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DS1307 Running Slow
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DS1307 Running Slow

by nabelekt on Tue Nov 21, 2017 8:07 pm

I am using the DS1307 breakout board listed here: https://www.adafruit.com/product/3296.
It is working fine for me, except that the clock is running slow. In a couple short experiments, it looks like the clock is losing 3.15-3.3 seconds per hour. This works out to about 9.5 minutes in a week.

Is this normal for the DS1307? The page for the precision clock at https://www.adafruit.com/product/3013 might explain why this is happening, but I feel like this is a lot of time lost. Do I have a faulty clock?

Thanks.

nabelekt
 
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Re: DS1307 Running Slow

by adafruit_support_bill on Fri Nov 24, 2017 7:23 am

Using the 'millis' version of the library, you are not actually reading from the RTC. See the related discussion here: viewtopic.php?f=41&t=126944

adafruit_support_bill
 
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Please be positive and constructive with your questions and comments.