Hi, It's about the Evbalboard EVSPIN32G4 with the STM32G4 MCU. I would like to use the two oscillator inputs PF0 (OSC_IN) and PF1 (OSC_OUT) as ADC inputs? Can I simply solder out the osci that is installed there, or does it have a function?

[BPfei.1]

MCU:https://www.st.com/en/motor-drivers/stspin32g4.html#overview

Evalboard: https://www.st.com/en/evaluation-tools/evspin32g4.html

[TDK]

If you don't need the HSE as a clock source, yes you can repurpose those pins as ADC inputs.

I can't imagine timing needs of typical applications of that board to be very precise, but you will need to make that determination for yourself.

[BPfei.1]

Does the HSE depend on the internal clock frequency of 170 MHz? Because the HSE is only 24 MHz. So what as example will decrease?

[TDK]

One can achieve 170MHz without the HSE present.
I would recommend looking at the clock tree in CubeMX or the reference manual for deeper understanding. Specifically the use of the PLL as a clock source and it’s possible inputs.

[Nikita91 · Accepted solution]

"Does the HSE depend on the internal clock frequency of 170 MHz?"

It is not the HSE that depends on the internal frequency, it is the opposite: The internal frequency of 170 MHz can be obtained from the 24 MHz frequency of the HSE and the internal PLL, which multiplies the frequency.

If you want to use the PF0/PF1 pins as GPIO, you must configure the system clock to use another clock source, such as the HSI.

Use CubeMX to interactively explore the clock configuration of the G4, and look at the alternate functions of PF0 and PF1.

[BPfei.1]

With the CubeMX it was possible to use the internal HSI and with the right adjustement of the dividers, it was possible to keep 170 MHz.Thanks 🙂