ISTR there were a few DOS-only video cards that had VGA outputs, but only did text mode for point of sale applications. I never used any of these myself, though...
Warner On Thu, Mar 25, 2021 at 1:46 AM John Ames <commodorej...@gmail.com> wrote: > Hah, wow. > > On 3/25/21, Warner Losh <i...@bsdimp.com> wrote: > > On Thu, Mar 25, 2021 at 1:01 AM John Ames via cctech > > <cct...@classiccmp.org> > > wrote: > > > >> Huh - wacky. Still pretty curious how it works just on a basic "how > >> the hey does the framebuffer even function" level, but that's > >> certainly interesting. Does make me feel less guilty about planning to > >> cannibalize it for a homebrew project later, though! > >> > > > > It's a text mode, which generates the screen image using rasterized fonts > > from the text + attributes stored in video memory. > > > > There is no frame buffer. With that little RAM it can support the text > > modes easily enough, but none of the graphics modes. > > > > Warner > > > > > >> On 3/24/21, Camiel Vanderhoeven <camiel.vanderhoe...@vmssoftware.com> > >> wrote: > >> > It's neither X nor ethernet. These worked with a special controller > >> > card > >> > that had 4 RJ45 connectors. That allowed four users to share a single > >> > Windows NT system. > >> > ________________________________ > >> > From: cctech <cctech-boun...@classiccmp.org> on behalf of John Ames > via > >> > cctech <cct...@classiccmp.org> > >> > Sent: Thursday, March 25, 2021 4:41 AM > >> > To: cctalk <cctalk@classiccmp.org>; cctech <cct...@classiccmp.org> > >> > Subject: MaxSpeed VGA MaxStation > >> > > >> > So, some months ago, I was in an electronics surplus store and picked > >> > up what was obviously an X terminal - tiny metal slab with a VGA > >> > connector, serial & parallel, AT keyboard, and RJ45 "communication" > >> > port. I got it bare, without the external PSU that would've gone with > >> > it, and I've since been unable to determine just what the heck I'm > >> > supposed to feed this thing. It's a standard barrel jack, but there's > >> > no markings on the case or the PCB to give any clue as to what > >> > voltage/amperage or polarity it expects, and Google has been no help > >> > at all. Does anyone have any recollection of these things? Any idea > >> > what they want for juice? > >> > > >> > To throw an extra mysterious wrinkle into this, when I popped open the > >> > case to get a look at the PCB, I found that, apart from the CPU, DART, > >> > and ROM, the only non-glue ICs on the board were an 8K SRAM and a > >> > W82C476 RAMDAC - but 8K isn't even remotely enough for a VGA screen, > >> > not even a monochrome one at VGA resolution! Am I missing something on > >> > how these things operated? Given this, my only guess would be some > >> > kind of insane networked-framebuffer scheme where the host would blast > >> > video data in on the fly, but there's no way this was even 100Mbps > >> > Ethernet, and 10Mbps isn't nearly fast enough to transfer 150KB at > >> > 60FPS, and there's no memory to buffer it for a slower refresh. What > >> > in the heck is going on here? > >> > > >> > This e-mail (including any attachments) may contain privileged, > >> > confidential, proprietary, private, copyrighted, or other legally > >> protected > >> > information. The information is intended to be for the use of the > >> individual > >> > or entity designated above. If you are not the intended recipient > (even > >> if > >> > the e-mail address above is yours), please notify us by return e-mail > >> > immediately, and delete the message and any attachments. Any > >> > disclosure, > >> > reproduction, distribution or other use of this message or any > >> attachments > >> > by an individual or entity other than the intended recipient is > >> prohibited. > >> > > >> > > >