Path: utzoo!utgpu!news-server.csri.toronto.edu!bonnie.concordia.ca!thunder.mcrcim.mcgill.edu!snorkelwacker.mit.edu!think.com!sdd.hp.com!uakari.primate.wisc.edu!zaphod.mps.ohio-state.edu!sol.ctr.columbia.edu!lll-winken!uunet!mcsun!hp4nl!phigate!philica!adrie From: adrie@philica.ica.philips.nl (Adrie Koolen) Newsgroups: comp.os.minix Subject: Re: 486 > Sparc (Was:Re: Minix for 486 PCs) Message-ID: <824@philica.ica.philips.nl> Date: 17 Jun 91 10:42:26 GMT References: <56298@nigel.ee.udel.edu> Reply-To: adrie@beitel.ica.philips.nl (Adrie Koolen) Organization: Philips TDS, Innovation Centre Aachen Lines: 87 In article <56298@nigel.ee.udel.edu> EOAHMAD%NTUVAX.BITNET@cunyvm.cuny.edu writes: >NL%"adrie@PHILICA.ICA.PHILIPS.NL" Adrie Koolen wrote >>I think you're comparing apples with oranges. The SparcStations have a frame >>buffer with only one display mode, which is bit-mapped. They're not designed >>for fast text scrolling. I've recently compared the speed of the graphical > >Typing make is faster than going through all the menu routines. Most of the >people that I saw use the X-window systems use them as text based windows. Then you just have to believe me when I say that typing/editing in an 80*25 character XTerm window on a Sun SparcStation is instantenuous. In fact, the speed of the computer really doesn't matter because display actions in such a small window are much faster than my typing. The advantage I have on my Sun is that I can open a lot of those small windows and view/edit several files simultaneously. I know that on a PC, you can do that as well with the proper software and hardware, but my Sun is by no means worse to use than a PC. >>display systems of my color SparcStation and 33MHz 386 PC with super VGA in >>1024*768*256 mode under MS Windows. I looked at display operations like >>refreshing the screen and copying rectangular areas on the screen. The > >Why do you use 256 colour mode when you need only 16 most of the time. You said it yourself: sometimes, I need more colors. Your question seems an acknowledgement of the fact that 256 colors on a SVGA is considerably slower than 16 colors. >My MS windows with 640X480X16 on 386-25 is as fast as the Sparcstation. May I quote from your first message: >Surprisingly, I find that the Sun Sparc Station 1, even without windows, >at 25 Mhz is so slow at screen updates compared to Minix on my 386/25 without >cache with super VGA display. Seems to me that you're not very consistent in your remarks! BTW, without windows, the SparcStation uses a very big bit-mapped screen (1MB) with very big letters to emulate a 80*34 terminal. Character IO is done via Forth routines which are stored in the boot PROM. Of course this is slow. Almost nobody uses the `console' mode on a SparcStation. Use a windowing system like OpenWindows or XWindows; they have direct access to the frame- buffer and thus are much faster. >There is no point to use 1024X768X256 mode because my software does not >support it. The only thing I can conclude from that is that that's the fault of your software. But if you're ever able to get software that supports this mode (almost every SVGA card comes with MS windows 3 driver for all high res modes), please take a look and you'll find that screen IO is slow. >The AT-bus can go at 16Mbit/s. The 32 bit EISA can do 33Mbyte/s. It is not >the AT bus, it is the VRAM. You need dual ported VRAM. Why don't you try >VGA display cards with cache from Trident. First, 16Mbit/s is 2MB/s and that means max 1MB/s scrolling, unless you use the special tricks in VGA plane modes. That's not fast. Second, I've no PC at home, only one at work. My boss won't pay for SVGA cards just to test the speed of them. Finally, are the Trident cards really that much faster than ET4000 cards in 256 color graphics mode? Can you give examples of how fast you can move a screen rectangle to another part of the screen in 256 color mode? I'm curious! >>BTW. Framebuffer access on the SparcStation IPC takes some 7 cycles, so you >>can access 4 pixels (32 bits) more than 3 times per us. > >Does it have 4 bit mode? No, the color frame buffer of the SparcStation (cg3) doesn't know different modes. Only one: 1152*900*256. >For PCB design I can use ORCAD PCB. For PAL programming I use ABEL. For PGA >design I use XILINK. For networking connection I use Dec terminal emulator. > For software simulation I may use Turbo C++. All running on MSDOS on > IBM PC. With 486-33Mhz and 600Mbyte, I have no need for Sun Workstation, >at least for the moment and I notice that a lot of CAD software can be used >on the IBM PC even for the most sophisticated ones and they are cheaper. Let me quote from your first article one more time: >Minix is not only for learning >but also for serious users who wants work done quickly. You just indicated a reason why serious users don't use Minix: (almost) all serious PC programs run under DOS, not Minix. I've nothing against Minix, I just observe and take note. Adrie Koolen (adrie@ica.philips.nl) Philips Innovations Center Aachen