Setting up your vintage (classic) 68k Macintosh – Using a SCSI2SD adapter

SCSI2SD adapter card

SCSI2SD adapter card

I recently purchased a SCSI2SD V.5 adaptor (3.5″ and 2.5″) to replace a failing 1980s SCSI HD, and realized once I had it set up I could “image” the Micro-SD card to make boot-able images anyone could use.

So, similar to my entry on setting up using a floppy disk, and setting up using an Iomega Zip Drive, I created boot images for System 6.0.8 and System 7.5.5.


  1. Your classic 68k Macintosh turns on, and is prompting you to insert a disk.  If your 68k Macintosh does not turn on, or does not show the insert disk icon, you may need to do some repair work before you proceed.
  2. Your classic 68k Macintosh supports an internal SCSI hard drive, and/or an external SCSI hard drive, although you will need to have an enclosure or an external adapter for your SCSI2SD adaptor so to use it externally.  Note, for Powerbook systems that only support 2.5″ SCSI drives, a Powerbook Edition of the SD2SCSI adaptor can be used to replace the internal drive.
  3. You have a SCSI2SD adaptor, you MAY be able to use these images with a Compact Flash card of the correct size and a CF2SCSI adapter, if you can, let me know.
  4. You have a 4GB, 8GB, 16GB or 32GB SD or MicroSD card you plan to use with your SCSI2SD adaptor.

Step 1: Determine if you can use this method

This method will work for the majority of 68k Macintosh computers except: The 128K, 512K, 512Ke.  These three 68k systems do not support internal or external SCSI.  You will need to use one of the other setup methods I’ve previously identified, with the best option being buying and using Floppy-Emu to boot from 400KB SS SD floppy disk images.

Step 2: Selecting your boot disk image

First determine which operating system you can, or want to run on your classic Macintosh.

I’ve made 2 main types of bootable images, both formatted using the Hierarchical File System (HFS):

  1. An OS 6.0.8 Bootable image for older 68k systems that may only have 1MB of memory installed.  The SE/30, Classic, Classic II, Portable, II, IIx, IIcx, IIci, IIsi, LC typically shipped with only 1 MB of memory.  I’ve managed to track down a scan of the Apple Memory Guide from November 2000 (pdf) that shows how to upgrade the memory for these and other 68k systems.
  2. An OS 7.5.5 Bootable image for the remaining 68k systems that have 2MB or more memory installed.

I’ve created 4 different sizes of each image, a 4GB, 8GB, 16GB and 32GB.   Note, the 32GB SD has been setup as 2 disks, of SCSI ID 0 and SCSI ID 1, this is to address various limits for the number, size, and file count for partitions under these older operating systems.

Each image contains:

  • The system folders for both System 6.0.8 and System 7.5.5, containing the “minimal” files to boot, with only one of them “blessed” to be the startup system
  • A single 512MB Partition, the rest of the disk(s) are not partitioned, and are uninitialized so you can set them up how you want.
  • The minimum boot files in the system folder to boot
  • A patched version of HD SC Setup 7.3.5 for formatting your SCSI HD or equivalent once you’ve booted your Macintosh (patched to support non-Apple SCSI Drives)
  • Disk Copy 4.2 by Steve Christensen (for Apple) for creating image files from floppy disks, or writing images back to floppy disks
  • StuffIt Expander 5.5 (freeware, installed and installer) by Aladdin Systems, for opening StuffIt and other archive files (.arc, .bzip, .bin, .cpt, .dd, .gz, .hqx, .lha, .img, .lhz, .pkg, .sea, .sit, .smi, .tar,  taz, .uu, .Z, .zip)
  • ShrinkWrap Version 2.1 (last release before becoming an Aladdin product) by Chad Magendanz, for creating files that you can mount that emulate a floppy disk or hard disk.  I use this program to create 32MB ProDos image files that I can use to transport and backup the contents of my ProDos partitions I use with my Apple IIe card.
  • DropDisk by Mike Wiese and Chris Cotton that allows you to quickly mount and use disk images created with Disk Copy or ShrinkWrap
  • System Picker by Kevin Aitken that allows you to select which System Folder is active (blessed) on restart.
  • You can add additional applications / files to these image files by mounting them as a volume under Basilisk II, although I suggest testing your SCSI2SD adaptor and your 68k Macintosh with the basic images first.
OS     Zipped .img files
System 6.0.8 4GB 8GB 16GB 32GB
System 7.5.5 4GB 8GB 16GB 32GB

Step 3: Configuring your SCSI2SD adaptor

You will need to configure your SCSI2SD adaptor based on the size of SD or microSD card you plan to use.  Since I do NOT have a SCSI2CF adapter I can’t provide any guidance for you, or know if you even have to do anything.

  1. Download the correct setup software from CodeSRC, make sure you get the correct software based on your version of the adapter v3/v4/v5 vs. v6.   The software is available for Windows 32, Windows 64, Linux and Macintosh OS X.
  2. Run the setup software
  3. Connect the USB cable from your computer to your SCSI2SD adaptor

For a 4GB, 8GB, or 16GB card, select device 1, and set:

  1. SCSI ID = 0
  2. Device size = the size of your card, e.g. 4GB, 8GB or 16GB
  3. Sector count = should auto adjust after setting the device size
  4. You should be able to leave everything else as the default
  5. Select save to device
  6. Once saving is complete disconnect the USB cable from the SCSI2SD adaptor

For a 32GB card

  1. First select device 1, and set:
    1. SCSI ID = 0
    2. Device size = 16 GB
    3. Sector count = 33554432, should auto adjust after setting the device size
    4. You should be able to leave everything else as the default
  2. Second select device 2
    1. Check Enable SCSI Target
    2. SCSI ID = 1 (or some other number that will not conflict with anything else in your SCSI chain)
    3. SD card start section (check auto)
    4. Device size = 16 GB
    5. Sector count = 33554432, should auto adjust after setting the device size
  3. Select “save to device”
  4. Once saving is complete disconnect the USB cable from the SCSI2SD adaptor

Step 4: Creating your bootable HFS SD, microSD or CF Card

I’ve created a separate blog entry for how I write the images I create to the SD and CF Cards and how to create your own images if you done want to use one of mine.

4 thoughts on “Setting up your vintage (classic) 68k Macintosh – Using a SCSI2SD adapter

  1. Thank you very much! I can confirm that the instructions worked on macOS High Sierra and I was able to boot my Macintosh SE without a floppy. I should mention that dd took quite a while for me, around 3 hours.

  2. I’m getting an error from Chrome when I attempt to download these images: is dangerous, so Chrome has blocked it.

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