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PC14 behaving strangely in STM32L431



I am using PC14 in STM32L431 as an output and getting output 1 even if I make the pin Low .

I have connected VBAT pin to VDD . And the PC14 Pin is pulled up with 10K Resister to VDD.

When I check the out put without pull up it is showing 0 ,but the moment it is connected to VDD through 10K it showing High.

VDD is 3.3v


The RTC can override the GPIO settings. Are you using RTC?

If not, show values of the relevant GPIOC registers to verify it's configured correctly. Specifically, show the values when the output is set to 0 but you still see a 1 on the output.

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PC13, PC14 and PC15 are in the low power domain. The IO cells have minimal drive current.

Per TDK, make sure the RTC isn't taking these for OSC32 IN/OUT, that you don't enable/start LSE

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Read out and check/post content of RCC_BDCR and RTC registers.