Message-ID: <3360905B.5182@pobox.oleane.com>
Date: Fri, 25 Apr 1997 13:07:07 +0200
From: Francois Charton <deef AT pobox DOT oleane DOT com>
Organization: CCMSA
MIME-Version: 1.0
To: Roger Noss <noss AT pupk DOT unibe DOT ch>
CC: djgpp AT delorie DOT com
Subject: Re: Changing the color palette
References: <1 DOT 5 DOT 4 DOT 32 DOT 19970425091422 DOT 002f4204 AT ubeclu DOT unibe DOT ch>
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Roger Noss changed a color in the palette by writing to 0x3c8 and 0x3c9, 
and asked: 
> 
> Does anyone know when the palette is changed: instantaneously or on the next
> vertical retrace?
>

Change is instantaneous, that is, the graphics card immediately proceeds 
to changing the colour (it may take some time on slow cards though).

With many cards, this can be seen by "snow" appearing on the screen when 
you change many palette entries in a row... to avoid this, vertical 
retrace synchronisation is often desirable.

Hope this helps
Francois