Configuration; Narrow And Wide Scsi; Configuring Cables - HP P5389A - Intel Pentium III-S 1.4 GHz Processor Upgrade User Manual

Installing Your Controller

Configuration

SCSI devices must be configured before use. This configuration process includes
enabling or disabling SCSI termination for the devices and setting the SCSI IDs for
each device.

Narrow and Wide SCSI

The SCSI devices you will be installing can be either Narrow (8-bit) or Wide (16-bit)
SCSI devices. Wide SCSI disk drives allow data to be transferred at twice the rate of
8-bit devices. Some SCSI devices such as tape and CD-ROM drives still use an 8-bit
interface.
The Wide SCSI bus is backward compatible with Narrow SCSI devices, allowing
both types of SCSI devices to be used on the same controller. Narrow SCSI devices
must be connected to Channel 0 which supports the 8-bit bus.
IMPORTANT: If you use 8-bit and 16-bit devices on a single 16-bit SCSI cable, Wide devices
must be at the physical end of the bus. This ensures that the 16-bit signals are correctly
terminated.
Attaching a single-ended SCSI device to an LVD bus will cause the bus to run at Ultra SCSI
speed (20 MHz) for all devices.

Configuring Cables

CAUTION: The SCSI I/O ports supply 5V DC and are capable of delivering
approximately 2A DC current. Ensure that the interconnecting cables used are
adequate for this amount of current.
Adaptec SCSI RAID controllers have Wide SCSI busses with one internal and one
external SCSI connector for each bus.
Internal and external SCSI cables, connector adapters, and terminators can be
purchased from a supplier of your choice or directly from Adaptec through our online
web store at
www.adaptec.com
3-2 HP 2100S SCSI RAID Controller User Guide