Message-ID: <BDD73AE8AEE3EF438E07420C2600E9F65C913E@qtiexch0.qgraph.com>
From: "Sisco, Michael" <mdsisco AT qtiworld DOT com>
To: "Djgpp (E-mail)" <djgpp AT delorie DOT com>
Subject: Fw: uclock() within an interrupt handler
Date: Fri, 13 Sep 2002 09:31:27 -0500
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Reply-To: djgpp AT delorie DOT com

Has anyone ever tried calling uclock() from inside an interrupt handler?

I have an interrupt handler which (among other things) handles an interrupt
generated by an encoder used to calculate the speed of a running printing
press. In order to calculate this speed with any significant accruacy, I
need the timing resolution of the uclock() function. However, uclock()
appears to be less than accurate when called within my handler. I have timed
the frequency of our interrupt handler with an oscilloscope and found it to
be repeatable to within 0.1%, but the timings I'm calculating using uclock()
occasionally make very wild fluctuations.

Any suggestions?