Message-ID: <c=GB%a=_%p=Indigo_Active_Vi%l=CRIANLARICH-970423120229Z-458@crianlarich.Indigo>
From: Robert Humphris <r DOT humphris AT indigo-avs DOT com>
To: "'djgpp AT delorie DOT com'" <djgpp AT delorie DOT com>,
        "'tgrand AT canvaslink DOT com'"
	 <tgrand AT canvaslink DOT com>
Subject: RE: Measuring frame rate more often
Date: Wed, 23 Apr 1997 13:02:29 +0100
Encoding: 20 TEXT
Precedence: bulk

Tom 

You could attempt this by using some form of external counter that you
can refer to each time
you flip pages.  How you do this I don't know as I work in embedded
systems that have all manner
of clocks for just this sort of thing.  Does the PC have a microsecond
clock? if so just refer to it
and compare previous times.  if there is no clock, and you think that
the overheads will not be too
great, set an interrupt to occur every so often ( mS ) and count the
number of times that it has occurred
between page flips.  To overcome the overhead of the interrupts you
might want to create a look up table
of logical speeds ranging from the fastest frame rate to that of the
slowest, therefore you will not incur
the time penalty of performing the recalculation each time.

Rob Humphris
>