On Thu, Apr 29, 2021, 10:46 PM yuta <yutr...@gmail.com> wrote: > > I changed "System timer tick period (microseconds)" from 10000 to 1000 > then I got 1.001000 sec in result which is more exact than before. > I'll try Tickless OS configuration if I need later. >
Increasing the tick rate may increase the resolution on the timers but it will also increase overhead and energy usage, so it is not free. This is covered in the wiki article that Alan linked. usleep is still not guaranteed to be the duration, if the system is very busy especially with higher priority tasks running it could be quite delayed, so consider your task priority. This is discussed here: https://pubs.opengroup.org/onlinepubs/009604599/functions/usleep.html --Brennan
