NOTICE

NOTICE

SCSI Connections

Determining SCSI Bus Length

Determining SCSI Bus Length

This section helps you to determine the total length of the narrow, single- ended SCSI bus, the fast, wide differential SCSI bus and ultra, wide single- ended SCSI bus.

Narrow, Single-Ended SCSI Bus Length

Follow these instructions to calculate your total narrow, single-ended SCSI bus length (including the system unit, external SCSI devices, and SCSI interconnect cables) using Table 24:

1Find all of your external SCSI devices in the first column. In the third column, write the SCSI bus lengths (from the second column) that correspond to your de- vices.

In the third column, the length for the System Unit is already listed. This number must always be used for the system unit.

2In the fourth column, write down the lengths of the SCSI interconnect cables you are using for your installation. (Cable lengths are listed in subsection “Cables” in the section on “SCSI Restrictions.”

3Add all of the numbers in the third column and write that number on the subtotal line at the bottom of the column. Do the same for the fourth column.

4Add the subtotals together and write the total in the Total SCSI Bus Length box.

The total length of the narrow, single-ended SCSI bus must not exceed 6 meters (19.6 feet). If the number you write for Total SCSI Bus Length is greater than 6 meters (19.6 feet), try configuring your installation with shorter cables.

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