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Macintosh SE SCSI issues

I've been trying for a few weeks to get SCSI devices working on my Mac SE. I've got 2 800k drives, so no internal SCSI disk is installed. I've been trying to use a ZIP100 drive as a boot disk - but no matter what devices I have connected to the SCSI port, it fails to boot. I've got an active pass-through terminator and an active end terminator, so I believe my termination should be correct. The ZIP drive works 100% on an LC III that I have. Any tips/suggestions for this?

 
I never used terminators on an SE. Have you tried without? Have you tried a different SCSI I.D.? The issue could easily be the board itself.

 
I've just tried to boot it with no termination - doesn't detect the SCSI device, and when I use a boot floppy, it boots but stays waiting forever on the Finder. When I enable termination on the ZIP drive, same as ever - stuck looking for a drive.

 
Have you tried Cmd-Opt-Shift-Delete at power on to try booting from devices other than the selected boot disk?

I'd also try Cmd-Opt-Shift-Delete-# (where # is the SCSI ID)

Pardon me if these keystrokes came later than the SE, but I seem to remember they apply.

 
Still no luck. Just tried it with a few different termination settings, but still stuck waiting for a disk (the floppy doesn't show up, it's waiting right before that.) I'd like to get this board working with SCSI, but any tips would be well appreciated.

 
What systems are you running on each? The SE and the LCIII. And do you have the Iomega driver loaded on the SE?

 
LC III is running 7.5.5 - using LIDO. I've used the Iomega drivers before and they did work, but i've switched over to LIDO. SE is running 6.0.8, and I've been using the LIDO driver rather than the IOMEGA driver - the drive has worked fine with both drives. The issue occurs before the OS boot even begins. There's the first screen, then it changes to the screen where eventually on a working mac I'd get the Happy Mac, but no happy mac appears if any termination is on the SCSI drive, and if there is no termination but a connected device, then I get a Happy Mac/missing floppy, and when I insert a bootable disk, it gets stuck on the Finder.

 
Okay, thats the issue. I am pretty sure you need to use the Zip tools to format the disk. Version 3.5.3 I have and seems to work. There has to be a driver that gets loaded and the Zip software will do so and make the disk bootable.

If you think that is not the issue, make sure there is no internal drive hooked up. I have two dual 800k SEs that also have internal drives. One is actually my "archive" machine full of software, but has a 800k and 1.4mb drive.

 
I can confirm that there is not an internal drive in the SE - I've opened it up a few times. The Zip disk itself works fine the way I've formatted it on the LC III. This issue happens when ANY SCSI device is plugged in (as long as there's some sort of termination installed.) Is there anything I can replace on the board to fix this?

 
Oops, I meant to link to this keystroke cheat sheet: http://davespicks.com/writing/programming/mackeys.html

Does the SE need an internal SCSI terminator if no HD is installed? If so, perhaps it's disconnected, faulty, or missing.

Will the LCIII boot from the zip disk with no HD connected? If so, it sounds like hardware. If not, something resident on the LCIII HD is enabling Zip support, not the Lido driver on disk.

 
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Okay, well if it happens with any device then there is a good chance its the board. But FYI the SE and LCIII are not the same. The Plus is even worse when it comes to SCSI. So dont assume what works on one works on the other.

technight or uniserver probably know best as what is wrong and needs replacement.

 
rsolberg - I do have a pass-through terminator that should function similarly to an internal terminator. And yes, I have booted the LC III from a Zip disk with this specific drive. It's probably hardware, I just need to figure out if it can be fixed or if I'm better off getting another board somewhere.

 
The Zip drive does have  termination switch on the back next to the SCSI ID Switch.

The SE might not be able to boot from the Zip Drive unless it was formatted in a certain way. This is true for the Plus, SE\30 and Mac II Series (cx, ci, si, and so on), and its the same reason why they can't boot off a CD either.

Let me see... hmmm...

You have IOmega Disk Tools? If yes - format the zip disk with that on the SE and then put a system on it. Do not used "Erase Disk" from the Special Menu or HD Set up. Then drop and drag the System folder onto it and bless the system folder created by opening it and looking at its contents. This should Bless the System Folder.

The reboot and hope it works.

 
It's not an error with the disk - having the drive connected with any termination enabled (or any termination on the bus without a drive) means that the Mac will fail to boot.

 
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