weather-station/Arduino/outdoor-weather-station/02_sleep.ino

void deepSleep() {
	hideProgress(); // Make sure the LEDs are turned off

	debug("Milliseconds awake: %d", millis() - wakeTime);
	int64_t sleepTimeMillis = SLEEP_TIME_MS - (millis() - wakeTime);
	
	debug("Going to sleep for: %d milliseconds", sleepTimeMillis);

	// Do it again to account for the time the serial printing might take.
	sleepTimeMillis = SLEEP_TIME_MS - (millis() - wakeTime);
	esp_sleep_enable_timer_wakeup(sleepTimeMillis * 1000);
	esp_deep_sleep_start();
}