From:	sandmann AT clio DOT rice DOT edu (Charles Sandmann)
Message-Id:	<10206100352.AA20367@clio.rice.edu>
Subject:	uclock() on Win2K
To:	djgpp-workers AT delorie DOT com (DJGPP developers)
Date:	Sun, 9 Jun 2002 22:52:29 -0500 (CDT)
X-Mailer:	ELM [version 2.5 PL2]
Mime-Version:	1.0
Reply-To:	djgpp-workers AT delorie DOT com

I did some investigation of uclock() ...

On my Win95 box it doesn't work either - the timer seems to stay on
rate generator (so it's not continuous); there are jumps in the time.

On Win2K; from the start of a timer tic in the bios area to the end of 
that tic I see the timer registers cycle through the msb values 280
times (more than one full cycle of the 256 allowable values).  The 
Win2K timer is running on a different frequency to provide a nice
even 20 cycles per second (or it seems) - it then virtualizes the 
DOS timer tick, but doesn't bother with with timer registers - just
lets us see the native values?

In quick summary, I don't see any way to fix this on Win2K, and it
doesn't seem to be reliable on either Win95 box I tested either.
Document as only reliable under DOS?

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