Page
D-2
Appendix D
AM-6000 Computer Owner's Manual, Rev. 00
Figure A-1 shows an extended active external narrow SCSI connector and bail locks for holding the
terminator in place. This configuration is used on almost all of Alpha Micro's currently available
product. The terminator is installed by sliding it over the connector and then latching the bail locks into
the notches in the terminator.
ATTACHING EXTERNAL DEVICES
To attach an external SCSI device, you must remove the terminator from the external SCSI port.
However, you must make sure the SCSI bus is still terminated at both ends. To do so, install the external
active terminator in the unused SCSI I/O port of the external SCSI device.
Attaching an external narrow SCSI device, such as a CD-ROM drive, to a system using the Wide SCSI
bus is a special case. You must make sure all 16 lines of the Wide SCSI bus are properly terminated. To
do so:
1. Use an external wide to narrow SCSI cable which actively terminates the “high” nine lines of
the Wide SCSI bus. Alpha Micro offers this cable in both three foot and six foot lengths
(PDB-00440-80 and PDB-00440-81).
2. Plug the narrow active external terminator (PRA-00222-21) into the unused SCSI I/O port of the
external device. This terminates the “low” half of the SCSI bus.
Notice that, in this configuration, the Wide SCSI active external terminator (PRA-00222-20), which is
normally plugged into the external SCSI port, is not used.
TERMINATOR POWER
For information on how to configure terminator power, see the following documents:
•
SCSI Disk Drives Installation Instructions, PDI-00436-20, revision A12 or later.
•
AM-625/626/627 SCSI 1/4" Streaming Tape Drive Installation Instructions, PDI-00625-00,
revision A05 or later.
•
AM-647 DAT Tape Drive Installation Instructions, PDI-00647-00, revision A02 or later.
•
The configuration document accompanying your disk drive.