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From: rsbx@cbmvax.commodore.com (Raymond S. Brand)
Newsgroups: comp.sys.amiga.tech
Subject: Re: Accessing the Chips directly
Message-ID: <15667@cbmvax.commodore.com>
Date: 7 Nov 90 14:22:20 GMT
References: <1220@iceman.jcu.oz>
Organization: Commodore-Amiga Inc, West Chester, PA
Lines: 29

In article <1220@iceman.jcu.oz>, cpca@iceman.jcu.oz (C Adams) writes:
> I was wondering whether C= supported directly writing to the chips
> registers.  I know you would have to do a Forbid()/Permit() and
> make sure blitter DMA was finished etc. to be multitasking friendly,

No, you would have to get control of the resource in system-software
compatible way. (Hint: see OnwBlitter)

> but does C= state that any new chip set will be compatible with
> the old one.

No.

> ie. would my program break on an Amiga 4000 if I wrote to the 
> chips for speed.

Count on it.

> Colin Adams
> Email: cpca@marlin.jcu.edu.au

					rsbx

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