 pins because I want to use the board I created earlier. I tried standard software serial but it doesn't work. I apologize for my poor English. And I ask for your help.

I do not recommend it, there are 3 USARTS, surely you can cut& jumper, but:

https://stm32duinoforum.com/forum/viewt ... _3428.html (Roger's core)

Ray


References to common boards:
- blue pill https://stm32duinoforum.com/forum/wiki_ ... _Pill.html
- black pill: https://stm32duinoforum.com/forum/wiki_ ... _Pill.html
- Robotdyn black: https://stm32duinoforum.com/forum/wiki_ ... _Pill.html