Appendix B

Internal cabling. You must include the amount of internal cabling in your calculations. See page 149 for information. If you have any other external devices on the bus (not installed inside your host computer), these devices may have some amount of internal SCSI cabling as well.

Termination

If the library or one of the tape drives is the last device on the SCSI bus, you must attach a terminator to the appropriate SCSI connector at the back of the library. The SCSI terminator must match the SCSI bus configuration (single-ended, LVD, or HVD; wide or narrow). Termination can be active or passive. If you are using Mammoth tape drives and your host can transfer data at more than 5 MB per second, use active termination. If you are using Eliant 820 tape drives, or if your host limits data transfer to 5 MB per second or less, use either active or passive termination. For best results on a single-ended bus, use active termination.

Note: Exabyte testing has shown that older passive termination does not provide rising edge transitions that are fast or clean enough at fast SCSI speeds.

SCSI IDs

Each device on the SCSI bus must have a unique ID. The host computer uses these IDs to identify each device. The SCSI ID also determines which device has priority when more than one device is trying to communicate with the host. The lower the ID, the lower the priority of the device.

Note: The SCSI ID does not depend on physical location. For example, the last device on a multi-device SCSI bus can have a SCSI ID of 2.

156

Exabyte 440 and Exabyte 480

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Exabyte 480, 440 manual Termination, Scsi IDs