viking@iuvax.UUCP (Jon W. Backstrom) (12/11/87)
I can't help thinking what a wonderful machine my Mac II is but how much better it could be if Apple would stop insisting on doing *everything* in software. For the cost of a few DMA chips (what? $0.35 each?) the NuBus could be made to operate in burst mode (like it should), the 68020 could spend more time working and less time pulling bytes of the hard disk, and who knows what else. All this seems to harken back to the days of the Apple II and the clever ways Woz was able to reduce the chip count by using software drivers...(Hey! Let's *write* a disk controller!). That was fine for a machine at that time and the early market appreciated the reduced costs associated with such techniques. The Mac II is probably going to suffer in the workstation market (next to 80386, Apollos, and Suns) unless it can operate faster, however. As a single user machine, I guess none of this really matters much, but two things seem to need addressing: 1) DMA disk access seems to be a needed feature. Does A/UX slow down when it has to swap memory with 5 users, for instance? With the CPU being tied up all the time, speed is bound to suffer. 2) Screen I/O is also managed by the CPU. I dream of the day that Apple or someone (RasterOps?) develops a video card with a graphics co-processor. This is made more difficult by the need to run the quickdraw routines, but maybe somebody can do it! (Apple, are you listening?) Perhaps the use of the NuBus will allow someone to offer a videocard with both a graphics co-processor and a DMA SCSI port....naw, I'm reaching here, I know. But the idea is a good one. I'm definitely not a hardware type, but I really want to see Apple go places. My Mac II is great but I'm hoping to see some of these things develop in the coming year....and maybe Apple will 'do it right' on the 68030 machine for '89. Responses welcome...does anyone have multiuser A/UX experience vs 80386 XENIX? Does the lack of a DMA disk controller really matter? ------------------------------------------------------------------------------- | Jon W. Backstrom "Yah sure...we gonna have fun, you bet!" | | Computer Science Department | | Indiana University UUCP: {ihnp4,pyramid,rutgers}!iuvax!viking | | Lindley Hall 101 ARPA: viking@iuvax.cs.indiana.edu | | Bloomington, IN 47405 | | "The world has arrived at an age of cheap | | (812) 335-2849 (Office) complex devices of great reliability; and | | (812) 336-3660 (Home) something is bound to come of it." | | - Vannevar Bush (1945) | -------------------------------------------------------------------------------
dudek@utai.UUCP (Gregory Dudek) (12/12/87)
In article <5094@iuvax.UUCP> viking@iuvax.UUCP (Jon W. Backstrom) writes: > >2) Screen I/O is also managed by the CPU. I dream of the day that Apple or > someone (RasterOps?) develops a video card with a graphics co-processor. > This is made more difficult by the need to run the quickdraw routines, but > maybe somebody can do it! (Apple, are you listening?) > I believe I've read that a graphics co-processor card (using the TI chip??) should be available within the next 6 months or so. I thought I saw it in a recent Macintosh Today. BTW, I think MacIntosh Today is being very even handed by publishing articles critical of Mac architecture as well as positive stuff. I was really getting sick of the lopsided hype-boosterism typical of so many magazines (like MacWorld). Gregory Dudek -- Dept. of Computer Science (vision group) University of Toronto Usenet: {linus, ihnp4, allegra, decvax, floyd}!utcsri!dudek CSNET: dudek@ai.toronto.edu DELPHI: GDUDEK
gillies@uiucdcsp.cs.uiuc.edu (12/12/87)
Here are some (possible) reasons why you won't see sophisticated DMA
devices or more distributed (outboard graphics) processing on an Apple
PC in the near future:
(1) Apple wants all its peripherals to work with all its computers.
This vastly simplifies marketing for Apple's peripherals. Apple is
moving even farther in this direction, by standardizing the ADB bus,
therefore standardizing keyboard, mouse, and graphics tablet
interfaces. Apple has settled on SCSI so that all its disks will be
hardware interchangeable. So when you sell (or junk) that Macintosh
128 and buy a Mac II, you don't have to throw away that disk drive OR
modem.
(2) Apple does everything in software, possibly because of a holdover
philosophy from Xerox. Xerox does everyhing in software--microcode!
There are very good reasons for this, especially if you're trying to
do a state-of-the-art product. When you release a product, if there's
a serious bug, you can *ALWAYS* provide a software patch (unless the
bug is in the early part of system startup, like the Mac II Nubus 1Mb
bug). Then, at worst, you can provide new ROMS. Bugs in software are:
(1) Easier to diagnose & fix
(2) Faster to fix (replace a ROM or release new system/finder)
(3) Therefore, Cheaper to fix.
Why do you think CRAY Computer corp *REFUSES* to design
state-of-the-art supercomputers in custom or unproven circuit
technologies? When you try to do a state-of-the-art system, it is
important to have some stable ground to stand on.
Don Gillies {ihnp4!uiucdcs!gillies} U of Illinois
{gillies@p.cs.uiuc.edu}daveh@cbmvax.UUCP (Dave Haynie) (12/15/87)
in article <76000065@uiucdcsp>, gillies@uiucdcsp.cs.uiuc.edu says: > Nf-ID: #R:iuvax.UUCP:5094:uiucdcsp:76000065:000:1583 > > (1) Apple wants all its peripherals to work with all its computers. > .... Apple has settled on SCSI so that all its disks will be > hardware interchangeable. So when you sell (or junk) that Macintosh > 128 and buy a Mac II, you don't have to throw away that disk drive OR > modem. No good. We use Mac compatible hard disk drives on Amigas with DMA driven SCSI all the time. SCSI is a reasonably standard interface, and Mac compatible SCSI a more standard subset of it (at least these days). SCSI tells you only how data gets off the hard disk drive, not how that data ultimately winds up in the computer's memory. The good news is that is Apple ever decided to give you a DMA driven SCSI port, all the currently existing SCSI peripherals would work with it, only faster. > Don Gillies {ihnp4!uiucdcs!gillies} U of Illinois > {gillies@p.cs.uiuc.edu} -- Dave Haynie Commodore-Amiga Usenet: {ihnp4|uunet|rutgers}!cbmvax!daveh "The B2000 Guy" PLINK : D-DAVE H BIX : hazy "I can't relax, 'cause I'm a Boinger!"