We are using the STM32U5 MCU and its internal RTC in our project.
We are facing an issue where the RTC time sometimes goes beyond 24 hours — for example, we observed a timestamp showing 37 hours.
The RTC is configured in 24-hour format, and we have initialized the RTC and its time format correctly as per the reference manual and HAL documentation.
Also, After running for 23:59:59 seconds, the time changes to 24:00:00 instead of 00:00:00, and the week day has not been incremented.
The main challenge is that this does not happen consistently. We see such out-of-range values only randomly, which makes it difficult to identify the root cause.
Has anyone faced a similar issue with the STM32U5 RTC? Could you please suggest possible causes or solutions, or any checks we should perform to debug this behavior?
