![Alpha Microsystems AM-6060 Скачать руководство пользователя страница 85](http://html1.mh-extra.com/html/alpha-microsystems/am-6060/am-6060_owners-manual_2905713085.webp)
Page
D-2
Appendix D
AM-6060 Computer Owner's Manual, Rev. 00
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.
For most reliable Wide SCSI-2 performance, it is critical to follow the bus length limitations of
the SCSI specifications. If you want to attach more than one external device, you need to install a
Wide SCSI repeater inside the AM-6060 chassis. For more information, please see AM-441 Wide
SCSI Repeater Installation Instructions, PDI-00441-00. Depending on your configuration, you
may need a repeater even if you have only one external 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-62x 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.
•
AM-650 Wide SCSI ¼” Streaming Tape Drive Installation Instructions, PDI-00650-00.
•
The configuration document accompanying your disk drive.