Video chipset trials and tribulations

Jan 16 02:43 UTC 1993

I could use some help from anyone who "speaks" Western Digital video
programming -- a.k.a. Paradise video cards.

My notebook PC has a 1Meg video "card" that uses the WD90C20 chipset.
Apparantly, this model is not entirely upward compatible with WD90C00 or
WD90C10 cards.

I've been struggling trying to get this chipset to report clocks correctly,
and to sync properly, in 256-color mode.

The specific application with problems is X386, which is X-Windows for
386 based Unix platforms.  I have to select clocking (dot rate) as well
as both horizontal and vertical sync timing, to drive a stable image.  Hmmm,
2-color doesn't work either, unless I use an EGA driver at 640x480x2, and 
avoid the entire VGA-SVGA capability of my hardware.  I'd rather not do this,
as the 64K EGA video ram severely limits my "virtual screensize" to about
800x600 mono, with a 640x480 screen.  Ick.

I know that it is the video chipset.  The same software and monitor 
used with a PC that had an ET4000 chipset worked flawlessly.
 
I also have problems under MS-DOS with the 640x480x256 windows 3.1 driver.
The old 3.0 driver seems to work. This isn't as critical as the X386
problem.  I really need 1Meg of video ram, and 256 colors.  Help!! 

I have the source to the PVGA1A and WD90C00 driver for X386, but I don't
have the slightest idea what to do to "fit" the WD90C20 to it, as I have
no documentation whatsoever.

I turn to those of you who speak SVGA internals, 'cause I certainly don't.

response 2 of 7:

Jan 22 12:27 UTC 1993

Sigh.  Thanks for trying, anyway.

response 4 of 7:

Jan 30 03:44 UTC 1993

Call WD. The 90C20 is an older chip -- the current ones are the 90C30 and
the 90C31. Sorry I can't help.

response 6 of 7:

Feb 4 23:14 UTC 1993

  If you have Usenet posting access anywhere, post to 
comp.windows.x.i386unix and see if anyone else has had to
deal with this already..