Precise timings ?

Adriaan Renting renting at
Wed Aug 31 09:28:16 CEST 2005

One of the limits of at least IBM compatible PC's is that in general they are not more accurate as about 1/64 th of a second if I recall correctly. I think this is the default tick size of the BIOS clock. Next to that the
BIOS clock itself doesn't need to be very accurate, I can easily drift like an hour a year.
Oh, and on top of that: If you are in a multi taksing operating system this complicates matters even further. Finally there's interrupts, as other posters pointed out.

This explains it very well:

There was a thread with the same question 'time.clock() problem under linux (precision=0.01s)' about a month ago.
I think it had some suggestion of using a soundcard sampling rate to get an accurate clock. I think that without an external calibrated device, you're not going to get any real accurate timing, precission isn't the same as accuracy.


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