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Imaging SCSI2SD for 7.5.5

CYB3RBYTE

Well-known member
Now that I've gotten my SE/30 running, I'm trying to setup my SCSI2SD V5.2 for macOS 7.5.5. I've been using BasiliskII and SavageTaylors guide, but I can't seem to get the image written to the SD card correctly (a 4GB SDHC).

I get an initial "Welcome to Machintosh" but then it freezes and I don't get any other hard drive activity from the SCSI2SD. I've been using BalenaEtcher to write the image. Any ideas?
 

LaPorta

Well-known member
Any chance you can start from a floppy, then use patched HD SC setup to format the card on the SE itself?
 

Phipli

Well-known member
Is this any help? Let me know if it needs updating.


Otherwise it might be a hardware issue :/
 

CYB3RBYTE

Well-known member
Is this any help? Let me know if it needs updating.


Otherwise it might be a hardware issue :/

I will try this and report back! Thanks!
 

LaPorta

Well-known member
Just did that, the SD does show up correctly on that Mac and in newer Macs running 10.5.
That is exactly what I have found: doing the formatting on the target machine makes it work properly more reliably than the "image from a newer machine" method.
 

CYB3RBYTE

Well-known member
Thank you Phipli! The process you linked to was much more straightforward! I got everything all imaged up on my modern Mac, then setup the SCSI2SD settings as instructed and bam! The chicken on the restore boot image was quite funny to see.

I should state that just before I tried that, I did get the system image from SavageTaylor working as well, just had to use dd on my 4,1 MBP running 10.5. Stuck with the restore disk from the QuickStart guide as it was more featured!

I think my replacement ROM may have had something to do with it as well, because it wouldn't load even my 7.5.3 Patched HD SC setup disk. It's running fine on the stock ROM. I'll have to do some fiddling.
 

Scribe

Active member
Is this any help? Let me know if it needs updating.


Otherwise it might be a hardware issue :/
An excellent guide!

I am confused about one thing: You wrote that for Device 1, the numbers put into "Device Type, Start sector, Sector size and Device size ... are critical". Why does Device 1 need to be only 200 MB? Why not just make it 2 GB (or 8 GB, or whatever)?
 

Phipli

Well-known member
An excellent guide!

I am confused about one thing: You wrote that for Device 1, the numbers put into "Device Type, Start sector, Sector size and Device size ... are critical". Why does Device 1 need to be only 200 MB? Why not just make it 2 GB (or 8 GB, or whatever)?
Because you're matching the settings to the pre-made image. The image is formatted as that, and the partition table that forms part of the drive formatting knows it is that. This is designed to be a quickstart so I avoided any and all possible sources of complexity. You are able to create additional partitions and disks if you are comfortable doing so though.

You could easily set the second disk to be whatever size you like and reformat it. The first disk is designed to be a recovery disk for people who don't have any install media.
 

Scribe

Active member
Because you're matching the settings to the pre-made image. The image is formatted as that, and the partition table that forms part of the drive formatting knows it is that. This is designed to be a quickstart so I avoided any and all possible sources of complexity. You are able to create additional partitions and disks if you are comfortable doing so though.

You could easily set the second disk to be whatever size you like and reformat it. The first disk is designed to be a recovery disk for people who don't have any install media.
Got it.
So what if I want to use a SCSI2SD with cards of different capacities? I have a few old cards laying around that have no other use. One is 8 GB and another is 256 MB. Do I need to re-setup the SCSI2SD every time I switch cards?
 

mdeverhart

Well-known member
Correct, for the S2SD the drive parameters are stored on the S2SD itself, while the actual drive data is stored on the SD card. I’d probably recommend that you put a suitable SD card in, configure it, and just leave it rather than swapping around. The SD cards also just contain the raw drive data, and can’t be read directly in another computer.

The ZuluSCSI and BlueSCSI handle this differently - the SD card is formatted as a normal SD card (ExFAT or FAT32), and the drive data is stored in image files (one image file per virtual drive). Any drive configuration, if needed, is set based on the file name, a INI configuration file, or automatically extracted from the image file (for example, the drive size).
 

Scribe

Active member
The SD cards also just contain the raw drive data, and can’t be read directly in another computer
I'm sure you know a lot more about this stuff than I do, but my experience contradicts that statement...

Before I set up a MacIPpi (much thanks to @mactjaap), I was transferring files to and from a Mac SE by taking the SD card out of the SCSI2SD and putting it into a card reader attached to a 12" PowerBook G4 (running OS X Tiger). The PB wouldn't see any data from the second SCSI ID, but the partitions that are in the first SCSI ID would all mount as volumes on the PB.
 

Phipli

Well-known member
I'm sure you know a lot more about this stuff than I do, but my experience contradicts that statement...

Before I set up a MacIPpi (much thanks to @mactjaap), I was transferring files to and from a Mac SE by taking the SD card out of the SCSI2SD and putting it into a card reader attached to a 12" PowerBook G4 (running OS X Tiger). The PB wouldn't see any data from the second SCSI ID, but the partitions that are in the first SCSI ID would all mount as volumes on the PB.
That's because the first "disk" is right at the beginning and if the computer can read its partition table etc and if compatible can mount it... but, that doesn't mean that you can do much with the other disks. It's still true that the card isn't formatted for use in a card reader. The SCSI2SD sort of acts as a pass through of the raw blocks of the media (let's not get into how an MCU on SD cards emulates continuous media from a broken array of media) and just presents portions of it as independent devices to the SCSI host.

You could make a normally formatted SD card work in both a card reader and old mac by using the whole thing as a single disk. Otherwise, like you noticed, the first "disk" shows up. You can also do fancy things if you know the block ranges, to mount later drives manually.
 

mdeverhart

Well-known member
Thanks @Phipli, that’s a better explanation of how it works. I hadn’t considered the “parse the partition table at the beginning of the card” scenario. That makes sense.
 

Scribe

Active member
That's because the first "disk" is right at the beginning and if the computer can read its partition table etc and if compatible can mount it... but, that doesn't mean that you can do much with the other disks. It's still true that the card isn't formatted for use in a card reader. The SCSI2SD sort of acts as a pass through of the raw blocks of the media (let's not get into how an MCU on SD cards emulates continuous media from a broken array of media) and just presents portions of it as independent devices to the SCSI host.

You could make a normally formatted SD card work in both a card reader and old mac by using the whole thing as a single disk. Otherwise, like you noticed, the first "disk" shows up. You can also do fancy things if you know the block ranges, to mount later drives manually.
OK. That makes sense.

So what is the value of having different SCSI IDs on the same physical card? You could also just have one ID with a bunch of partitions on it. Then all of the data is accessible on old Macs and also more modern Macs (but not the most modern Macs).
 

Phipli

Well-known member
OK. That makes sense.

So what is the value of having different SCSI IDs on the same physical card? You could also just have one ID with a bunch of partitions on it. Then all of the data is accessible on old Macs and also more modern Macs (but not the most modern Macs).
Some macs don't like booting from multiple partitions but are able to boot from multiple disks. If you have multiple "disks", if you corrupt one and have to reformat you only lose that one. You can emulate a CD Drive with one.

There are some various reasons, but you're not required to do one or the other. Both have advantages, it sounds like partitions and one device is the best option for you.
 
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