Macintosh Disk Interfaces

Summary: Macintosh Disk Interfaces, IDE, SCSI, IEEE 1394 (FireWire), USB. How to mount Macintosh disks on a PC.


For a very long time, all hard disks installed on Apple Macintosh computers were SCSI disks (Small Computer System Interface). All removable drives (notably SyQuest drives) were also SCSI. Recently, Apple began to install also IDE hard disks and USB (Universal Serial Bus) removable drives, then IEEE 1394 (FireWire).

SCSI Disks on a PC

To connect a SCSI drive on a PC, you must have a SCSI adapter (board). Such a board is rarely installed on off-the-shelf computers. Therefore, you have to add the SCSI adapter afterwards.
The price of SCSI adapters varies greatly, from about 30 $ to several hundred dollars. If you only have to install a SCSI bus on a computer to read Macintosh disks, cheap adapters are often enough (for an example, the 2904 adapter from Adaptec).
You can also find parallel/SCSI adapters and USB/SCSI adapters. Those devices allow you to connect a SCSI drive to a USB bus or on a parallel port. They are often as expensive as real SCSI adapters and their only real advantage is that you don't have to open the computer to install the board (it can be interesting with laptops, already full computers of in the case of temporary connections). The performances are often poor in the case of the parallel port.
MacDisk was tested with numerous SCSI adapters, with several parallel/SCSI adapters, with PCMCIA/SCSI adapters. If you want to check, download MacDisk. Contact us if you have a doubt.

IDE Disks

IDE hard disks installed on Macintosh computers are often internal disks. Therefore, it happens rarely that you have to mount such a disk on a PC.
It can nevertheless happen. Physically, Macintosh IDE disks are connected like another IDE disk (select the bus, the master/slave position, etc.).
MacDisk can access such disks, but only under Windows NT, 2000 and higher (and not under Windows 95/98/ME). As a matter of fact, low-level drivers under Windows NT to Windows 7/8 consider all disks as SCSI drives and the access methods we use (SetupDI interface) work well with IDE disks.

USB Drives

Those drives are nowadays well standardized.
MacDisk access those drives under all versions of Windows. Under Windows 2000 and higher (up to Windows 7/8), you'll have to use version 8.0 or higher of the program.

FireWire Disks

Under Windows 2000 and higher, all drives are handled by the Lsdiorw service. A version of this service exists for all versions of MacDisk.

Thunderbolt Disks

Thunderbolt disks are not yet supported by current version of MacDisks (8.0). We intend to add this feature as soon as possible.

Hardware Compatibility

In the Macintosh-PC direction, all kind of drives can be mounted if the target computer supports the correct interface (that is, have an USB port for an USB drive, etc.). There should be no hardware compatibility problems with the correct equipment on the PC.
In the other direction, there is no way to connect a parallel port drive on a Macintosh, since this computer has no parallel port. All other interfaces exist.

How to Manage Current Huge Disks?

One can nowadays find on the shelves huge USB or FireWire disks (do you remember when 120+GB disks were huge disks?). Here are some comments that can be useful to know how to use such huge volumes to share data between Macintosh and Windows computers and above all to know the limits.

Pierre Duhem (ex-Logiciels & Services Duhem)
3, rue Pierre Haret - F-75009 Paris (France) - Tel. (+33) [0]149 700 455