dear all, I was wondering if we can have precise and accurate time periods over deep sleep cycles.

I have a sensor node which should measure every 5 minutes. Depending on temperature, two nodes drift 10 to 20 seconds apart each cycle.

I'd like this, so that the sensor node can measure and log to internal file with timestamp, and every 24h get NTP time again and transmit the logfile. Currently, I fire up the WiFi every measurement which of course wastes a lot of power.

Node MCU has this apparently:
https://github.com/nodemcu/nodemcu-firmware/blob/master/docs/en/modules/rtctime.md