How set epoch on ESP32 and Arduino IDE to update the timedate without external RTC and Wifi?

[thoraz]

On my ESP32 I want to have information about actual time without Wifi connection or an external RTC chip. I started with this simple code

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time_t now;
struct tm* timeinfo;

void Check_Time(void) {
  time(&now);
  timeinfo = localtime(&now);
  Serial.println(timeinfo);
}

void setup() {
  Serial.begin(115200);
}

void loop() {
  Check_Time();
  delay(1000);
}

It works since the output is

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Thu Jan  1 00:07:57 1970
Thu Jan  1 00:07:58 1970
Thu Jan  1 00:07:59 1970
Thu Jan  1 00:08:00 1970
...

and naturally it starts from 1 Jan 1970. Now I want to update this time to the actual one but I haven't found a direct solution. I know that I could convert a date to a

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time_t

data with the

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mktime

function (is it right?) but how I can pass it to the system? How I should manage this problem?

[chegewara]

https://github.com/espressif/esp-idf/tr ... em/console

If you want to use only internal RTC you have to remember it has a huge drift.

[lbernstone]

https://github.com/lbernstone/ESP32_settimeofday