Re: interrupt latency

yodaiken@fsmlabs.com
Wed, 28 Aug 2002 07:53:19 -0600


On Wed, Aug 28, 2002 at 08:18:25AM -0400, Richard B. Johnson wrote:
> No, no, no. There is no such port read that takes 18 microseconds, even
> on old '386 machines with real ISR slots. A port read on those took
> almost exactly 300 nanoseconds and, in fact, was the limiting factor
> for the programmed I/O devices on the ISA bus.

Amazing how they can do that with a bus clock that is much slower -)

-- 
---------------------------------------------------------
Victor Yodaiken 
Finite State Machine Labs: The RTLinux Company.
 www.fsmlabs.com  www.rtlinux.com

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