ESP8266 Community Forum

rtc_time2 = system_get_rtc_time();

and

system_rtc_mem_read(0, &rtc_reg_val, 4)

both return 4bytes.
Now RTC's often have registers that contain a representation of the day,month, year, hour, min, and second
system_get_rtc_time looks like counter in the way that system_get_time() returns a 32bit counter.

Question:
Is the esp8266's internal RTC just a counter incremented on a quanta of instruction cycles that differs from the
system_get_time() counter in only in the fact that it keeps running during sleep?

Or is it a RTC like a Dallas DS1307 that has day,month, year, hour, min, and second?

It's a counter. Probably run by a hardware timer. Check the Espressif SDK PDF that was posted on this forum very recently.

Mine is not running during sleep

Using deep_sleep and waking automatically, the RTC clock time is being reset at the same time as the system clock

System time = 6212168
RTC time = 1045677

next time around ..

System time = 6210447
RTC time = 1045436

and on it goes..

According to specs found at http://bbs.espressif.com/download/file.php?id=520 , there is no internal RTC. So, emulation is all done in software.