Re: More accurate Timerevent

On Tue, 21 Nov 2006 21:22:37 GMT, Dirk Claessens <No@xxxxxxxxxxx>
wrote:

On 2006-11-20, Gert Baars (62.194.53.8) wrote in
message <73d6e$4561b3d6$3ec23508$15065@xxxxxxxxxxxxxx>


Hello,

Thank you for info. I'd like to try timeSetEvent but Delphi 7 doesn't
recognize it and helpfunction neither. Do I need to add a .dcu at 'uses'? Is
this somehow documented?

Gert,

Don't bother looking for it... it's a waist of time.
You **cannot** generate accurately timed events on a Windows platform.
As others said: you need hardware.


On modern PC's, You are wrong, and the "others" you mention are also
wrong.

Try the following:


GetTickCount() has a resolution of 1 ms, so we would expect to see it's
value incrementing by 1 ms or there about , right?

The value returned does have a resolution of 1 ms. The timer it is
measuring has a precision which is greater (10-15ms depending). You
simply are misunderstanding the behaviour characteristics of *one* of
the clocks available under Windows.

Time measurement, in any environment, is not a simple as most people
perceive.

For more info on time measurement in general, check out the NTP
reference material.

For a good discussion on PC Hardware Timers, Google for VMWare and
Timers.
--
Please remove '_SpamTrap' when replying. You know why :-(

Peter Ingham
Lower Hutt
New Zealand
.

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