One thing I found interesting is I saw F_CPU=100000000 somewhere which looks like 100MHz. That leads to the topic of chip configuration:
In CubeIDE I got drenched in dozens of options to setup the chip’s clock and USB and USB-DMA and much more.
(For USB to work I need a CPU clock of 96MHz as this leads to a USB-clock of 48MHz. USB is verrry picky with regard to clock accuracy.)
And when I configure too many timers and USB and ADC concurrently I get visually alerted that they’d conflict, looked like a very smart system.
Furthermore when I tick USB and USB_CDC I get quite some source files automatically added to my project plus a dozen lines long Initializing code for Clock, USB etc.
So: where is all the CubeIDE chip configuration done in PlatformIO?