There’s no RTC on this board. You have to use an external one (usually I2C) and use an device tree overlay to map it to a driver. There’s two RTC overlays aleady available in the libretech-wiring-tool’s ldto command.
DS3231 is an I2C based RTC. You can run sudo ldto enable i2c-ao and then sudo ldto enable i2c-ao-ds3231. This will create the device for you to play with and test if the hardware is properly hooked up to the i2c-ao pins.
After testing, merge the overlays using sudo ldto merge command to make it apply on boot.
Ok I have it working. But just so everyone will know. It worked a while then stopped as I was working on it. I found out it unmerged itself.
So the overlays can unmerge themselves if you boot without the RTC swapping cards or something? Requiring you to merge them again. Might be better to use a start up script to enable on every boot and not use merge at all. I know its still beta.