I created an ESP8266-based project which is a battery-powered LCD information board. As it's battery-powered, I'm concerned about energy consumption.
Most times the circuit is inactive (LCD powered off, and so should the ESP8266 be). But as ESP.deepSleep() (and its native SDK counterpart) only allow a deep sleep of about 1h, the device currently wakes up every hour just to fetch another "go to sleep" command - even if it should sleep 4 whole days.
My question is as follows: Consider the ESP just got a command to sleep for 4 days. Is it somehow possible (and reasonable) to store this information in RAM or EEPROM, so it would still wake up each hour, but wouldn't need to use WiFi but locally retrieve the stored value of hours to sleep, decrease it and go to sleep again? Is RAM preserved during deep sleep and how could I store this value then? Isn't EEPROM a bad idea due to a fast wearout?
Thanks in advance!