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Re: No slot clock

Subject: Re: No slot clock
From: "Tom \"Cowgod\" Greene" <cowgod@rockpile.com>
Date: 1997/04/24
Newsgroups: comp.sys.apple2
Organization: INTAC Access Corporation - An Internet Service Provider
References: <5jb0c0$6nl$1@news.vanderbilt.edu> <5jcvgd$rhn@hyperion.triode.net.au> <335bc082.104433632@news.concentric.net> <5jle24$okk@uni.library.ucla.edu>

pubpc1@library.ucla.edu wrote:

> BTW, does anyone know why 9 42256 chips make up a 256K bank in an
> XT while only 8 42256 chips make up 256K in an Apple IIe?
> 

Most likely it is for parity. If a computer uses a parity bit in it's
 memory it uses 9 bits to store one byte. The 9th bit is to help check
for memory errors.

Forgive me if this is not quite understandible, I'm having a hard
time explaining it. :)

----------------------------------------------------------------------
Tom "Cowgod" Greene				http://apple2.base.org
cowgod@rockpile.com				http://cowgod.base.org

References:
- No slot clock
  - From: NO%lesh%SPAM%erjt%HERE@vuse.vanderbilt.edu (Tilghman Lesher)
- Re: No slot clock
  - From: Andrew Roughan <posty@iggy.triode.net.au>
- Re: No slot clock
  - From: wernst@cris.com (Warren "Llama" Ernst)
- Re: No slot clock
  - From: pubpc1@library.ucla.edu

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