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Forum Index : Microcontroller and PC projects : the drift of your rtc is...

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plasma
Guru

Joined: 08/04/2012
Location: Germany
Posts: 437
Posted: 09:25pm 12 Feb 2016
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hi,

a friend of mine needs a user defined clock , this time without internet connection so i can only use a rtc modul or a gps module here .

so i ask : how big is the drift of your rtc over a year?

 
PicFan
Senior Member

Joined: 18/03/2014
Location: Austria
Posts: 133
Posted: 11:03pm 12 Feb 2016
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I have since 3 months a DS3231 in use. The difference is presently about + 0.5sec compare with DCF-77. It is the Standard-Chip of the DS3231 !Edited by PicFan 2016-02-14
 
plasma
Guru

Joined: 08/04/2012
Location: Germany
Posts: 437
Posted: 10:01pm 13 Feb 2016
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thx picfan
 
Gizmo

Admin Group

Joined: 05/06/2004
Location: Australia
Posts: 5118
Posted: 02:13pm 22 Feb 2016
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I bought one of these from ebay...
PCF8563-RTC-Board-CMOS-PCF8563T-Real-time-Clock-Calendar-Module-Development-Kit

Drift is about 4 minutes a day!

Funny how a cheap battery powered clock mechanism can not loose a minute a year, but a dedicated RTC can loose minutes a day.
The best time to plant a tree was twenty years ago, the second best time is right now.
JAQ
 
palcal

Guru

Joined: 12/10/2011
Location: Australia
Posts: 1989
Posted: 06:03pm 22 Feb 2016
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I've been running a DS3231 module from EBay so maybe not genuine. It is 8 seconds fast compared to GPS in 2 months.
Paul.
"It is better to be ignorant and ask a stupid question than to be plain Stupid and not ask at all"
 
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