Fast-Wide Scsi-2; Tagged Command Queuing; Scsi Bus Connectors - Compaq ProLiant 5000 Reference Manual

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Fast-Wide SCSI-2

The SMART-2 Controller complies with ANSI SCSI-2 standards, supporting
both 16-bit Fast-Wide SCSI-2 (wide SCSI) and 8-bit Fast-SCSI-2 (standard
SCSI) devices. Fast-Wide SCSI-2 provides two bytes of data at each bus
transfer, doubling the data rate between SCSI devices to a maximum of
20 megabytes per second while still maintaining a 10 MHz bus rate.
Fast-Wide SCSI-2 controllers and devices must be able to communicate using
Fast-SCSI-2 protocol when required. Therefore, Fast-SCSI-2 drives may also
be used with SMART-2 Controller with the appropriate cable adapter.

Tagged Command Queuing

The SMART-2 Controller also supports tagged command queuing, which
allows SCSI hard drives to queue and sort multiple commands and then
execute the commands simultaneously.

SCSI Bus Connectors

The SMART-2 Controller has two Fast-Wide SCSI-2 bus connector ports, one
internal (Bus 1) and one external (Bus 2). This allows direct connection to
internal drives on one bus and external drives on the other. The internal port
may be brought out of the server chassis with a special internal/external cable
(supplied) to make both SCSI buses external.
The internal Fast-Wide SCSI-2 port is a standard 68-pin subminiature "D"
connector. This connector is accessible on the top edge of the board.
The external Fast-Wide SCSI-2 port is a standard 68-pin subminiature "D"
connector, mounted on the SMART-2 Controller slot panel and accessible at
the back of the server. Screw locks are provided for securing external SCSI
cables.
IMPORTANT:
to the server or in an external storage system, but not both. A configuration with
both internal and external SCSI hard drives requires more than one SCSI bus.
Writer: Project: Compaq SMART-2 SCSI Array Controller Comments:
All SCSI hard drives on the same SCSI bus must be either internal
File Name: M-ch9.doc Last Saved On: 4/22/97 1:01 PM
Compaq ProLiant 5000 Servers Reference Guide
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