Path: utzoo!mnetor!uunet!mcvax!ukc!mupsy!liv-cs!unpowell
From: unpowell@csvax.liv.ac.uk
Newsgroups: comp.sys.atari.st
Subject: Re: Screen memory format (Correction?)
Message-ID: <530@csvax.liv.ac.uk>
Date: 18 Apr 88 16:21:01 GMT
References: <8803271924.AA18903@ucbvax.Berkeley.EDU> <429@mks.UUCP>
Lines: 25
Organisation: Computer Science CSVAX (VAX1), Liverpool University


In article <429@mks.UUCP>, wheels@mks.UUCP (Gerry Wheeler) writes:
> The illogical method is the one that is used.  In low res mode, you have
> to visualise the memory as sets of four words.  The corresponding bits
> in each of the words are the four bits that specify the entry in the
> palette.  For example, if the words are:
> 
> 	1xxxxxxxxxxxxxxx	$78000
> 	0xxxxxxxxxxxxxxx	$78002
> 	1xxxxxxxxxxxxxxx	$78004
> 	1xxxxxxxxxxxxxxx	$78006
> 
> then the bits of the first pixel are 1011.

The bits of this pixel are, in fact, 1101. ($78000 is the least significant
word, whereas $78006 is the most). So the colour in pallette 1101=13 (dec.) will
be displayed for this pixel.
 
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