Posted on March 05, 2018 at 07:57 
Hello there,
I am using an STM32L4 family MCU. In an application, the RTC peripheral is utilized and clocked from an external crystal:
The problem I have noticed just now is that with time, the RTC timer looses sync. It is not easy to notice in short periods of time, but after leaving the application to log time for entire weekend, I noticed that the RTC timer is over 20 minutes later after my PC timer (they were both synced before the weekend).
What could be the cause of this problem? Its hard to believe for me that the RTC timer is simply this low precision, as I am using an external crystal. I would appreciate all help.
#precision #stm32l4 #rtc Note: this post was migrated and contained many threaded conversations, some content may be missing.
Posted on March 19, 2018 at 12:37
Hello JLuc,
Please find extract from STM32L4 training material related to clock sources parameters, including their accuracy.
Regards
Szymon
