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How to calculate the PPM deviation for 512Hz?

Hi ST team,I referred the Application notes from the ST's for RTC temperature compensation Using STM8AL3189 MCU , Which has both positive and negative ppm compensation using CALM and CALPFrom the APP notes, ACC(ppm) = crystal deviation + k * (T -T0)^...


RTC temperature compensation clarification

Hi Team,I need some help to understand what I am doing is correct or wrong. A required guide from ST's expert Basically working on RTC temperature Drift compensation, so I have referred the RTC temperature compensation APP document from ST's The link...

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My question relates to the M41T81 Real Time Clock. Wasn't sure which topic to post in so picked this one since the RTC interfaces to an 8 bit micro. My problem is that the RTC doesn't always recover from power-down correctly.

The data sheet for this part says that after power loss the HT bit is set, and any reads of the clock will return the time of the last read. Then after the HT bit is cleared one should be able to read the current time since the clock is battery backe...

GDick.1 by Associate
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Why RTC_WakeUpCmd can fail?

In the STM8L SDK, the RTC_WakeUpCmd()  function can return an ERROR if the WUTWF bit fails to be set after a delay.  In the RM there's no mention of how and why this situation would occur.Why RTC_WakeUpCmd can fail?Thanks,Gabriel

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GBert.2 by Senior
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RTC clock not starting consistenly

Hi everyone, I'm using the STM8L152R8 Nucleo board and trying to get the RTC running on the LSE clock. It works but only inconsistenly, about 2/3 runs error out in the RTC_EnterInitMode function of the SPL the below line. RTC_EnterInitMode is called ...

TConl.1 by Associate II
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What is the reliability of the RTC?

Posted on April 21, 2018 at 14:35Hello everyone,Very much I ask to respond who knows. Whether methods are applied of providing increased reliability of real-time timers, for example redundant coding or majority calculations. And what are the values ...

RTC problem

Posted on November 19, 2015 at 23:22I'm working on some code to set the RTC alarm, and I've gone through all the resources I can find on how to set this up correctly, but it's just not working. If you could take a look and see if I've missed anythin...

RTC smooth digital calibration

Posted on February 28, 2015 at 19:25I've been called to help support a project using an STM8.  They are having problems with RTC clock drift, a couple of seconds a day, and showed me section 24.3.8/9 in the RM0031 datasheet.  I found the document AN...