LSI LSIU40SE Value Line, Руководство пользователя

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2-24 Installing the LSIU40SE
2.2.10.1 Channel Switches
When connecting another LSIU40SE, you must turn on the switch for the
connector used on one or both of the boards. Please refer to
Figure 2.18 ,
and the next two paragraphs, to determine the correct switch setting.
Four switches for each channel provide cable detection simulation and
forced upper line termination. Switch one simulates a device on the
internal 50-pin connector, switch two simulates a device on the internal
68-pin connector, switch three forces the upper SCSI line terminator to
stay on, and switch four simulates a device on the external 68-pin
connector.
When LSIU40SE is in the middle of a bus using only one connector, then
switch Int68 and Ext68 (switches 2 and 4) for that bus are on. This forces
the terminators for that bus to be disabled.