Thanks for the fast reply. I know that the hard fault comes from very end of the function HAL_RCC_OscConfig()Where the following if statement is true:// ... inside HAL_RCC_OscConfig().../* Do not return HAL_ERROR if request repeats the current config...

HiLuckily I just stumbled upon this older discussion since I had the same issue. Note that setting RCC->CFGR = 0; before calling SystemClock_Config() solved my issues but I do have some follow-up questions.I am using a NUCLEO-L552ZE-Q (default config...