Frederick Williams wrote:
>
> Ali wrote:
>
> > but less than the resolution of the PC real-time clock;
>
> Was that once 1/55 of a second, and is it still?
Here are the details. The IBM PC used an 8253 providing "ticks" at 18.2
Hz. 1/55 = 0.0181818... so I was close. The 8253 was used in all PCs
compatible with the IBM PC up to 2005, but I have been unable to
determine whether it was used with the same divider (but if they were
truly compatible, they must have). The HPET, ticking at at least 10
MHz, only appeared in 2005, and, in any case cannot be used by XP though
it can be used with Vista and Windows 7. What its fastest ticking rate
is, I don't know. I may look into the matter more tomorrow.
--
When a true genius appears in the world, you may know him by
this sign, that the dunces are all in confederacy against him.
Jonathan Swift: Thoughts on Various Subjects, Moral and Diverting