Thus, these functions will return a value in range Period value is used for all of ticks_ms(), ticks_us(), ticks_cpu() functions To be a power of two, but otherwise may differ from port to port. The values is TICKS_PERIOD = TICKS_MAX + 1. This value is not explicitly exposed,īut we will refer to it as TICKS_MAX to simplify discussion. Returns an increasing millisecond counter with an arbitrary reference point, sleep_us ( us ) ¶ĭelay for given number of microseconds, should be positive or 0 utime. sleep_ms ( ms ) ¶ĭelay for given number of milliseconds, should be positive or 0. Not accept floating-point argument, for compatibility with them use sleep_ms()Īnd sleep_us() functions. Sleep for a fractional number of seconds. Seconds can be a floating-point number to year includes the century (for example 2014).If secs is not provided or None, then the current time from the RTC is used. localtime ( ) ¶Ĭonvert a time expressed in seconds since the Epoch (see above) into an 8-tuple whichĬontains: (year, month, mday, hour, minute, second, weekday, yearday) If actual calendar time is not maintained with a system/MicroPython RTC,įunctions below which require reference to current absolute time mayįunctions ¶ utime. RTC time across hard resets, though some may require setting it again Set manually by a user on each power-up (many boards then maintain.Using networked time protocol (requires setup by a port/user).By a backup battery (which may be an additional, optional component for.May be set using machine.RTC().datetime(tuple) function, and maintained System time depends on machine.RTC() object. ![]() Time is responsibility of OS/RTOS and is done outside of MicroPython, On systems with underlying OS (including some Maintaining actual calendar date/time: This requires a Time Epoch: Unix port uses standard for POSIX systems epoch of Measuring time intervals, and for delays. This is done through a mechanism called "system calls" have a read over this wiki article for further reading: Īt a high level, the ru_utime struct returns the amount of time your program has spent doing actual computation, and the ru_stime struct returns the amount of time your program has been waiting for an answer from the kernel when doing disk access, printing to the screen etc.The utime module provides functions for getting the current time and date, memory page allocation, filesystem read/write, printing things to the screen), it must ask the kernel to do it instead, which has access to all of this. To keep this quick and simple, your user mode cannot see all of memory, it cannot communicate with I/O devices, and can only really do number-crunching. In order to prevent you from smashing all over memory, your system has two "privilege levels", called kernel mode and user mode. This is the total amount of time spent executing in kernel mode, expressed in a timeval structure (seconds plus microseconds). ![]() This is the total amount of time spent executing in user mode, expressed in a timeval structure (seconds plus microseconds). The two sub-structs you are interested in are described as follows: So, Can anybody explain this to me or give some good link where this is explained? But what I see in those structs seems to be completely unrelated: I used a stopwatch to actually see how many time it takes, it took 5.23 secs. I ran a simple program with a for loop that allocates and frees memory continually. What's inside them assume different values, sometime 0, other times 2000 etc. What is unclear to me is what is stored inside the rusage struct - the man page isn't very clear - so I tried to run it with a debugger and directly see what's inside, but Still do not understand it, particularly how the two structs - timeval ru_utime and timeval ru_stime - work. Tried to find something on the web, but nothing but the man page about this function is found. I red the man page, 10 times maybe, and still can't get it. Works in order to calculate the running time of one my program. I'm trying to understand how int getrusage(int who, struct rusage* usage)
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