Apple 6400 appendix Before you connect a device

Before you connect a device

Before you connect a SCSI device to your Macintosh, complete these tasks:

mMake sure each SCSI device connected to your Macintosh has its own unique ID number from 0 to 6. The computer itself (the main logic board inside it) has the ID number 7 and the internal CD-ROM drive has the ID number 3, making the ID numbers 0, 1, 2, 4, 5, and 6 available for additional SCSI devices. Make sure other SCSI devices you add to the chain do not use ID numbers 3 or 7. See the instructions that came with each SCSI device for information on checking and setting its SCSI ID number.

IMPORTANT If you use two or more devices attached to the same SCSI interface with the same ID number, your equipment could malfunction and you could lose data as a result.

mMake sure you have the appropriate cable for attaching the SCSI device to your Macintosh.

If the device is the first or only one you’re connecting, use a SCSI system cable to connect it to the computer’s SCSI port:

SCSI system cable

If the device is not the first one, use a SCSI peripheral interface cable to connect it to the last device in the chain:

SCSI peripheral interface cable

54Chapter 3