Mac OSX and SCSI-Does It Work?
 

I have a Blue & White G3 with a 400MHZ G4 ZIF processor upgrade, and 512MB of RAM.:cool: More importantly, the G3 came with the stock SCSI PCI card that came with the early model B&W's, to which I have attached an external 1GB hard drive and a DAT tape drive.

The problem is, OS X does not seem to recognize the external drive. It does not show up on the desktop, and I'm not sure what to do to make it show up. Does X come with SCSI drivers, or do I have to download them? If so, from where? Can I do some fiddling with the Disk Utility to maybe bring it up? The external disk shows up when I boot into OS 9 with no problem. And yes, I did upgrade all the way to 10.1.3. What's the story here?? :confused:

Thanks in advance for any useful suggestions.

I'll bet the SCSI tape is being recognized, but only at the lowest level---as a SCSI device, but with nothing to drive it.

If you run the Apple System Profiler, you'll probably see the device show up in the device list. (or run /Developer/Applications/IORegistryExplorer and navigate to SCSI.)

If, for example, you hang a SCSI hard disk on the bus, then the Mass Storage framework would pick it up and the drivers would load for a hard disk. (Or a Zip, etc.)

There is no tape framework in OSX, so a tape drive just sits unused. There was quite a bit of talk about designing one on one of the newsgroups (I forget exactly what it is: comp.os.mac.osx? comp.mac.darwin?).

So I'll need a driver for the tape drive if I want to do backups is what you're saying?

Anyway, my main concern is about the SCSI external hard drive. Can I make OS X recognize it, without having to download extra SCSI drivers?

Hello? Anyone?

So no one else has any issues with external SCSI hard drives and OS X?

Which SCSI Card is it? Are there internal SCSI drives?

is it the one that was added if you did a BTO with the Ultra-SCSI hard drives? I know a couple people with those cards in B/W G3's that don't work well under X, however i have a B/W G3 that came with OSXServer 1.x (ah.. those were the days) and its BTO SCSI card works fine.

Another problem might be that its a single channel SCSI card and if there are internal drives then the external port would not be recognized.

I'm not sure what model SCSI card it is, all I know is it's the common model installed on rev. 1 B&W G3s when they first came out. I will attempt to find out more about what card it is.

As for internal SCSI drives, I don't have any. Everything connected to the SCSI card is external.

macnut, I have my SCSI card that I saved from my B/W and installed it in my 867 quicksilver. It is the Adaptec 2930u card as I ordered it BTO also when I got my B/W. I use it for my SCSI HP scanner. There was a deep sleep issue with this card that would not allow my 867 quicksilver to go into deep sleep. Of course the card worked great in the B/W, If you go to Adaptec's web site and check under this card, they have a driver out for OS X that is suppossed to fix the deep sleep issue. Maybe you can find some info for your problem.
JohnB

I plugged an external Jaz drive into my WallStreet and it was recognized under OS X. I haven't tried a SyQuest yet, but I'd imagine pretty much any kind of Winchester SCSI drive is going to work, and you should not need a driver for it.

Pretty much any external HD will work, since the Storage classes handle generic devices of that type. As long as the device doesn't need a special driver, it will work. Very few, if any, SCSI HDs need special drivers. To do things like handle buttons on the drives, that's a special driver. But the Mac has never really cared about the button on the Zip; you eject in software.

There are generic drivers for HD, CD, DVD, and probably writable CD drives. These handle 90% of the devices out there.

As for tape, there is no support at any level higher than the actual SCSI bus. Someone could write a driver for a particular device and it would work well, but you'd need to provide all the higher levels of support. You could, for example, just create a /dev entry and publish your unix-style header containing IOCTL values, plus handle normal read/write/open/close semantics. The existing storage classes provide this functionality via a "BSD shim" layer, which matches the unix BSD disk driver layer to the storage class APIs below. But the storage classes also export APIs directly to other parts of the system via IOKit interfaces.

