On Tue, Mar 23, 1999 at 12:28:56PM +0100, andrea wrote:
> 
> 
> I got some strange behavieur from my AGA X server on NetBSD.
> 
> If i run it at 640x400 averything works fine, but when i try higher
> resolution like 640x480(!!) i got some weirdness on display.
> It seems that the bitplanes are not alligned so i can see 2 o more images
> slighty shifted one from other with the colors completly broken.
> 
> It's my fault?
> 
> the command line to start the server is:
> /usr/X11R6/X -dev /dev/grf0 -W 640 -H 480 -D 8 :0

This sounds like what you see when the driver switches to A2024 mode. 

Long explanation:

from small to big resolutions the driver goes through (on a ECS machine):

- NTSC plane
- PAL plane
- NTSC interlaced
- PAL interlaced
- A2024 

when you have AGA enabled, and an AGA machine, AGA replaces part of the modes.

Now, as A2024 puts a 2-plane gray image into 5 or 6 NTSC or PAL time frames,
a normal monitor shows about what you described. At least, thats what I
remember from myself using ECS in my youth :-)

Regards,
	-is