If you try to start up from a 3.5" disk in a drive connected to slot 5, you
may encounter a problem if you have a Disk II drive connected to slot 6.
Unlike the UniDisk 5.25" drive, the Disk II drive can't deflect startup
attempts if it contains no disk. Instead, it keeps trying to read from a
disk that's not there. This is a problem when you want to start up from a
3.5" drive in slot 5.
There are three ways to start up from slot 5 if there's no disk in the
Disk II in slot 6:
- Enter the Control Panel and set the startup slot to 5. (After turning on
the computer, you have about a second to press Option-Control-Reset
before the Disk II drive starts spinning.)
The second and third methods can be used after the Disk II starts spinning.
- Press Control-Reset, which put you in Applesoft BASIC (with the ] prompt
at the left of the screen). Then type PR#5 to start up from slot 5.
- Press Option-Control-Reset, set the startup slot to 5, exit the Control
Panel, and press Control-Open Apple-Reset. This aborts the startup attempt
from slot 6 and makes slot 5 the startup slot.
If you need the SCAN option to work properly, you need a Unidisk, Apple
IIc External Drive, or an Apple 5.25" drive. These drives can be attached to
the Apple IIGS either at the SmartPort connector in the back, with a UniDisk
drive controller card, or in a daisy chain off an Apple 3.5" drive connected
to the SmartPort. The firmware that drives them can abort a startup attempt
if there is no disk in the drive.