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RAID Array 3000 Controller Shelf Hardware User’s Guide
Compaq Confidential – Need to Know Required
Writer: Bob Young Project: RAID Array 3000 Controller Shelf Hardware User’s Guide Comments:
Part Number: EK-SMCPQ-UG. D01 File Name: c-ch2 RAID Array 3000 Controller.doc Last Saved On: 12/4/00 1:08 PM
The controller has two Single Inline Memory Module (SIMM) connectors.
The connectors form a mirrored pair when the controllers are configured in a
redundant controller configuration; otherwise they are fully accessible by the
controller. In a redundant controller setup, both controllers must have identical
cache configurations, and the total usable cache per controller will be half the
amount installed. Thus, in a single controller setup the maximum usable cache
is 64 MB while a redundant setup has a maximum usable cache of 32 MB per
controller.
RAID Array 3000
Controller Shelf
H0
Port 0
H1
Port 1
Write-Back
Cache
Module
2 Device Ports
Device I/O
Assy
Host I/O
Assy
Host
System 0
Host
System 1
Cache
Interface
Controller / Bus
Modules
RAID Controller
Ultra SCSI Wide
Single-Ended
Interface
To UPS
CTR Serial
Interface
UPS Control
Interface
Device
Storage
Shelves
Maintenance PC
SHR-1050
Ultra SCSI
Differential, Wide
Interface
Figure 2-1. RAID Array 3000 single controller block diagram