Hewlett-Packard SureStore 125ex Optical Jukebox User's Guide - C1118-90000

OPERATING THIS JUKEBOX ON A SCSI BUS

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The lower eight data lines transfer commands and messages, allowing all devices, regardless of size, to co-exist on the

bus. However, data transfers and device addressing occur on the higher bits. Since a narrow device can't “see” the upper

8 data bits, that translates to it not being able to “see” wide devices with a SCSI ID of 8 or above. Remember the host

adapter is a device, so if you're mixing wide and narrow devices on the bus, your host adapter must be at an ID that all

devices can address.

If mixing narrow and wide devices is unavoidable, use the configuration shown in the following diagram. When look-

ing at the diagram note that, while this is a “legal” SCSI configuration, it is not a configuration that is recommended by

Hewlett-Packard. As a general rule, HP recommends that the jukebox be the only device on a bus. If there are multiple

devices on the bus, performance of one or all of the devices on the bus can be affected