Some people have had problems formatting a MacPeak external SCSI drive
(normally for the Macintosh) from an Apple IIGS. One user, who had this
problem, was working with an Apple IIGS with 1MB RAM, 3.5-inch and
5.25-inch floppy disk drives, and an Apple II SCSI card in slot 5.
The Apple IIGS recognizes the drive, but the format routine quits after
running for about the same time it takes to format a ProDOS floppy and then
crashes. A conflict between the SCSI card and the 3.5-inch drive causes
this problem.
The 3.5-inch drive plugs into the SmartPort. The SmartPort is slot 5. To
use the SCSI card in slot 5, you need to set slot 5 in the Control Panel to
"Your Card". When the Control Panel is set in this way, the SmartPort is
disabled, and the 3.5-inch drive is also disabled.
To use both the 3.5-inch drive and the SCSI drive on the Apple IIGS, place
the SCSI card in a slot other than slot 3 (the 80-column display), slot 4
(the mouse connection), slot 5 (the SmartPort), or slot 6 (the 5.25-inch
drive location). This leaves slots 1, 2, and 7 available. Slot 1 is often
used for a printer, slot 2 is often used for a modem, and slot 7 is used
for AppleTalk. Choose slot 1 if no printer is attached, slot 2 if no modem
is attached, or slot 7 if AppleTalk is not in use. No matter which slot you
choose, you must set the Control Panel to "Your Card" for that slot.
If, after reassigning slots, there is still difficulty formatting the
MacPeak drive, there would appear to be an incompatibility between the SCSI
card and the MacPeak drive. (MacPeak indicated that they do not support
the use of their drives on the Apple II SCSI card.)