Re: Delay in milliseconds and need info abt Multimedia timers

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Mahesh BS wrote:
Thankyou for the reply.

Sorry. I was looking out for delay in microseconds.
Do you have any idea?

Read my response again.

Tom


Regards,
Mahesh

"Tom Widmer [VC++ MVP]" <tom_usenet@xxxxxxxxxxx> wrote in message
news:OFvTYh3mGHA.1204@xxxxxxxxxxxxxxxxxxxxxxx

Mahesh BS wrote:

Hello,

I am trying to develop application which needs some delay to be
introduced. Here I need to introduce a delay of few micro seconds. Using
Multimedia timers I could get a lowest delay of up to 1 ms.

1) Can anybody help me in knowing how can we achieve a delay of few
millseconds on VC++.

Which is it, microseconds or milliseconds?


2) Does anybody have an idea about the accuracy of the multimedia

timers.

If you call timeBeginPeriod(1), you get 1ms roughly (wakeups on the
whole will be between 0 and 1ms late), and that's the best blocking wait
accuracy available on Win32.

If you need a delay of a few microseconds, a non-blocking busy wait
using QueryPerformanceCounter is the way to go, making sure your process
priority class is set to REALTIME_PRIORITY_CLASS.

Note that it is hard to guarantee any particular accuracy on Windows
since it isn't a realtime system, but you should be able to get good
"average" scheduling.

Tom



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