Re: interrupt latency

From: yodaiken@fsmlabs.com
Date: Tue Aug 27 2002 - 14:54:01 EST


On Tue, Aug 27, 2002 at 02:01:43PM -0400, Richard B. Johnson wrote:
> This cannot be. A stock kernel-2.4.18, running a 133 MHz AMD-SC520,
> (like a i586) with a 33 MHz bus, handles interrupts off IRQ7 (the lowest
> priority), from the 'printer port' at well over 75,000 per second without
> skipping a beat or missing an edge. This means that latency is at least
> as good as 1/57,000 sec = 0.013 microseconds.

Assuming you mean 75,000 then ...
Thats 0.013 MILLISECONDS which is 13 microseconds and its not likely.
I bet that your data source drops data or looks at some handshake
pins on the parallel connect.

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

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