On Monday 09 September 2002 04:01 pm, you wrote:
> On Mon, 09 Sep 2002, anton wilson wrote:
> > unsigned time, time_low, time_high;
> > unsigned mhz = 150000000; // 150 MHz processor
> > __asm rdtsc // Read time stamp to EAX
> > __asm mov time_low, eax
> > __asm mov time_high, edx
> > Sleep (35000); // Sleep for 35 seconds
> > __asm rdtsc
> > __asm sub eax, time_low // Find the difference
> > __asm sub edx, time_high
> >
> > __asm div mhz // Unsigned divide EDX:EAX by mhz
> >
> > __asm mov time, eax
> > printf("Seconds: %u\n", time);
> >
> > What exactly does the div line do?
>
> divides the number of cycles measured by the number of hertz which
> leads to the seconds consumed ,-)
>
I know that's what it does,
but what is the dividend? Is it the 64-bit number created by combining eax
and edx? I don't understand where the dividend on that line is coming from.
And if it is a 64-bit number, how do I change the mull assembly in
do_fast_getttimeoffset to do the same thing?
Anton
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