Installation guide

1-4 Compaq 64-Bit/66 MHz Single Channel Wide Ultra3 SCSI Adapter Installation Guide
Compaq Confidential – Need to Know Required
Writer:
John Turner
Project:
Compaq 64-Bit/66 MHz Single Channel Wide Ultra3 SCSI Adapter Installation Guide
Comments:
final
Part Number:
154060-002
File Name:
b-ch1 Introduction.doc
Last Saved On:
7/21/00 1:21 PM
SCSI IDs
The 64-Bit/66 MHz Single Channel Wide Ultra3 SCSI Adapter contains one
SCSI bus that support up to 15 peripherals. The SCSI bus has internal and
external connectors. Peripherals on the bus must have a unique SCSI ID
ranging from 6 to 0, then 15 to 8, with 6 being the highest priority and 8 being
the lowest priority. SCSI IDs on all peripherals must be either manually set
with switches or jumpers on the device itself, or automatically set on Compaq
products that support hot-pluggable drives. The SCSI IDs determine the
priority of the peripheral device when attempting to access the SCSI bus. The
server assigns the SCSI adapter to the highest priority by setting the ID of the
adapter to 7.
Multiple Adapter Installation
The following considerations apply when you install more than one
64-Bit/66 MHz Single Channel Wide Ultra3 SCSI Adapter:
■
Each adapter has one SCSI bus with isolated LVD and SE connectors.
■
Each adapter supports one set of unique SCSI Ids (from 6 to 0, 15 to 8).
Each peripheral on a bus must be assigned its own unique ID.
SCSI Termination
All SCSI buses require termination on both ends of the bus to prevent signal
degradation. The 64-Bit/66 MHz Single Channel Wide Ultra3 SCSI Adapter
supplies the termination on the adapter end of the SCSI bus. Hot plug drives
do not require terminators on the ribbon cable, because terminators are
included on the drive backplane. Non-hot plug internal drives require
terminators on the ribbon cable. Individual SCSI devices in Compaq servers
should not contain bus termination.
Wide Ultra3 and Wide Ultra2 require multi-mode or LVD-only terminators
(rather than SE only terminators used with Wide-Ultra SCSI-3, Fast-Wide
SCSI-2, and Fast-SCSI-2).
External SCSI buses must also be terminated. This termination is supplied in
Compaq external storage systems. Individual SCSI devices in Compaq storage
systems should not contain bus termination.