External SCSI CD-ROM drives and CD Sunrise

[bigmessowires]

Because I'm not smart, I spent a couple of hours yesterday trying to get an external SCSI CD-ROM drive working on a computer that has a built-in CD drive. I'm curious why it didn't work. The computer is a Performa 6214CD running System 8.5, and I tried two different CD-ROM drives that are both different generic brands. With one CD-ROM drive, every known-good disc I inserted was rejected with "this disk is unreadable. Do you want to format it?" With a second CD-ROM drive, nothing happened when I inserted a disc.

I installed the CD Sunrise 2.2 extension on the computer, which I think is what's normally used to support third-party CD-ROM drives. One of these drives has definitely worked with CD Sunrise in the past on a different computer. It didn't work - no matter which CD-ROM drive was connected, I heard a beep while the extensions were loading and the CD Sunrise extension icon appeared with an X on it. The behavior when inserting discs didn't change from before installing CD Sunrise.

Any other brilliant suggestions for getting these two external CD drives working on this machine?

 

[Nixontheknight]

Because I'm not smart, I spent a couple of hours yesterday trying to get an external SCSI CD-ROM drive working on a computer that has a built-in CD drive. I'm curious why it didn't work. The computer is a Performa 6214CD running System 8.5, and I tried two different CD-ROM drives that are both different generic brands. With one CD-ROM drive, every known-good disc I inserted was rejected with "this disk is unreadable. Do you want to format it?" With a second CD-ROM drive, nothing happened when I inserted a disc.

I installed the CD Sunrise 2.2 extension on the computer, which I think is what's normally used to support third-party CD-ROM drives. One of these drives has definitely worked with CD Sunrise in the past on a different computer. It didn't work - no matter which CD-ROM drive was connected, I heard a beep while the extensions were loading and the CD Sunrise extension icon appeared with an X on it. The behavior when inserting discs didn't change from before installing CD Sunrise.

Any other brilliant suggestions for getting these two external CD drives working on this machine?

there is a version of Apple's CD-ROM extension that works with any CD-ROM drive, I think it came with system 7.6.1

 

[thellmer]

You made sure the external drives were set to an un-used SCSI ID and that you removed the terminator from the internal CD and moved it to the external? Those are the two things that usually cause issues like this...

 

[bigmessowires]

you removed the terminator from the internal CD and moved it to the external?

Umm... no I didn't. I did have a terminator on the external drives though. What does the SCSI bus topology look like when you have both internal and external SCSI drives? I never thought about that.

 

[cgp]

You need termination on both internal and external legs (although you may get away without). But you must have distinct SCSI IDs.

 

[Forrest]

Run SCSIProbe to confirm your CDROM drives have different ID’s

 

[MrFahrenheit]

Could the drives be going because of capacitor issues?

I have a stack of old Apple CDROM drives and none of them work, or work reliably. I’ve heard they all need recapping.

 

[Phipli]

Any other brilliant suggestions for getting these two external CD drives working on this machine?

The most common issue I have is solved by cleaning lenses.

Cleaning the Lens in a ’90s Apple CD Drive

Cleaning the Lens in a ’90s Apple CD Drive 90s CD-ROM drives frequently struggle to read CDRs (home written discs). Sometimes this can be helped by using another brand of disc or writing the …

stuffandnonsense.elephantandchicken.co.uk

I assume you checked the IDs, and confirmed that the ID selectors aren't disconnected and hardwired inside do they show up in SCSI Probe?

 

[Phipli]

that you removed the terminator from the internal CD and moved it to the external?

Not this, both internal and external chains need terminating.

 

[Phipli]

Umm... no I didn't. I did have a terminator on the external drives though. What does the SCSI bus topology look like when you have both internal and external SCSI drives? I never thought about that.

You want to terminate only the last device on the internal, and the external, chain.



If you only have an external CD connected, then usually you have a SCSI System lead from the computer to the drive, then a terminator on the other port on the drive. Which way around doesn't matter. Some drives have a switch for terminating and... Other things are options. But this is the norm.

The internal bus is probably already terminated, so unless other things don't solve issues, leave that be.

Download SCSI Probe. It will actually tell you if the internal bus isn't properly terminated if you run it with nothing on the external bus.

Could the drives be going because of capacitor issues?

I've only had cap issues with Caddy style drives so far, but it is possible.

 

[bigmessowires]

Hopefully I can find time to try this today. For the CD drive that did nothing when discs were inserted, I could imagine it's a SCSI id or termination problem. For the drive that complains all the discs are unreadable and offers to format them, I don't know. I can see how a dirty lens might render everything unreadable, but shouldn't MacOS know it's a CD-ROM and not suggest formatting the disk? It seems like it's treating it as a generic SCSI hard drive.

