2018-09-04 04:37 AM
I was using stm32f429 and ported my code to stm32f777. In F429 the rtc was working accurately but in F777 it is lagging by about 1hr a day approx. The hardware is same for both the MCUs and using the internal RTC
2018-09-04 07:57 AM
What do you mean by "internal RTC"? Do you use LSE as RTC clock source, and have a 32.768kHz crystal connected?
JW
2018-09-04 05:34 PM
Use a proper chip for time of day...
this one is good for less than 2Minutes error per year !
DS3231
2018-09-05 09:15 PM
yes, i am using LSE as RTC clock source, and have a 32.768kHz crystal connected.
2018-09-05 11:24 PM
Sounds like you've got the prescalers set wrong.
2018-09-06 01:35 AM
But RTC was working fine in STM32f429 with same settings
2018-09-06 02:12 AM
Ok, so why do you need our help?
Perhaps route LSE out the MCO pin and scope it to confirm frequency.
