Introduction - If you have any usage issues, please Google them yourself
put a year, month, day and hour, minute and second time for a change based on at 0:00 a.m. on January 1, 1970 0 0 seconds seconds; Or one based at 12:00 a.m. on January 1, 1970 0 0 seconds concurrently converted to a year, month, day and hour- and second time. Consider the source of the impact of a leap year. In embedded development, in the absence of the RTC, such a conversion is very useful, it is easier to maintain a system of time.