Time Start and Stop control using RTC

Mbed OS
1

Is there a trick to set a start time and a stop time within a 24 hour period?

I don’t want to use a timer it must use the RTC incase the system resets.

For instance I want to start at 20:00 hours and stop at 05:00 hours, that means going past midnight.

I’m using this to get the seconds and process it from there, but I’ve got a bit of brain freeze and there has to be a simple solution.

void autoLOCK()
{
  int hour_from, minute_from = 0;
  int seconds_from = 0 ;
  
  int hour_to, minute_to = 0;
  int seconds_to = 0;

  if (sscanf(lockFrom, "%d:%d", &hour_from, &minute_from) >= 2)
  {
    seconds_from = (hour_from * 3600 + minute_from * 60);
  }
  if (sscanf(lockTo, "%d:%d", &hour_to, &minute_to) >= 2)
  {
    seconds_to = (hour_to * 3600 + minute_to * 60);
  }

  Serial.printf("\n\nSeconds from: %d\n", seconds_from);
  Serial.printf("Seconds to:   %d\n", seconds_to);
  Serial.printf("Seconds now:  %d\n", seconds_now);

  lockStatus = 0;

  if (seconds_now >= seconds_from) {
    lockStatus = 1;
    Serial.printf("Lock Status 1:  %d\n", lockStatus);
  }

  if (seconds_from > seconds_to) {
    lockStatus = 1;
    Serial.printf("Lock Status 2:  %d\n", lockStatus);
  }

  if (seconds_now >= seconds_to && seconds_from >= seconds_to) {
    lockStatus = 0;
    Serial.printf("Lock Status 3:  %d\n", lockStatus);
  }

  Serial.printf("Lock Status:  %d\n\n", lockStatus);
  
}

Any help would be appreciated.

2

Hello,
do you know the difftime methode ?
example in my programm to start the measurement at a time in the future !!
time_difference = difftime(mktime(&stopzeit[j]),mktime(&startzeit[j]));

Bernd from germnay, sorry for my bad english!