From: "Tonu Aas" <tonu AT ids DOT ee>
Newsgroups: comp.os.msdos.djgpp
References: <MPG DOT 152d9471aac5b554989689 AT news DOT ntlworld DOT com> <2110-Thu29Mar2001220437+0200-eliz AT is DOT elta DOT co DOT il> <MPG DOT 152ee069d33df48f98968b AT news DOT ntlworld DOT com> <3AC58A8A DOT F1797197 AT is DOT elta DOT co DOT il>
Subject: Re: DJGPP Interrupt programs running under Win98 Console
Date: Mon, 2 Apr 2001 09:39:28 +0300
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To: djgpp AT delorie DOT com
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Reply-To: djgpp AT delorie DOT com

> > I'm still confused - I'd naievely assumed I'd chained onto the one and
> > only hardware timer interrupt in Windows. This interrupt occurs whether
> > my program is in the foreground or background.

> The only way Windows
> can do that is by virtualizing every aspect of the machine's hardware.

And Windows downgrades your chipset also.
You timer chip 8254 becomes trough virtualisation into readonly 8253 !
(You cant reprogram timer into square wave generator and also you cant
read back timer output status(8254 feature)).

Thats bad.