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From: dvljrt@cs.umu.se (Joakim Rosqvist)
Newsgroups: comp.sys.amiga.advocacy
Subject: Re: Blitter vs. 040 (was: Computer Architecture question
Message-ID: <1991May23.075950.4177@cs.umu.se>
Date: 23 May 91 07:59:50 GMT
References: <4954@orbit.cts.com>
Sender: news@cs.umu.se (News Administrator)
Organization: Dep. of Info.Proc, Umea Univ., Sweden
Lines: 22

>
>let me say this loudly!
>
>THERE IS LITTLE REASON FOR THE CPU TO ACCESS THE SAME BUS AS THE BLITTER!
>
>there, most everything the cpu does (executing programs) is done in fast
>memory.  fast memory is on a seperate bus than chip memory. therefore having 2
>busses with 2 seperate processors on them means there should be little bus
>contention.  the only time the cpu NEEDS to access chip memory is to program
>the blitter, and that's only for a few cycles.  
>

It doesn't need to access chip ram even then. The blitter-control registers
are in the $dff area, not in chip ram.



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