jm7e+@andrew.cmu.edu (Jeremy G. Mereness) (02/17/89)
My //gs system came with Unidisk3.5 instead of the Apple3.5 I know that the Unidisk is not capable of 2:1 interleave and thus some software packages will not run with the device. If I sell it, will it work on a Macintosh? And how good are the Laser 3.5 drives? Are they compatible with the Apple 3.5 drives or do they have similar problems with the Unidisk? jerry jm7e+@andrew.cmu.edu (arpa) r746jm7e@cmccvb (bitnet)
keith@Apple.COM (Keith Rollin) (02/17/89)
In article <YXynj3y00VoH4BzH8e@andrew.cmu.edu> jm7e+@andrew.cmu.edu (Jeremy G. Mereness) writes: > > >My //gs system came with Unidisk3.5 instead of the Apple3.5 > >I know that the Unidisk is not capable of 2:1 interleave and thus >some software packages will not run with the device. As a girlfriend of mine used to say, "Wait...What?" [dazed uncomprehending look] What software packages won't work on a drive that can't efficiently read a 2:1 interleave? Stuff with copy-protection? Otherwise, it shouldn't matter. >If I sell it, will it work on a Macintosh? Nope. There are smarts in the Unidisk that prevent it from working on a Mac. I also think that there is a small wiring difference, but I don't know what it could be. ------------------------------------------------------------------------------ Keith Rollin --- Apple Computer, Inc. --- Developer Technical Support INTERNET: keith@apple.com UUCP: {decwrl, hoptoad, nsc, sun, amdahl}!apple!keith "Argue for your Apple, and sure enough, it's yours" - Keith Rollin, Contusions
delton@pro-carolina.cts.com (Don Elton) (02/17/89)
Jerry Mereness writes: >I know that the Unidisk is not capable of 2:1 interleave and thus some >software packages will not run with the device. Nope, you thought you knew this. There are no software programs that detect the interleave and really care about it (at least no applications). If a disk is formatted for a 2:1 interleave and run on a Unidisk the disk I/O will just be a little slower since 2:1 isn't optimal for that disk drive. The application never knows the difference though since Interleave is handled below the level of ProDOS or GS/OS MLI calls. UUCP: [ sdcsvax nosc ] !crash!pro-carolina!delton ARPA: crash!pro-carolina!delton@nosc.mil INET: delton@pro-carolina.cts.com Pro-Carolina: 803-776-3936 (300-2400 baud, login as 'register') US Mail: 3207 Berkeley Forest Drive, Columbia, SC 29209-4111
JDA@NIHCU.BITNET (Doug Ashbrook) (02/17/89)
> My //gs system came with Unidisk3.5 instead of the Apple3.5 > > I know that the Unidisk is not capable of 2:1 interleave and thus > some software packages will not run with the device. From everything that I have read, the Unidisk *IS* capable of reading and writing to disks formatted with a 2:1 interleave. It is just that the access will be considerably slower than if the disk was formatted with a 4:1 interleave. ------------------------------------------------------------------- J. Douglas Ashbrook (301) 496-5181 BITNET: JDA@NIHCU ARPA: jda%nihcu.bitnet@cunyvm.cuny.edu National Institutes of Health, Computer Center, Bethesda, MD 20892
dcw@athena.mit.edu (David C. Whitney) (02/17/89)
In article <25945@apple.Apple.COM> keith@Apple.COM (Keith Rollin) writes: >In article <YXynj3y00VoH4BzH8e@andrew.cmu.edu> jm7e+@andrew.cmu.edu (Jeremy G. Mereness) writes: >> >> >>My //gs system came with Unidisk3.5 instead of the Apple3.5 >> >>If I sell it, will it work on a Macintosh? > >Nope. There are smarts in the Unidisk that prevent it from working on a Mac. I >also think that there is a small wiring difference, but I don't know what it >could be. To clarify: it *will* work on a mac as long as you open the drive up and perform some brain surgery. It's a pretty simple job - just a matter of pulling a couple of connectors and replacing another. IT WILL VOID YOUR WARRANTY. I know this works as I've done it myself, and the drive has been happily driving on my dad's mac for about 3 years. Dave Whitney A junior in Computer Science at MIT dcw@athena.mit.edu ...!bloom-beacon!athena.mit.edu!dcw dcw@goldilocks.mit.edu I wrote Z-Link. Send me bug reports. I use a //GS. Send me Tech Info. "This is MIT. Collect and 3rd party calls will not be accepted at this number."
