Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!usc!apple!fox!portal!cup.portal.com!Ordania-DM
From: Ordania-DM@cup.portal.com (Charles K Hughes)
Newsgroups: comp.sys.atari.8bit
Subject: Souping up the Atari cpu...
Message-ID: <24993@cup.portal.com>
Date: 14 Dec 89 02:38:40 GMT
Organization: The Portal System (TM)
Lines: 23


   Ok, I know that millions of devoted atarians out there read USENET 
religiously EVERY day just looking for some interesting articles.  THIS
is one of them. :)

   All you electronic BSers, PHD's (Piled Higher and Deeper :), etc...I 
need your help.  I want to speed up my Atari...doubling the speed would be
fine (3.59MHz) I just want to know how to do it.
   Here is a description of the problem:  
      The atari 8 bit has 3 types of chips in it: 65xx, ram/rom, and 
special purpose chips (antic, gtia, pokey).  All the chips in the atari
can handle an increase in speed (the 6502 and 6520 can be replaced) EXCEPT
the special purpose chips.  What I want to do is steal the a 3.59MHz clock 
from the onboard xtal and direct it to everything except the special purpose
chips.  The antic chip occasionally steals cycles from the cpu in order to 
read directly from ram.  Can this be done?  If so, how?
  [Redesigning the entire computer is not feasible, I just want to make the 
upgrade on my own machine.]
  If this is possible, could it be made switchable (to select 1.79/3.59)?

Thanks
 Charles Hughes
 @cup.portal.com