Why is my MCO only outputting 8MHZ despite configuring for PLL?

[Maaz1]

Hi all

For some reason my MCO(PA8) only outputting 8MHz despite me configuring it for 60MHz

I am completely baffled because I have followed all the correct register settings(as far as I am aware) for the clock configuration, and have followed the clock diagram from the stm32cubeide

I'm working on an STM32U5G9x and its my first time working on such an advanced topic, so apologies beforehand. 

Kind regards

[KnarfB]

Where is MCO in your clock settings diagram?

Does your LA have enough sample frequency or do you see an alias frequency?

Looks like a screendump from "logic" which is often used with simple 24 MHz LA's.

hth

KnarfB 

[Maaz1]

Hi

I have tried it with the oscilloscope and it still gives 8MHz. My MCO is PA8. I configured it myself in the file I gave, but it should output more than 8MHz at the very least

[Andrew Neil]

What if you try configuring it in CubeIDE ?

[Maaz1]

I still get 8MHz

[KnarfB]

and if you increase the MCO prescaler considerably to lower the freqs?

[mƎALLEm]

Hello,

I suppose 60MHz is your HCLK clock?

If yes, did you set this configuration?:

[Tesla DeLorean]

>>STM32U5G9x

Is this on a Custom board or one of the ST development boards?

Show attachment point and related portion of schematic.

Do you have a serial port working on this board? Can you output diagnostics / telemetry via printf()?

Try dumping register content for RCC, GPIOA, etc. Unpack PLL and clock settings, decode vs MSI / HSI / HSE_VALUE

Register Level code, you've got to own the debug task

[Andrew Neil]

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@Maaz1 wrote:

I still get 8MHz

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Show your Cube setup!

You could post the IOC file...

[Maaz1]

This is my ioc file