shawn@pnet51.cts.com (Shawn Stanley) (02/17/89)
jm7e+@andrew.cmu.edu (Jeremy G. Mereness) writes: >My //gs system came with Unidisk3.5 instead of the Apple3.5 > >I know that the Unidisk is not capable of 2:1 interleave and thus >some software packages will not run with the device. With the 2:1 interleave, it will actually take much longer for the Unidisk to retrieve the sectors. It's not incapable, though. >If I sell it, will it work on a Macintosh? To my knowledge, no. >And how good are the Laser 3.5 drives? Are they compatible with the >Apple 3.5 drives or do they have similar problems with the Unidisk? I don't know much about the Laser 3.5 drives, so I won't try to answer that. UUCP: {uunet!rosevax, amdahl!bungia, chinet, killer}!orbit!pnet51!shawn INET: shawn@pnet51.cts.com
blackman@phoenix.Princeton.EDU (Scott Michael Blackman) (02/18/89)
In article <9305@bloom-beacon.MIT.EDU> dcw@athena.mit.edu (David C. Whitney) writes: |In article <25945@apple.Apple.COM> keith@Apple.COM (Keith Rollin) writes: |>Nope. There are smarts in the Unidisk that prevent it from working on a Mac. I |To clarify: it *will* work on a mac as long as you open the drive up |and perform some brain surgery. It's a pretty simple job - just a |matter of pulling a couple of connectors and replacing another. IT |WILL VOID YOUR WARRANTY. I know this works as I've done it myself, and |the drive has been happily driving on my dad's mac for about 3 years. Could you post how this might be done? Does it work for a IIgs? |Dave Whitney A junior in Computer Science at MIT |dcw@athena.mit.edu ...!bloom-beacon!athena.mit.edu!dcw dcw@goldilocks.mit.edu |I wrote Z-Link. Send me bug reports. I use a //GS. Send me Tech Info. |"This is MIT. Collect and 3rd party calls will not be accepted at this number." Scott Blackman blackman@phoenix.princeton.edu blackman@pucc.bitnet ...allegra!princeton!phoenix!blackman
ALBRO@NIEHS.BITNET (02/19/89)
{_I have been using the Laser 3.5 drives for some time. They are directly
Mac-compatible, but require Laser's "univerrsal sal drive controller card"
to
work on a IIe or IIgs. They are not fast enough to profit from the 2:1
interleaving, and have about the same speed (my vague impression) as the
Unidisk in 4:1 format. They are more "transparent" to the system than the
Unidisk, in that they work as well as the Apple 3.5 drive when the IIgs
finds its boot drive on a "scan". So far I have been very happy with them.
-Phil Albro-
ALBRO@NIEJHS.BITNET
Disclaimer: The govt. does not endorse products, nor are my comments in any
way those of the govt. This is simply a negative problem report.-Rich-@cup.portal.com (Richard Sherman Payne) (02/20/89)
Even though the interleave is application independant, the easiest way to set it is with GS/OS. GS/OS can tell the difference between the Unidisk and the Apple 3.5 drives, and it will not format a 3.5" disk on a Unidisk at 2:1 interleave. But on the Unidisk, 2:1 is much slower anyway. The Unidisk is a smart drive, and does not accept low level commands from the software. If you have Unidisks, dont worry about 2:1, or have a friend format a disk at 2:1 and check it out. I have heard of other utilities which can set different interleaves, but I dont know what it is, nor where it is available. Rich -Rich-@cup.portal.com
dcw@athena.mit.edu (David C. Whitney) (02/21/89)
In article <6476@phoenix.Princeton.EDU> blackman@phoenix.Princeton.EDU (Scott Michael Blackman) writes: >In article <9305@bloom-beacon.MIT.EDU> dcw@athena.mit.edu (David C. Whitney) writes: > >|To clarify: it *will* work on a mac as long as you open the drive up >|and perform some brain surgery. It's a pretty simple job - just a >|matter of pulling a couple of connectors and replacing another. IT >|WILL VOID YOUR WARRANTY. I know this works as I've done it myself, and >|the drive has been happily driving on my dad's mac for about 3 years. > >Could you post how this might be done? Does it work for a IIgs? I don't remember the exact procedure, but it's fundamentally easy. As it says above, THIS VOIDS YOUR WARRANTY. Also, I'M NOT RESPONSIBLE FOR YOUR OWN MISTAKES OR THE POSSIBILITY THAT THIS PROCEDURE IS ALL WRONG. Here's the deal: Open the drive up. You'll notice that the incoming cable is connected to a PC board. This is the "smart" part. This "first" board connected to another board by an electrically equivalent plug as the incoming cable. Pull the incoming cable out of the current board, and pull the connecting cable from both boards. Now plug the incoming cable into the "second" board. This will do it as far as functionality is concerned. The hard part is closing the case up. You have to be careful while pulling/pushing plugs. They're hard to reach, and they are pretty solidly plugged in. Have fun... Dave Whitney A junior in Computer Science at MIT dcw@athena.mit.edu ...!bloom-beacon!athena.mit.edu!dcw dcw@goldilocks.mit.edu I wrote Z-Link. Send me bug reports. I use a //GS. Send me Tech Info. "This is MIT. Collect and 3rd party calls will not be accepted at this number."
PJBURTNESS@UALR.BITNET (02/21/89)
So far the only drives, besides apple's, that work well with the GS are the new 3.5 drives comming from applied enginering.