> I know that this would simply be accomplished no problem with X-Window
> System, however I have had some difficulties with the Amiga port of X11..
> and would now like to find out how to use the /dev/grf* devices and
> directly access the display chips.

 This is a "NO NO", a "You dont want that" issue :-)

 You can of course do so, have a look at my trial sources to display
a PPM-picture directly in the graphic board. They are in my old cirrus
archive called something like cirrus3.tar.gz on ftp.uni-regensburg.de

 This is of course Amiga-only.

-- 
Markus Illenseer