HP 28642A manual Terminate the Scsi Bus

Set switchesor jumpers on your device(s) asappropriate. Be sure each SCSI device hasa unique SCSI address.

For optimum noise immunity, any device that suppliestermination power should be enabled to do so. If at least two devicessupply termination power, Locatethem at eachend of the SCSIbus.

Connect the device end of the SCSIport cable (50-pin, low-density SCSI connector) to the first SCSI device. If applicable, connect subsequentdevices. The connection method is often called “daisy-chaining”.Refer to your device manualsfor proper connection to a SCSIbus.

Use active SCSI terminators.

Use HP-supplied SCSIcables.

Minimize the SCSIbus length. However, do not usedevice-to-device cablesthat are lessthan 0.5 meter.

Do not exceedthe maximum single-endedSCSIbus length of 6 meters,which includes the SCSI port cable a& any internal devicecabling. (The SCSI/parallel adapter hasan internal SCSI cable length of 0.1meter.)

Do not exceed the maximum number of devices supported for your particular system.

Terminate the SCSI Bus

Unless the SCSIbus is properly terminated, the bus will not operate reliably. Terminators provide matching impedance and bias the bus signatlines.

This product includes an external SCSI bus terminator assembly,part number 1252-3920,to terminate the peripheral end of the SCSI bus. The terminator assemblycontains a SO-pin, low density, male connector. Adapting connectorscan be usedto accommodateother types of SCSIconnectors. Consult HP for availability,

As illustrated in figure l-11, install the terminator on the end of the SCSIbus (opposite the SCSI/parallel adapter).

l-20 lndalling the Adapter