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From: mg20+@andrew.cmu.edu (Michael Paul Greelish)
Newsgroups: comp.arch,rec.arts.sf-lovers,alt.cyberpunk
Subject: Re: Count Zero Interrupt
Message-ID: <4bC2VW600VIE094FUA@andrew.cmu.edu>
Date: 7 Nov 90 15:29:38 GMT
References: <1427@carol.fwi.uva.nl>
Organization: Class of '92, Carnegie Mellon, Pittsburgh, PA
Lines: 30
In-Reply-To: <1427@carol.fwi.uva.nl>

Well, I ain't no machine-language hacker, in point of fact I haven't
programmed in *ANY* language in about two years, but:

Count Zero Interrupt:

I believe this command exists in at least the 6502 microprocessor's
vocabulary (I grew up with a 6502 machine, but I programmed it in BASIC
(please, no cheap shots)).

To understand what this is, you must know what is a(n):

interrupt: a break in normal program flow, either deliberate or
accidental (I think)

counter: also known as a register. It's simply a single-byte memory
space containing a number 0-255. (On a 6502, at least.)

decrement: actually, "reset" would be a better word here

So, a count zero interrupt could be defined as:

If there is an interrupt, reset the counter (register) to zero.

______________________________________________________________
|\    /|
|  \/  |  ike Greelish
Carnegie-Mellon U. undergrad
quote: "CMU is as close to artificial reality as you can get in 1990."
stupid disclaimer: My opinions are dictated to me by a 23 year old 
telepathic Chilean aardvark living in my closet.