From: Schuster <Schuster AT eev DOT e-technik DOT uni-erlangen DOT de>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Interrupts Maximum Rate
Date: Thu, 10 Apr 1997 08:04:33 -0700
Organization: Lehrstuhl fuer Elektrische Energieversorgung
Lines: 31
Message-ID: <334D0181.3D05@eev.e-technik.uni-erlangen.de>
References: <Pine DOT SUN DOT 3 DOT 95 DOT 970406144445 DOT 11066A-100000 AT rainbow> <Pine DOT SGI DOT 3 DOT 91 DOT 970407142951 DOT 17332A-100000 AT atmosp DOT physics DOT utoronto DOT ca> <334A5E67 DOT 2E34 AT eev DOT e-technik DOT uni-erlangen DOT de> <Pine DOT SGI DOT 3 DOT 91 DOT 970409112749 DOT 17572A-100000 AT atmosp DOT physics DOT utoronto DOT ca>
NNTP-Posting-Host: eev6.e-technik.uni-erlangen.de
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: 7bit
To: djgpp AT delorie DOT com
DJ-Gateway: from newsgroup comp.os.msdos.djgpp

Peter Berdeklis wrote:
> The FAQ suggests that anything more than 10Khz might need a RM handler as
> well.  However, if you've got a P90 then the extra clock cycles probably
> aren't a big deal.

I've made a test:
Envoking a Hardware-interrupt by a small timing - circuit in the ISA
Bus.
The Interrupt PM handler just increments a counter, after a minute stops 
and gives out the calculated frequency = counter/60sec.
The frequency of the circuit is variable, and is 
additionally measured, so the calculated frequency can be prooved.

Here the results:

P120 - Triton I chipset (Intel): 58 kHz
486 DX50 (AMD): 35 kHZ

Additional, if I do 12 imports (0 WS) in the Handler, the result is:

P120 - Triton I chipset (Intel): 40 kHz
486 DX50 (AMD): 22 kHZ

... Just in case, somebody wants to know.
(Perhaps an update in the FAQ, Eli?)
-- 
**********************************************
Michael Schuster
E-mail: Schuster AT eev DOT e-technik DOT uni-erlangen DOT de
Lehrstuhl fuer Elektrische Energieversorgung
http://www.eev.e-technik.uni-erlangen.de/