Arduino for STM32

Hi everybody
I tested upload with ST-link and the code is ok. It works. But I saw that the monitor not works for debug. Have you some ideas ?
Thank you

Thank you GonzoG. The problem is that I can't upload program in DFU mode. This is my problem from the beginning. Little strange
And the STMCube Programmer don't see the card. In all modes. Strange too
Thank you

Thank you for all your infos ag123.
I have STM32 BOOTLOADER into Peripheral Universal Serial Bus. What this mean ?
I am more agile with Arduino IDE and I am only recent applicate to STM32 cards. May I programmed with St-link into Arduino ? I suppose is the STM32CubeProgrammer(SWD) in the config ...

Thank you ag123
BOOT and Reset not work.
Please have you a good link for st-ilnk and SWD pins uploading code ???
I will searche too
Thank you

Thank you dear friend. For me not work the reset DFU. I tried many times with BOOT and Reset without succes
Now I don't have the STM32 BOOTLOADER.
Before failed I haved the port Com into device manager too
And now I don't know what can I do.
Thank you a lot

Thank you. What do you mean if it reset into DFU, it will be in device manager as "STM32 BOOTLOADER" ?
I haved into device manager "STM32 BOOTLOADER".
I push Reset button,........nothing. I push BOOT and Reset,.......nothing
How reset board in DFU mode ? I tried everything
With Reset button don't ...

Thank you. How is possible to upload without USB support? The card worked before the last upload to arduino. Never deconnected. I maked some uploads and the last upload was the last. Resetting board while holding KEY pressed not change something. Not work for me
I always used Boot and Reset buttons ...

Thank you for your reply
It's a F411CE genuine chip. It worked before very fine. I didn't change the config. All stay the same. And with my second card works fine. My first card who has problem after wanted download the sketch from arduino. Nothing change in configuration. I test with a multimeter ...

Thank you for your reply. Yes it have the genuine st chip. I worked with this card more than 15 days without problem. After the last working it don't want to download sketch from Arduino. Blackpill seems bloqued. I have a second same card and this work fine for the moment. With the same config.
Thanks

For me I have the same problem but not valide solution. Blackpill not accept any program. I have the same config that you write. I try anything and nothing works. Thanks