Monochrome modes have 1 bit per pixel... no byte alignment here!
4 bit standard was introduced when video memory was scarce, and
cards had only 256k...

Earl Truss wrote:
>
> ----------
> > From: David Gillett <[log in to unmask]>
> > Subject: Re: [PCBUILD] only 16 colors with S3 trio 64+
> > Date: Monday, March 22, 1999 8:25 PM
> >
> > On 22 Mar 99, at 15:08, Earl Truss wrote:
> >
> > > Colors                        Number of bytes
> > > 16                               1
> >
> >   .5, actually.  A vanilla VGA can do 16 colours at 640x480 resolution
> > with only 256KB of installed video RAM (and some really gross interface
> > programming, which is why you want the driver to take care of the
> > details), and everybody emulates this as a "lowest common denominator".
> >
> But does it really only use 1/2 byte for each pixel?  I would think this
> would be pretty horrendous for the card to handle since most hardware works
> on byte boundaries rather than trying to work on four-bit boundaries.
> Maybe that's what you are talking about when you mention "really gross
> interface programming"?
>
> I thought it more likely that the card is really running at EGA/VGA
> resolution of 640x320 which can be done in 256K using a full byte for each
> pixel.  Once upon a time, 640x480 and anything above that was considered
> "super VGA" resolution.
>
>                          PCBUILD's List Owner's:
>                       Bob Wright<[log in to unmask]>
>                         Drew Dunn<[log in to unmask]>

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