RTC calibration

rajaskpathak · ‎2012-03-28

Posted on March 29, 2012 at 07:42

Hi all,

I wanted to know is there any software workaround to compensate for negative ppm values.

I am using STM32F100V8 controller. According to the rtc digital calibration manual(attached) you can only subtract the cycles(make clock slower). I just need to know how to speed up the rtc clock. Any code snippets explaining this concept would help me a lot.

Please help me.

emalund · ‎2012-03-30

Posted on March 30, 2012 at 15:34

many have tried, none have succeeded using a RC clock for the RTC. Not using a crystal produces a URTC

Erik

ColdWeather · ‎2012-04-03

Posted on April 03, 2012 at 14:32

> I just need to know how to speed up the rtc clock.

I suppose, you generate 1 second pulses/interrupts by RTC. So load a lower value into the RTC prescaler register.

rajaskpathak · ‎2012-04-04

Posted on April 04, 2012 at 14:18

Is this the only way to speed up the rtc clock?

ColdWeather · ‎2012-04-05

Posted on April 05, 2012 at 09:06

By the software - yes.