🚀 go-pugleaf

I believe this may actually be possible.  I was programming SVGA assembly
code a while back, and I do remember reading something about the Tseng Labs
ET4000 chip set (SpeedStar I believe uses these) can map its address space
into higher memory.  I am pretty sure the ET4000 is the only Tseng chip that
claims to do this.  Ahh, here I found the text I read this from:

Excerpt from _Programmer's Guide to the EGA and VGA Cards, Second Edition_
by Richard F. Ferraro:

(page 932)
The [Tseng Lab ET4000] can be configured to access memory in a linear or in a
segmented fashion through the SLS field.  This linear addressing mode forces
all display memory to be continuous. ....  If the SLS Field is 1, this linear
mapping scheme is enabled.  If 0, the standard VGA segmented memory mapping
scheme is enabled.  ....it is possible to place the VGA into high memory where
there is room to place one Megabyte of display memory into a contiguous
address space.  This allows the ET4000 to ignore the bank selection registers.

[text goes into more detail..]

If you have an ET4000, this seems possible according to Ferraro.  I could not
find, however, any mention of exactly what address this linear space shows
up at, or even how to specify it yourself.  I was interested in using this
linear mode, so I called Speedstar.  The person I talked to seemed to not
know the chipset could even do this.  He suggested calling Tseng Labs direct.
If anyone finds out how to do this, or if it is truely possible, please let
me know.

-- 
Jason Lowe      |   //       | Take the Oath.  Watch Ren and Stimpy!
stimpy@uiuc.edu | \X/ Amiga! | "And look, he's beating up on our cheese!"