OK thanks. Basically the R4 was sold as having a built in RTC. However, it does not have a separate resonator/crystal and while it does have a new RTC library and nice functions, it has terrible accuracy (like +1 min/hour) so its basically useless. I contacted Arduino and they know its an issue but I dont think its fixable without a hardware change. I have tried using millis() in my R3 to make an ersatz RTC and while its accuracy is better its also not great.
I just happened to get access to an Elegoo ds1307 Rev 3 RTC module so decided to see how it would work, and so far I am pleased EXCEPT from time to time I get all zeroes returned.
I am using the Adafruit RTClib.h and really it all works totally fine except for this intermittent problem. Yesterday with more noodling around its seems to me it might be related to the battery, so I removed it and will play around more without it. My multimeter is dead so I cant test the battery either, ugh.
I will keep playing around. If you have any other ideas, please do speak up! Steven Lightfoot