STM32C552 HSI 144MHz clock

rsta · ‎2026-05-21

I created simple project using STMCubeMX2 for MCU STM32C552. I configured the clock by choosing HSIS on System MUX. When I compile and run generated code it ends in HardFault_Handler.

When using PSIS option - the same result. HSISDiv3 clock works well. When I divide HSIS or PSIS clock by 2 on

AHB prescaler it also works.

Any idea?

Thank you

Andrew Neil · ‎2026-05-21

debugging Cortex-M Hard Faults

Do you also need to configure Flash wait states at that speed?

A complex system that works is invariably found to have evolved from a simple system that worked.
A complex system designed from scratch never works and cannot be patched up to make it work.