Arduino for STM32

According to this link you do it in CubeMX: https://controllerstech.com/stm32-usb-host-hid/

I would use a F4x1 pill and some apps already available on the net, like this:
https://damogranlabs.com/2018/02/stm32- ... -keyboard/
g**gle is your friend

Wilkommen Volker,
please, if you haven't done that before, read this first:
viewtopic.php?f=2&t=301

DMA cannot do average, it just saves values in an array or one variable.
If you want average of some values that would inevitably involve CPU processing either in an ISR or on main level.

I think the main issue is to find a universal tool which instantiate the USB DFU interface on all OS which allows the upload.
And Java is the one which can be used independent on the platform. Unless one develop different tools for each platform in part.

The main development target IDE is Arduino.
If Arduino IDE changes the behavior, then this will be also adapted, but other IDEs will not be taken into account.
You cannot support every kind of specific behavior for every IDE.

Which resolution you want to achieve?
If not critical then you can make it without any specific timer, just user micros() for time measurement.
In this case, taking into account other system interrupts like systick and USB (if you use it) you better use median instead of mean of the values.

And which core?
If you don't know, then post a picture of the selected board in Arduino IDE.
Please also post a link to the library.

viewtopic.php?f=2&t=301

Which core and which LCD library do yo use?

You have to install the serial driver from ST: https://www.st.com/en/development-tools/stsw-stm32102.html This will allow you to use the USB as serial port. To program the board you need either an STLink probe or you have to install a bootloader (for this you need anyway an STLink first...). Please ...