Thanks for the information and reference. I’m impressed that you got the v20 RTC to work! That’s the main reason I switched to v21 (the vendor even refunded the v20).
I’m using my Stalker/Xbee for the same reason. One other tip I read was to configure the Xbee as a end node (not router/end node) because as a router it always has to be on to route potential messages it receives. In as an end node, it only has to wake up with firmware when it has to send a message.
Cheers!