Apple IIGS: Disk Drive Slot Assignments

This article has been archived and is no longer updated by Apple.

Depending on the operating system and the available combination of drives,
the Apple IIGS can use disk drives in a number of different slot assignments.
Below are some guidelines for determining the slot assignments.

Under DOS, ProDOS 1.1.1, ProDOS 1.2 (ProDOS 8), and ProDOS 16, you may use
the slot number to refer to hard drives and floppy drives using an interface
card. Disks may also be called by ProDOS pathnames without regard to slot

The Apple IIGS SmartPort, controlled by the firmware in the IIGS, includes
the internal RAM disk and ROM disk as well as any external drives connected
to the SmartPort. These drives are referenced in slot 5 because the IIGS
takes SmartPort to be slot 5. There are exceptions in the use of the
SmartPort: it's not available under DOS or ProDOS 1.1.1.

ProDOS 1.2 (ProDOS 8) permits up to four devices connected to the SmartPort.
If four drives are found on the SmartPort, the first two drives are
considered to be in slot 5 (drives 1 and 2), and the last two drives are
"found" in slot 2 (drives 1 and 2). If the RAM disk is active, it occupies
slot 5, drive 2, and remaining drives are moved down in the sequence to slot
2, drive 1 and slot 2, drive 2, if necessary.

ProDOS 16 allows the SmartPort up to six devices, all found in slot 5; if
activated (from the Control Panel), the RAM disk occupies slot 5, drive 2. If
both RAM and ROM disks are both activated, the ROM disk will be found
immediately after the RAM disk. If RAM and ROM disks are available and if
only the ROM disk is activated (from the Control Panel), the ROM disk will be
found in drive 2.
Published Date: Feb 18, 2012