STM32F042: External clock and clock output

[harald]

As described before (https://community.st.com/s/question/0D50X00009sWdDqSAK/stm32f042-bootloader-activation) I want to use 2 STM32F042 as CAN controller. So far I planned to use the internal HSI RC oscillator, but a +-5% tolerance seems critical for CAN clock accuracy. Using a crystal is not possible due to size and cost limitations.

I can create a 8Mhz signal from host CPU and use this as system clock. I would even like to use clock output of one STM32 as clock input of the other to avoid having my host CPU need to drive both inputs.

Is that possible? How do I configure this? When trying to enter this in CubeMX, I get errors: When entering "8" in Input frequency it is getting overwritten with 0.0000080, when writing 8000000 I can't leave the clock fonfiguration tab.

In neither cases I can select a clock output.

Any recommendations?

Thanks, Harald

[Tesla DeLorean]

Dupe https://community.st.com/s/question/0D50X00009sX1XLSA0/stm32f042-external-clock-and-clock-output

[harald]

What does dupe mean?

Regards

Harald ​

[waclawek.jan]

Duplicate post.

JW

[Tesla DeLorean]

Second identical post, cited. Presuming issue with forum/submission. Implying conversation should stay on the other one, rather than this one.