Rather than create a single-device tape driver, the better design would be to abstract all about tapes into a higher layer. For example, the unix mtio.h interfaces handle most unix needs for all tapes. You'd write the code to translate those APIs into lower-level calls on the device driver. The driver then issues appropriate commands to its device. If you plug in a different device, its driver loads and exports APIs up to the generic layer. It's a bit of work to get it all designed, and sometimes you need to see a few tape devices to figure out what's generic and what's not.

There's documentation of the storage framework in the developer docs, but I don't know whether that ships with the system.

I wish the A/UX drivers were open-sourced! I wrote a unix driver for the (long dead) Apple QIC-100 40mb SCSI cartridge drive back in '89, and it would be a good start toward a unix-only driver.

Also, the Linux community can't support the IIfx or Quadra 950, because its adb, serial and floppy are controlled by the onboard 6502 I/O Processor (IOP). I had put all of that support into A/UX too.

Is anything connected to the card recognized by the system profiler?
have you tried updating the device drivers using drive set-up in 9 (or X). I had a small (350mb) drive attached to my adpatec 2930 which was recognized by the OS X drive setup after I first reformatted it in OS 9.2.2. I switched to a larger IDE drive in the same physical space so it is not connected now.

In Conclusion....
 

Well, it turned out that my SCSI card needed a firmware upgrade. The card wasn't an Adaptec, but an Advansys SB 3940UA card, which I found out after cracking my G3 open and taking a peek. I found the site for the card, which apparently used to be Advansys.com, but is now http://www.initio.com.

I downloaded the firmware update, used the enclosed utility to flash the card in OS 9, then when I booted back into X, bingo! My external drive appeared as if by magic. All I have to do now is stop the Finder from crashing whenever I do anything that accesses my main drive, :rolleyes: and things should be golden.

Thanks again for all your suggestions. I hope my experience will help anyone else experiencing my problem.

I know this thread is old, but I wonder if anyone had much luck running SCSI tape drives under OSX. I have one I'd like to use for backups, but am holding off buying a SCSI card if it isn't going to work anyway.

I'd really like to be able to access the tape drive the way I could under Linux. From what I'm gleaning here that is a lost cause.

Anyone have any luck on this?

Get the Adaptec SCSI cards. They are the best known ones and have the least troublesome drivers. If had to do things over again, I would have gotten an Adaptec card. I would have had less trouble finding drivers when I upgraded to X.

Go to www.adaptec.com.

booting from internal SCSI drive
 

I have a B&W G3 with an Adaptec 2906 card. I installed a SCSI WD 9g internal drive. The drive is recognized on the desktop and I can backup to it. I'd like to use it as my primary drive. I unplugged the ATA drive, installed OSX on the SCSI, but after installation the computer acted as if there was no system available. When both drives are active, if I try to restart on the SCSI drive using Startup Disk, the computer defaults to starting in Classic.

Re: booting from internal SCSI drive
 

The 2906 will not boot in any computer; it does not have any BIOS to boot with. It would be too slow anyway. You need a Powerdomain 2930 or higher to boot on the Mac. Try to dig up a Powerdomain 2940UW or something.

Tape
 

Does the Adaptec card come with drivers for the Tape drives though. I know it comes with drivers for the SCSI. However I was under the understanding that actual device drivers for SCSI devices were supplied either by Apple or the company making the device (i.e. scanners)

I gather that Retrospect has drivers, albeit only for itself. So no using Unix utilities. But you can backup to tape.

the stock SCSI driver should be able to talk to any reasonable SCSI device. i just don't happen to have a tape drive so i can't get my hands dirty about it.

Could this be the same problem since I have a SCSI connected scanner and OS 10 just doesn't recognize scsi devices??

I have a G4 Mac and recently installed OS 10. I can run in OS 10 and Classic 9 mode. However, my Epson ES-1000C scanner will no longer work.

When I try to access my scanner through Photoshop - Acquire Scantastic or Twain it says my scanner is not found.

Can you help me?
Thanks so much for any advice.

You need to tell us more. What is the brand of your SCSI card (Adaptec, ATTO, etc.). Also what version of OS X did you install? Adaptec only supports 10.2 and lower. 10.3 and 10.4 don't work with these cards. If that's the problem, then get an ATTO card.