Apple Macintosh LC - Manual (Page 132)

1. With the SCSI device switched off and unattached to the computer or other
SCSI devices, locate the ID number and the ID number switch on the back panel
of the device.
2. Insert the point of a pushpin or an opened paper clip into the ID number
switch and push gently until the number you want is showing.
The number increases to 7, then starts over at 0. Some devices have blank
spaces between the numbers 7 and 0.
Daisy-chaining SCSI devices
SCSI devices can be linked together by cables to form a chain. The
arrangement of devices in a SCSI chain does not determine their priority in
communicating with the Macintosh; the devices' ID numbers determine
priority.
You use special cables, called SCSI cables, to connect SCSI devices to the
computer and to one another in a chain. You attach a SCSI cable to the SCSI
port on the back panel of the Macintosh and the port on the SCSI device. Each
SCSI port is identified by the SCSI icon.
To assure accurate transmission of information between the computer and the
SCSI devices connected to it, there must be a special connector called a SCSI
cable terminator at each end of a SCSI chain. SCSI terminators can be
internal -- there's a built-in terminator in the Macintosh LC, for example --
or external.
Most SCSI devices don't have built-in terminators, so you'll probably need to
add an external terminator to the final device in the SCSI chain. If one of
your external SCSI devices has a built-in terminator, connect that device
last in the chain.
If more than one of your external SCSI devices have built-in terminators, you
must have the terminators removed from all but one of the devices. (If you
are not sure whether a SCSI device has an internal terminator, refer to the
manual that comes with the device or ask your authorized Apple dealer.)
Table 16-1 shows how to arrange SCSI terminators with several different
configurations of equipment.
Table 16-1 Guidelines for using terminators when connecting SCSI devices
to the Macintosh LC
The manual that comes with all Apple SCSI cables and terminators includes
detailed instructions for connecting the cables and terminators to various
devices.
!! IMPORTANT: Always switch on your SCSI devices before switching on your
computer. Doing so ensures that the computer will recognize all the devices
in the SCSI chain. !!
Connecting non-SCSI devices
The Macintosh has several ports on the back panel of the computer to which
you can connect other types of peripheral devices. Each port is marked by a
distinctive icon. In most cases, the same icon is used to mark the port on
the device and the connecting cable.