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From: Andris Pavenis <pavenis AT latnet DOT lv>
To: djgpp AT delorie DOT com
Subject: Re: Troubles with hard interrupts aand HDD
Date: Thu, 10 Jun 2004 16:15:35 +0300
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On Thursday 10 June 2004 13:32, turomas wrote:
> I am developing a CNC. I use a hard interrupt every 500 micro seconds. I
> have used Irq9 and Irq0 too. It works fine but when I use HDD the latency
> gets back to 2,5 ms. Can somebody help me.

Perhaps HDD interrupt handling could take rather much time in DOS or somewhere 
interrupts are getting masked for up to 2.5 ms. Also switching between real 
and protected mode requires time. 

I myself would try to use some real time operating system for such task (see 
for example http://www.rtai.org).

Andris