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From: mcdonald@uxe.cso.uiuc.edu
Newsgroups: comp.unix.xenix
Subject: Re: Writing directly to screen memory o
Message-ID: <47900007@uxe.cso.uiuc.edu>
Date: 10 May 88 18:49:00 GMT
References: <274@gandalf.littlei.UUCP>
Lines: 19
Nf-ID: #R:gandalf.littlei.UUCP:274:uxe.cso.uiuc.edu:47900007:000:989
Nf-From: uxe.cso.uiuc.edu!mcdonald    May 10 13:49:00 1988



>Has anyone ever written directly to the screen memory with UNIX or
>XENIX on a PC?  I know that I probably open /dev/mem and start 
>writing at the ega address space (after probably massaging the
>video controller or whatever).  The UNIX that I am running is

I am also interested in this. It appears that the cheapest way to
get access to a 386 operating system and good C compiler is some flavor
of Unix. I need, however, to be able to write direct to the screen
and use the IO ports on the graphics board to do animation graphics.
There should be some way to get a segment selector to point to the
graphics memory, but one would also need to get IO access to the IO
ports on the graphics card to be able to do anything useful. I looked
in a book about the 386, and it is clear that it can be done, but,
the question is how. Does any flavor of Unix for the 386 allow
graphics access? I know that OS/2 does do so, but only for the 286
mode.

Doug McDonald  (mcdonald@uxe.cso.uiuc.edu)