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From: kaba@wintermute.north.de (Kai Bartels)
Newsgroups: comp.sys.amiga.programmer,comp.sys.amiga.hardware,adsp.sw,adsp.hw
Subject: Re: 68040 Compatibility Warning
Message-ID: <1991Jun1.175626.3234@wintermute.north.de>
Date: 1 Jun 91 15:56:26 GMT
References: <22049@cbmvax.commodore.com>
Organization: nothing (absolutely nothing) is organized here!
Lines: 17

mks@cbmvax.commodore.com (Michael Sinz) writes:
>CopyBack. CopyBack means that when a program writes data to
>memory, it goes into the cache but *not* into the physical RAM.
>That means that if something was to read that RAM and it did not
>go through the data cache on the 68040, it will see old data.
>The two main examples of this are DMA devices and the instruction
>reading of the CPU itself.  This means that even if the
Another important case where that mode can be deadly is in a multi-processor
machine. Has Motorola or C= taken any precautions in this direction. It'd be
really nice to run ADos2.0 or SVR4 on two or three processors!

Kai

-- 
"I'm beat, I'm torn, Shattered and tossed and worn, Too shocking to see" <CS>
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