For sometime I have been using an ESP32 where I need accurate time information. I have been using the ESP32 time.h functions. I was not aware until recently that once the ESP32 has synchronised with the NTP time the time functions rely on the internal ESP32 RTC and if not updated from time to time c…

[image] fairfield87: I have modified the ESP32>Examples>Time>Simple Time example to include a method to regularly synchronise the ESP32 RTC to NTP time. as far as I know the default update time is 1h anyway. 15 secs is a really overkill. Please modify your example to something more reasonabl…

[image] fairfield87: the output is: (I am based in the UK hence time on the left is GMT) 14:36:07.358 -> Got time adjustment from NTP! 14:36:12.353 -> epoch time: 1736346972 14:36:12.353 -> UTC Time: Wednesday, January 08 2025 14:36:12 14:36:12.353 -> Local Time: Wednesday, January 08 2025 1…

[image] fairfield87: I have modified the ESP32>Examples>Time>Simple Time example to include a method to regularly synchronise the ESP32 RTC to NTP time. Not necessary, this is already done automatically by the library. As @noiasca mentioned, this is every hour, by default. 15s is too frequent…

According to nayarsystems/posix_tz_db/blob/master/zones.csv "Africa/Abidjan","GMT0" "Africa/Accra","GMT0" "Africa/Addis_Ababa","EAT-3" "Africa/Algiers","CET-1" "Africa/Asmara","EAT-3" "Africa/Bamako","GMT0" "Africa/Bangui","WAT-1" "Africa/Banjul","GMT0" "Africa/Bissau","GMT0" "Africa…

[image] noiasca: the correct timezone definition for Europe/London is Europe/London GMT0BST,M3.5.0/1,M10.5.0 Which @fairfield87 's code has but doesn't use: [image] fairfield87: const char* TZ_UK = "BST0GMT,M3.5.0/M10.5.0"; // Timezone rule for UK including daylight offset rules

[image] noiasca: Europe/London GMT0BST,M3.5.0/1,M10.5.0 Thank you for that. I'll change it when I work up the motivation to rebuild code that's a few years old and from many projects ago. I do remembering Googling a lot, but I don't remember where I got this from, nor how much I changed what…

[image] Dave_Lowther: I do remembering Googling that's my "NTP bare minimum" version: https://werner.rothschopf.net/microcontroller/202103_arduino_esp32_ntp_en.htm

[image] noiasca: as far as I know the default update time is 1h anyway. This has AFAIK been changed to 3 hours. Leo..

[image] fairfield87: configure the TimeZone and daylight savings time information using the method ConfigTzTime(); The timedelay is purely for testing. Longer times of 12 hours would be sufficient. // Modified ESP32 Simple Time Example // To demonstrate how to set the time zone information usi…

Hi noisca The 1, in GMT0BST,M3.5.0/1,M10.5.0 is not required as the default value for daylight saving is 1 hour

ESP32 Get regular updates from NTP

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noiasca January 8, 2025, 4:04pm 2

as far as I know the default update time is 1h anyway.
15 secs is a really overkill. Please modify your example to something more reasonable.

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