Re: [Gumstix-users] Usleep drv

[Dave H. <dhy...@gm...>]

Hi Dante,

>  I need to measure the time elapsed between some SPI readings+calculations.

>From kernel space or user space?

>  I have been using the usleep module that D. Hylands put up in the Buildroot
>  wiki, and the function it uses to test the performance of the module gives a
>  [seconds].[microseconds] output. Is there a function I can use to measure
>  microseconds?

>From kernel space, one of the timers runs at approx 3.6 MHz. You can
use that timer directly.

>From user space, I believe thatgettimeofday returns the highest
resolution timer. The actual resolution depends on which version of
the kernel is being used.

>From kernel space, the same function is called do_gettimeofday.

-- 
Dave Hylands
Vancouver, BC, Canada
http://www.DaveHylands.com/