Compaq AlphaStation XP1000 Systems that include a SCSI bus currently use the Qlogic ISP1040C wide Ultra SCSI I/O processor card. At this time, Compaq supports up to four drives attached to the adapter's wide internal bus. Narrow devices can be attached to that bus when a 68- to 50-pin adapter is used. No external devices are supported on the same adapter used for internal devices. Add another SCSI adapter if you need to attach external SCSI devices.
For more SCSI configuration information, see:

• Configuring the SCSI Adapter
• SCSI IDs
• SCSI Termination
• SCSI Length

Configuring the SCSI Host Adapter

The SCSI adapter is configured using the eeromcfg.exe utility.

Configuring SCSI IDs

The Compaq AlphaStation XP1000 System currently supports up to four internal SCSI devices. The adapter can support SCSI IDs ranging from 0 to 15. Each SCSI device must have a unique SCSI ID. Typically, the host adapter is ID 7.

Note: The CD-ROM drive is an ATAPI device attached to the IDE port.

SCSI Termination

SCSI Termination is enabled on the MLB and there is a terminator at the end of the SCSI cable. No internal SCSI devices should be terminated. There are several ways to disable termination on SCSI devices, including removable resistor packs, switch settings, or a terminator plug. Refer to the device documentation for details.

SCSI Bus Length

For reliable operation of UltraSCSI devices, do not let the bus length exceed 1.5 meters (4.9 feet). The internal cable supplied with your system meets this specification.