Go Down

Topic: DS 1307 stays behind in time day by day... (Read 2396 times) previous topic - next topic

Jack Christensen


This story seems appropriate here. The contractor was the dad of someone I used to work with...


"Man with watch always know what time it is. Man with two watches never quite sure."
MCP79411/12 RTC ... "One Million Ohms" ATtiny kit ... available at http://www.tindie.com/stores/JChristensen/

petethegeek


Do you have any ideas on how I can synchronize my RTC with my PC system time?


Be careful. It's a very slippery slope you're on...

http://www.wired.com/science/discoveries/news/2007/12/time_hackers?currentPage=all




zipwize

You should check your crystal frequency. I believe the DS1307 uses the external 32.768kHz crystal. These are temperature sensitive and the cheaper ones tend to be less accurate.
There are better TXCO with a self heated or stabilized reference. You might use a trim capacitor on X1 or X2 to trim the frequency. You might just swap out the crystal and get better (or worse) synchronization. I hope this helped.

Go Up