Setting the time on the DS3231 Real Time Clock from the PC time.

First make sure your PC time is set correctly. Next wire up the DS3231 to your Ardunio Nano. Then install the battery. Run this Time Set program only when you need to set the time in the RTC.

DS3231    Nano
 GND   >  GND
 VCC   >  5v
 SDA   >  A4
 SCL   >  A5