Is it possible to guide the HSE clock to MCO pin?

ledi7 · ‎2024-09-22

Hi,

I would like to use the STM32WBA55 controller and forward the clock of the HSE to the MCO pin. The data sheet states that this is only possible for internal clocks:

Clock-out capability:
– MCO (microcontroller clock output): outputs one of the internal clocks for external
use by the application. (only available in Run, Sleep and Stop mode)
– LSCO (low-speed clock output): outputs LSI or LSE in all operating modes.

According to the block diagram (see attachment), however, this should be possible.

MHoll.2 · ‎2024-09-22

Hi,

Yes this should be possible, see RCC_CFGR1 register MCOSEL bit's in RM0493:

Martin

Amel NASRI · ‎2024-09-23

Hi @ledi7 ,

To confirm the answer of @MHoll.2 , here a ready to use example: STM32CubeWBA/Projects/NUCLEO-WBA55CG/Examples_LL/RCC/RCC_OutputSystemClockOnMCO.

Check the readme file to understand how it works.

-Amel

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