The PF0 pin of STM32F030R8T6 can't use interrupt function?

[choro]

I use STM32cubeMX tool, generate interrupt function, compile and program successful in Keil V5. But this function doesn't work. How to solve the question?

[S.Ma]

Are we talking of EXTI interrupt source? Checklist:

• If PF0 is used other than GPIO, in CubeMX, EXTI and peripheral Alternate Function don't work as stacked pin. The direct HW register programming works fine.
• If other GPIO port 0 is used: In EXTI you can't have say PB0 and PF0 as interrupt source. Only one per pin number.
• Run the debugger, run the code, stop it and view the EXTI/GPIO registers manually. Modify manually the registers then let the code run to see if you find the culprit. Avoids lots of guessless recompile cycles.

[choro]

Thanks a lot.

In last week, I check the schematic of STM32 Nucleo-64 development board with STM32F030R8 MCU, found the pin connect to the MCO pin of ST-Link, I guess that it is the cause of the question. But I don't understand the function of the MCO pin?

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[waclawek.jan]

In addition to KIC's checklist, PF0 is OSC_IN, so if HSE is switched on (see Using the HSE or LSE oscillator pins as GPIOs subchapter in RM), it is unavailable for any other use.

JW