Connecting SCSI Peripheral Devices

The A7173A adapter is capable of communicating with Low Voltage Differential (LVD) or Single Ended (SE) SCSI devices. LVD allows up to 12m cable lengths with multiple SCSI devices, or 25m point-to-point connections.

Important Rules For Connecting SCSI Devices

When you connect SCSI devices to an A7173A or AB290A Host Bus Adapter, the following rules apply:

All of the devices connected to each port must be of the same type; for example, you cannot mix hard disks and removable-media devices on the same port.
All of the removable-media devices (such as a tape drive, DVD, or CD-ROM) on a SCSI port must be of the same type and speed. For example, you can connect two or more 320 MB/S tape drives to a port, but you cannot mix tape drives of different speeds on the same port.
Each SCSI channel on the A7173A adapter has an internal HD (high density) SCSI connector and an external VHDCI (very high density cable interconnect) SCSI connector. Do not connect SCSI devices to both the internal and external SCSI connectors on the same channel.
If you connect devices with different data transfer rates to the same SCSI channel, the speed of that channel will be limited to the maximum transfer rate of the slowest device. For example, if you connect both LVD SCSI devices and SE SCSI devices to the same SCSI channel, the data transfer rate for that channel will be limited to 40 MB/s, which is the maximum rate for SE SCSI.

To view a list of supported peripheral devices see the HP Ultra320 SCSI Host Bus Adapter Support Matrix:

http://docs.hp.com/en/netcom.html#SCSI%20Host%20Bus%20Adapters

Identifying Compatible SCSI Cables

Make all SCSI bus connections to the A7173A adapter with shielded, 68-pin cables (multimode, LVD or SE). The connectors on the cables are keyed for proper mating.

Figure 2-1 Identifying SCSI Cable Connectors

1	68-pin External HD (high density) SCSI cable connector
2	External Offset VHDCI (very high density cable interconnect) SCSI cable connector
3	Internal 50-pin Narrow SCSI cable connector
4	Internal 68-pin Wide SCSI cable connector

Connecting Internal Devices

The A7173A adapter has two internal 68 pin HD connectors, one for each SCSI channel. If you purchased your A7173A adapter as a factory-integrated controller (ordered on product option 0D1), any internal SCSI devices will be connected at the factory. If an internal SCSI device has been installed on one of the A7173A adapter’s SCSI channels, do not connect any devices to the external port for that channel.

Connecting External Devices

The A7173A adapter has two external 68 pin VHDCI connectors, one for each SCSI channel. External SCSI devices, may have 68 pin HD or VHDCI connectors. No SCSI cables are shipped with the A7173A adapter.




	NOTE: Auto termination is factory enabled on the A7173A adapter. External terminators can be ordered from HP, if necessary (order SCSI LVD/SE terminator: HP product number C2370A).

To connect external SCSI devices to the A7173A adapter:

Plug the 68-pin VHDCI connector on one end of a SCSI cable into an external connector on the A7173A adapter. Make sure the external connector you attach the SCSI cable to corresponds to the channel you want to connect the external device to.
Plug the 68-pin HD or VHDCI connector on the other end of the cable into the SCSI connector on the external SCSI device.
If you need to connect more than one external SCSI device to the adapter, “daisy chain” them together with shielded external SCSI cables.

When you have finished connecting the external devices, go to, “Setting the SCSI Parameters”.

Connecting SCSI Peripheral Devices

Technical documentation

» Table of Contents

» Glossary

» Index

Important Rules For Connecting SCSI Devices

Identifying Compatible SCSI Cables

Connecting Internal Devices

Connecting External Devices