Arduino for STM32

Hi,
your issue comes from this line: Don't know why you add it there it is not used for serialMethod

Hi,
no the core doesn't provide support for ADC differential.
You can try to use HAL/LL directly.
Here an example how to use HAL/LL:
viewtopic.php?t=110

Will check next week. I'm off until monday.

Hard to tell without the full code added.
Do you declare "MyBoards" properly?

Arduino IDE 2 have/had issue with menu update. On older version of the IDE (prio 2.3.x), the menu is not refresh at startup.
This could explain your issue.

For ref: https://github.com/rogerclarkmelbourne/ ... issues/923

I would recommend to simply declare the new boards entry and add it to the existing variant for the blackPill F411CE. Like it is done for the *PillF103: https://github.com/stm32duino/Arduino_Core_STM32/blob/3d6e84b3d8cd072f8230a4aa8bd114f5e4a70945/variants/STM32F1xx/F103C8T_F103CB(T-U)/variant_PILL_...

Discussion follow here: https://github.com/orgs/stm32duino/discussions/2348

Try to debug using Arduino IDE 2.2.1.
The latest version 2.3.x changes the debug configuration way. I will fix this within next release.

Simply enable the optimize for debugging option and you should be able to debug and see where it stucks.

You should redefine the system core clock config to properly configure the pll vs the HSE value.