Some Harvest Moon games do not show the time passing every second and might do it in intervals of 10 or 15.
You can set the time update in the UI in multiples of 10/15 minutes by adding an if statement that checks if the minutes value can be divided by the number in the ClockUpdate function in UIManager. Simply add this below the “int minutes = timestamp.minute; ” line:
if (minutes % 15 != 0) return;
This should stop the rest of the function from executing until 15 minutes have gone by.