Jared Putnam wrote: > VGA video memory is arranged into four 64k banks, called planes. When > you read from video memory, (depending on the read mode) the card only > gives you one value, it latches data on every active plane. There's a > four-bit bitmask that determines this. When it writes memory, it > writes from the latches to every active plane. Most modes just leave > the latches on one setting; I think only Mode X lets you take advantage > of this, though. > > >
..... >> Is the 80x25 screen laid out as a linear array of 2000 16-bit words? >> > > Yes, but there is more than one screen, and you can switch between > them. > > > > Also, one of the memory banks (plane 2 IIRC) contains the font definition for text modes. Patrick M _______________________________________________ Open-graphics mailing list [email protected] http://lists.duskglow.com/mailman/listinfo/open-graphics List service provided by Duskglow Consulting, LLC (www.duskglow.com)
