ESP32 Forum

Since my experiences in an earlier esp32 project i was sure that the millis() value isn't maintained over light-sleep. And i had to use the RTC myself to determine the sleep time.

Now more or less by accident i recognized that the millis() value is indeed corrected after wakeup from light-sleep.

Does this behaviour changed over idf or arduino Versions?
Are there any requirements to make this work which are now met by accident?

It is possible that this hasn't worked in the first arduino-esp32 release, v1.0.0, which came out in July 2018.

arduino-esp32 uses esp_timer_get_time IDF function to implement millis, and esp_timer_get_time has maintained time in light sleep since IDF v3.1, released in September 2018.

If you have observed this behavior in later releases of arduino-esp32, then I don't have an explanation for this. But maintaining the 'millis' value in light sleep is now the expected behavior!

Thank you for this information.

Maybe i can figure out which versions were in use. Just for curiosity.