Thanks for sharing the code !
Can you please explain these 2 lines of code!
di.DriftDays = 1000; // valid value 0 to 65,535
di.DriftSeconds = 2725; // fine tune this until your RTC sync with your reference time, valid value -32,768 to 32,767
also how to calculate these values , if my clock is 6 sec/day fast.
Please explain any other code lines related to correction !