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#! rnews 2887 bsd Path: euryale.cc.adfa.oz.au!newshost.carno.net.au!harbinger.cc.monash.edu.au!munnari.OZ.AU!news.mel.connect.com.au!news.mel.aone.net.au!imci4!imci5!pull-feed.internetmci.com!newsfeed.internetmci.com!howland.erols.net!EU.net!Norway.EU.net!nntp.uio.no!nntp.uib.no!nntp-bergen.UNINETT.no!nntp-trd.UNINETT.no!news.uni-c.dk!cph-1.news.DK.net!dkuug!dknet!dde.dde.dk!berta.dde.dk!news From: Søren Schmidt <sos@freebsd.org> Newsgroups: comp.unix.bsd.freebsd.misc Subject: Re: Simutaneous mono and vga under FreeBSD... Date: Mon, 16 Sep 1996 09:19:21 +0200 Organization: The FreeBSD Project Lines: 43 Message-ID: <323CFF79.E96@freebsd.org> References: <32388517.BA4@wsg.net> <3238632A.6516@www.play-hookey.com> <51eoiu$6ck@diemos.isdfa.sei-it.com> <323C1975.4FA7@www.play-hookey.com> Reply-To: sos@freebsd.org NNTP-Posting-Host: ssc-pc.dde.dk Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8bit X-Mailer: Mozilla 3.0 (Win95; I) Ken Bigelow wrote: > You weren't running an old Hercules card at any 1024x768 -- they didn't > go that high. He didn't say so... > The basic problem is unchanged: to use two video cards for different > displays at the same time, they cannot overlap in either memory usage or > port addresses, nor in IRQ if they use it (EGA used IRQ2 for a vertical > retrace signal). In case of a (S)VGA and a MDA/HErcules they wont. > Now, if you want the Hercules card to run in text mode (which was the > original stated requirement) it will occupy at least 32K at segment B000 > (in half mode; 64K in full mode). You can't change this, and any VGA > graphics mode can't be allowed to use this memory space. This > tremendously limits the graphics modes and amount of memory they can > access directly. > > I see only one way to avoid the conflict. At least one video card, which > must be the VGA card since the Hercules card can't, must get *all* of > its video specifications via I/O operations to one or more ports, and > not by bank-switching memory into the main processor's memory map. If > you can find such cards that are mutually exclusive in their addressing > and you want to adapt simultaneous drivers for them, you can make the > combination work. However, I strongly suspect it will require two VGA > cards in mutually exclusive modes, not a VGA card and a Hercules card. Hmm, most (S)VGA cards cant map more than 64K at a time into the ISA "hole" anyway, so it will work just fine, ie VGA=a0000-affff MDA=b0000-bffff... However most modern SVGA cards can map in their ENTIRE memory in one linear chunk at some arbitrary high address, and all modern Xservers should use that mode for speed. No problem in having a MDA card also. Ïn fact I have had this setup running for years, so it works fine belive me :), may I suggest you go read a couble of books on the subject before making these claims ?? Søren