To start with... SCSI2SD access SD cards in raw mode (like Gotek with no custom firmware), so doesn't matter if is formatted with fat32... The format will be destroyed when SCSI2SD utility prepares the card for usage. This also means you can't transfer files from the card to another PC by direct mounting it on Windows (on linux is possible but you need to do some jumbo mumbo for that).

Then, you have to prepare the card for boot from the PC you will use it with SCSI2SD (the well known fdisk/format/sys steps). Also you need to check the disk geometry limits of your SCSI card (generally 4 or 8GB) and configure your SCSI target with the appropriate size for that. Failing these steps results in a non-bootable SCSI2SD (the same applies for Mac). You can latter configure a second SCSI target with the rest of the size on your card for applications (but as i said before, you will not be able to transfer directly to it).

If i remember well, ImDisk or Arsenal Disk Mounter can mount filesystems from devices based in block starting and total size, and then you can mount the chunks created by SCSI2SD and access the content... But I never have tested such scenario.

Wait, can you not just take the SD card out and put files on it and plug it back in?

Can you even do that with a SD to IDE adapter?

JustRob wrote on 2021-12-21, 19:46:

Wait, can you not just take the SD card out and put files on it and plug it back in?

No. Unfortunately isn't a passive adapter, and that's how it works (probably due performance and internal buffer/memory size restrictions). Dunno about IDE to SD adapters, never had one, but you should be also restricted due geometry discrepancies between using a normal SD Host Controller, and one which has to manage the geometry of IDE bios scenarios (unless it writes all to a single file in the card).

That blows. One of the major selling points was that I could plop the SD card in my modern PC, copy the Windows 98 installation before making changes, and then put it back if I mess something up.

JustRob wrote on 2021-12-21, 20:00:

That blows. One of the major selling points was that I could plop the SD card in my modern PC, copy the Windows 98 installation before making changes, and then put it back if I mess something up.

You still can backup your installs if you use tools like dd, dfsi/dfso or similar... By using the block offset, size and total block count to make images of your scsi2sd card "partitions" and write to them. In fact that's how the MacOS tutorials out there install, backup and restore their installs (as windows knows nothing about HFS and apple disk partition structures).

As for the rest... SCSI2SD was created with Mac and Synthesizers in mind, which have disk storage structures unrecognizable by PC OSs (except maybe linux with some work and magic), so is natural they preferred performance of raw mode than being able to mount the card directly in the PC, which would be worthless anyways in such scenarios. PC usage of the SCSI2SD in just an afterthought of its creators.

I don't think I can even mount the thing in the case I'm using, the stupid screwholes don't line up.

Meh, maybe I should just stick to regular hard drives. Thanks anyway

Edit:

hyoenmadan wrote on 2021-12-21, 19:38:

To start with... SCSI2SD access SD cards in raw mode (like Gotek with no custom firmware), so doesn't matter if is formatted with fat32... The format will be destroyed when SCSI2SD utility prepares the card for usage. This also means you can't transfer files from the card to another PC by direct mounting it on Windows (on linux is possible but you need to do some jumbo mumbo for that).

Then, you have to prepare the card for boot from the PC you will use it with SCSI2SD (the well known fdisk/format/sys steps). Also you need to check the disk geometry limits of your SCSI card (generally 4 or 8GB) and configure your SCSI target with the appropriate size for that. Failing these steps results in a non-bootable SCSI2SD (the same applies for Mac). You can latter configure a second SCSI target with the rest of the size on your card for applications (but as i said before, you will not be able to transfer directly to it).

If i remember well, ImDisk or Arsenal Disk Mounter can mount filesystems from devices based in block starting and total size, and then you can mount the chunks created by SCSI2SD and access the content... But I never have tested such scenario.

This doesn't work btw, the problem is Fdisk doesn't see the SD card in the first place. Only my SCSI configuration utility sees it.

Too many variables there. First of all, would be your SCSI card BIOS doesn't support drives beyond 4 or 8GB as bootable Int13h drives. So 29GB as in your pics will not make it. You have to configure your target with less size in accordance with your card limits for bootable drives.
Then you have to enable int13 extensions on your card via its BIOS setup tool or SCSISelect bootable drive.
Then there is a possibility you may need an SCSISelect bootfloppy to configure the disk, not just raw FDISK.

All depends how you do it with real mechanical drives on your configuration actually.

How do I know if my SCSI controller doesn’t allow drives beyond 4GB or 8GB? I searched for the specs online, but all I could find is that it has a data transfer cap of 20MB/s.