[comp.os.msdos.programmer] VGA expansion and some questions...

whoami@unix.cis.pitt.edu (Karol Gieszczykiewicz) (01/03/91)

	Greetings.

	I have several question, some related to this group:

	1) I am thinking of building a processor card for use
	as a speedup for a VGA 3D modeling program* . I would
	like to know if it is feasible to use the 26-pin "expansion"
	edge-connector on most VGA cards for this purpose. (I think
	I have seen some cards that do this...)

	2) How do I program the expantion port? I have simple VGA
	manuals but they do not mention how to get data from/to the
	extra port... Anyone know of an example - anything would be
	nice.

	3) Is there BIOS support for the 26-pin connector? I saw
	nothing to indicate this, but I have been wrong before :-)

	4) And last, does anyone know if I can access the VGA's 
	internal RAM with DMA, copy it to a different card, work
	on that data, and then copy it back? Nothing fancy. 

	Take care.

	P.S. Please use e-mail. I will summarize if there is demand.

	* I would like to add a processor to the VGA card to make
	realtime animation possible - perhaps 30 to 50 frames/sec
	using simple line drawings (no filling in) but at 1024 X 768
	and 4 colors. I am told that this can not be done with just
	the VGA card alone - even in a 33MHz 80386/80387. Anyone?