BlueSCSI and Mixing SCSI Drivers Question

[rikerjoe]

Hey all, I just got done with some partial experimentation that is leading me to a question. The experiment consisted of an internal BlueSCSI and an external BlueSCSI. All of my original drive images were formatted with Lido, since I started with it a long time ago before folks noted the negative impacts to drive performance when compared to other benchmarks. I though I'd try experimenting with a custom drive created with Disk Jockey to see what happens if I use the SCSI driver built into it. I could not get the image to mount despite being visible to various SCSI Tools. I tried reformatting and mounting with SCSI Director, still no joy. It wasn't until I reformatted the image hosted on the external BlueSCSI with Lido could I get the image to mount.

Clearly there is something I don't understand about SCSI drivers, disk images, and the like. Because I have so many disk images already formatted with Lido, I'm tempted just to stick with it. However, we're not true tinkerers unless there is a learning experience to be had, and that is where I am.

1) Is there a way to swap out the SCSI driver on a Lido-formatted image without destroying the contents of the image?
2) What is the explanation behind booting from a Lido-formatted image preventing the mounting of images that contain other SCSI drivers?
3) What does the actual structure of the drive look like (meaning where is the SCSi driver contained within the image)?

Oh, and in case this is a MacOS version thing, I ran the experiment under System 7.1.

 

[VicNor]

1. When you upgrade your OS Apple installs new Apple drivers on your hard disk. So I guess it's possible. But given how easy it is to just drag and drop the content of one drive to another (and that it's easy to create new drives on a SD card). You might be crossing the river to get water, when trying to swap drivers.

2. Good question. Top of mind, there's probably some compabliity issue at play. For instance, a Lido driver locks up a Macintosh Plus and prevents it from finishing the self test when you turn it on.

3. Depending on your version of driver, it can differ. In general, you got 31k of partition map. 16k (sometimes more) of SCSI driver. Then the rest is partition. You can see that in the partition info (Partition - Get Partition Info) in Lido.

Also, be aware that sometimes the SCSI driver gets loaded into RAM so the OS use the same driver on more than one hard drive. So I would recommend you to only stick to one driver. Apple's driver 43 seems to work quite well with BlueSCSI.

 

[eric]

Just to be clear, this is nothing to do with BlueSCSI - it's just that BlueSCSI is really the first time people shared images like this so we noticed. If you mix the same drivers are real HDD you'll get the same results

RE: #1. Sure! Every disk formatting utility has an "Update Drive" button, Apple HD SC, Drive Utility, etc. You will need to reboot after. I'd recommend upgrading all of yours to atleast the Apple ones that came with your device. I've tried to remove LIDO from any image I made.

 

[rikerjoe]

One would think this would be simple, but apparently I am an idiot. I am unable to update the drivers on any mounted volumes on a classic Mac, no matter what utility I use (SilverLining, Drive Setup 1.5/1.7.3) because the options are grayed out. I can't figure out how to update the disk drivers in Basilisk II, I get an error and it crashes when I try to use those tools on the mounted volumes. Formatting an .hda disk in Basilisk II makes it unreadable on the Classic Mac when I put the SD card in myBlueSCSI - I get the blinking question mark. Seems that my LIDO-formatted disk images work just fine for me, at least I understand it and it gives good information in the tool itself.

What am I missing here? Treat me like I'm an idiot, because apparently I am.

 

[eric]

. I can't figure out how to update the disk drivers in Basilisk II,

Basilisk II doesn't know anything about SCSI, it just finds something that looks like an HFS partition in the file and mounts that.

options are grayed out

Are you trying to update the drive that is currently running the system? It can't update the drive running the system, usually.