time.mktime() returns incorrect Unix timestamp on ESP32
Port, board and/or hardware
sysname='esp32', nodename='esp32', release='1.24.1', version='v1.24.1 on 2024-11-29', machine='Generic ESP32 module with ESP32. Unique ID b'\x94\xe6\x86\x13o$' (not sure what this is
MicroPython version
release='1.24.1', version='v1.24.1 on 2024-11-29',
When using this board and setting time using the ntp library thus ntptime.settime() this synchronizes the RTC to UTC using an NTP server, and it seems to be working correctly since time.localtime() returns (2024, 12, 28, 18, 11, 1, 5, 363) (UTC time). As I understand it, this should reset the real time clock to the current time. If I then set time.mktime(time.localtime()) which should provide the Unix time, it does not, instead is spits out 788726670 which is 1994-12-29 18:44:30 UTC. Can someone please explain this ? Is it a a bug? Bottom line, how can the realtime clock be set to a specific time?
Reproduction
from machine import RTC
import time
Manually set the RTC to a known time (e.g., 2024-01-28 15:30:00 UTC)
rtc = RTC()
rtc.datetime((2024, 1, 28, 0, 15, 30, 0, 0)) # (year, month, day, weekday, hour, minute, second, subseconds)
Get the Unix timestamp
unix_time = time.mktime(time.localtime())
print("Unix time:", unix_time)
Result: Unix time: 759771000 it should be closer to 1735413856.203176
Expected behaviour
Expected the unix time to be determined correctly. That is it should look something like this 1735413022.697727
Observed behaviour
The output is incorrect - see Expected behaviour result above
Additional Information
No, I've provided everything above.
Code of Conduct
Yes, I agree
docs: for time.localtime()
Hi Together,
I would remark that this description in the Doc is a little bit missleading.
'''
time.mktime()
https://docs.micropython.org/en/latest/library/time.html
This is inverse function of localtime. It’s argument is a full 8-tuple which expresses a time as per localtime. It returns an integer which is the number of seconds since Jan 1, 2000.
''''
Because on the Pico W the RTC works with the epoch since 1970.
Maybe a small redesign of this description would be perfect, my opinion.
A other point is that I want to aks what the actual status is about:
time.gmtime()
time.localtime()
Is there actually a Timezone information available in micropython?
If not Iam right that these two functions leads to the same result in time structure?
Thanks
Frank