Adaptec ASR-2000S, Руководство по установке

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Installing Your Controller
Wide devices allow data to be transferred at twice the rate of
Narrow devices. The Wide bus is backward compatible with
Narrow devices, allowing both types of SCSI devices to be used with
the same controller. The Narrow interface is still used with some
SCSI devices, such as tape and CD drives.
LVD and SE Devices
Attaching a single-ended (SE) SCSI device to an LVD bus causes the
bus to slow down to Ultra SCSI speed (20 MHz) for all devices.
Note: Adaptec RAID controllers cannot be used with older
SCSI 5-V differential (DE) devices.
SCSI Cables
Adaptec recommends you using Ultra160 SCSI devices and good
quality LVD SCSI cables, which can be purchased from Adaptec, at
www.adaptec.com
, or other suppliers.
SCSI Device IDs
The SCSI specification allows up to 7 SCSI devices (and a controller)
to be connected to a single 8-bit SCSI bus. A Wide SCSI bus can
support up to 15 devices and the controller.
All SCSI devices, including the controller, must be assigned a unique
SCSI ID. SCSI IDs, which are typically set using jumpers or switches
on peripheral devices, can be assigned any number from 0 to 7 for
8-bit SCSI devices or 0 to 15 for Wide SCSI devices.
Set the SCSI ID of each SCSI device attached to the controller to a
unique ID number between 0 and 6. The Adaptec RAID controller is
set to ID 7 by default (most SCSI controllers use ID 7). Wide SCSI
devices can also use SCSI IDs 8 through 15. SCSI IDs can only be
duplicated on the same controller if the devices using the same ID
are not attached to the same bus.
Combined RAID IG.book Page 3 Thursday, May 3, 2001 11:51 PM