I'm running the DS3231 clock module from ebay with the Arduino nano and it seems to run fine, reads out the time and temperature OK, until I pull the power.
Then it loses the time and starts over when repowered. There is no time reset in the code (commented out and reloaded.)
I thought the battery provided backup power for this so it wouldnt lose time. I mean thats the whole idea of a RTC. I checked the battery and it looks good at 3.7v.
Any ideas on what the problems is here. TIA.