 

[Phipli]

For the drive that complains all the discs are unreadable and offers to format them, I don't know. I can see how a dirty lens might render everything unreadable, but shouldn't MacOS know it's a CD-ROM and not suggest formatting the disk?

This is normal for a dirty lens. Macs are constantly asking you to format CDs

For the CD drive that did nothing when discs were inserted, I could imagine it's a SCSI id or termination problem.

Do they spin up at all? It could be just a really bad lens / week laser, or a software driver issue. SCSI issues often cause issues for all devices on the chain.

Make sure you use commercial "pressed" CDs for testing, not home burned disks. Some old drives just plain hate burned disks (although a lens clean helps, along with using certain brands of disk, and burning them on the slowest setting).

 

[bigmessowires]

Drive #1 is a Plextor 12x. This drive used to work, a few years ago. It shows up under SCSI Probe or similar utilities. SCSI Probe seems to think the bus is terminated OK. When I insert a disc, the drive repeatedly spins up, runs for a few seconds, spins down, and repeats. After about 10 cycles it stops and the orange on/busy LED blinks 5 times, pauses, then 5 again... presumably an error code. The Mac never reacts to the disc at all.

This drive did sort-of work one time on my IIci under System 6, it said something like "The disk 'MacOS 8' couldn't be mounted because the drive is locked. Unable to create desktop file." then it ejected the disc.

Drive #2 is an NEC CD-ROM, unknown speed. Once again the SCSI bus looks OK. Under System 7 it successfully read three Mac-format CDs... hooray! This is the same drive that when connected to a different computer with OS 8.5 was complaining that every disk was unreadable. Either it magically fixed itself, or that was a symptom of a SCSI conflict or software problem.

OK so drive #1 probably has dirt on the lens or something, but I have no time to chase down more problems. Since #2 is already working, I'll sell or donate #1 as-is.

 

[NJRoadfan]

I can say for a fact that NEC drives work with CD Sunrise. I have several Plextor units, but I don't recall their compatibility. I think I used the universal Apple CD Extension for those.

 

[thellmer]

Not this, both internal and external chains need terminating.

Interesting. I'm by no means a SCSI expert but I thought you had to remove an internal terminator if you added an external device to the port and then terminate it there or at the end of whatever chain derived as I thought the chains just continued in series and were't in parallel legs external to the internal. Maybe I'm thinking PC-SCSI and not Mac. Or maybe I'm mis-remembering and thinking of when you added a second or third SCSI internal drive where you had to move the terminator packs around. I'd still bet you need to check for proper termination and SCSI-ID's among these devices. Generally CD devices are set to ID3 so the internal would already bet set to 3 and if you tried to add another external set to ID 3 then you'd run into issues like this. Run Tattletech or some other program to determine what SCSI device ID's are already in use and then set the external to something else...

 

[Phipli]

This drive did sort-of work one time on my IIci under System 6, it said something like "The disk 'MacOS 8' couldn't be mounted because the drive is locked. Unable to create desktop file." then it ejected the disc.

This error just means the CD isn't compatible with System 6. It's trying to rebuild the desktop so it can show it, but can't because the disk is read only.

 

[zefrenchtoon]

there is a version of Apple's CD-ROM extension that works with any CD-ROM drive, I think it came with system 7.6.1

Be careful that this version crash at startup when using it with a dvd rom drive.

Even if there is a hacked version of Apple CD/DVD driver to be used with any drives, I prefer to use Intech CD/DVD SpeedTools.

 

[Phipli]

Interesting. I'm by no means a SCSI expert but I thought you had to remove an internal terminator if you added an external device to the port and then terminate it there or at the end of whatever chain derived as I thought the chains just continued in series and were't in parallel legs external to the internal. Maybe I'm thinking PC-SCSI and not Mac.

I'm afraid you're misremembering this. It's the same on PCs, and any SCSI bus. Both the internal and external part of the bus need terminating at their extremity. SCSI has a few traps, it's not as plug and play and most of the good information has dropped off the internet.

Or maybe I'm mis-remembering and thinking of when you added a second or third SCSI internal drive where you had to move the terminator packs around.

You could be thinking of this. If you add an internal device you have to make sure there is only one terminator and that it is on the last device.

Sounds like you need to go and make sure your internal SCSI chains are terminated! I mean, it works some of the time, but it is one fewer thing that might cause unpredictable behaviour.