Arduino for STM32

You can change those but drivers will stop loading, as they use VID and PID values to recognize device.

There a few files where those are set. The easiest way it to search all core files for VID or PID value (eg. using Unreal Commander or Total Commander).

With all options enabled stm32duino will need quite a lot of flash and RAM.
It's because it's made to be easy to use and not resource efficient.
You can disable unused peripherals and this will save some flash and ram:
https://github.com/stm32duino/Arduino_C ... figuration

it's a version of stm32duino from which each MCU/board is supported.

It's H5 board, not F1.
You probably won't find a compiled USB bootloader for it, you will have to compile one yourself.
analogRead() is really slow on H5/H7 MCUs.

Did you try to use this library ??

Not enough information.

1. are you 100% sure the LED shouldn't be on ??
2. did you set it up to have com port ??
3. do you connected it to correct usb port ??
4. my crystal ball run out of magic juice... which board you're talking about... ??

To program stm32f103c8t6 blue pill via uart you need to set boot0
and you need stm32cubeprogrammer (or some such programming util)
https://www.st.com/en/development-tools/stm32cubeprog.html
^^ this is from ST (you can consider that an official programming tool)

Isn't that exactly what he wrote ...

Wrong subforum - you're asking about STM32 and posted in STM8.

This won't be done automatically by MCU (with one or a few simple commands).
First you need to measure length of pulses or time between them and by comparing them find the gap to get your program synchronized. Then you can count pulses ...

STM32F103 has a USB interface built-in. Those are PA11 and PA12 pins. But it does not have USB bootloader (called DFU by STM) so you cannot flash firmware using USB without software bootloader (like HID bootloader )

It looks like those jumpers (not resistors) are under CH340 and by default are not ...

What are your settings for UART and USB support in Arduino IDE ??