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From: chucks@pnet51.orb.mn.org (Erik Funkenbusch)
Newsgroups: comp.sys.amiga.advocacy
Subject: Re: Blitter vs. 040 (was: Computer Architecture question
Message-ID: <4987@orbit.cts.com>
Date: 24 May 91 06:25:01 GMT
Sender: news@orbit.cts.com
Organization: People-Net [pnet51], Minneapolis, MN.
Lines: 36

dvljrt@cs.umu.se (Joakim Rosqvist) writes:
>>
>>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.

yes it is, the $dff area is in "psuedo" fast ram area, this area is on the
chip bus. 

>
>
>
>/$DR.HEX$
>
>--------------------------------------------
>Email to:  dvljrt@cs.umu.se
>2 Windows on the screen?  Oh no, not me.  I just Logout & Go.

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