I have the STM32F302R8 MCU board.l Its user manual is here.
There are two crystal oscillators on the board. X3 is missing and X1 seems to be used for the small debugger microcontroller (circled in red below):
In STM32CubeMX I can set external high speed oscillator as the main clock, but it seems X1 is used only for the debugger. If so, how come I can set the clock as HSE? Does that mean this X1 can be used for the main microcontroller? Is there a way to figure out this from the manual?
Clock configuration I can either select:
In the above cases is LSE connected to X3 which is missing? In the second case is HSE the main system clock and connected to X1?