SCSI ID Numbers
A.2 Determining SCSI ID Numbers
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SCSI ID 6 — SCSI-A controller
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SCSI ID 7 — Open
Rules for Setting SCSI ID Numbers
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You can have up to seven devices on one bus.
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Each device must have its own unique identifier.
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Two devices can have the same identifier only if they are on different buses.
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Each SCSI bus must be terminated.
Proper operation of the SCSI bus requires that you use high-quality,
properly configured cables and connectors to connect all devices. Digital
recommends that you use only Digital-supplied cable assemblies intended for
interconnecting SCSI devices. This ensures that the impedance characteristics,
signal propagation velocity, inductance, capacitance, cross-talk, grounding,
conductor pairing, and shielding meet the requirements for proper operation of
the bus.
Digital also recommends that all units on the SCSI bus be powered from a
common ac power source. Digital does not guarantee the proper operation of
any SCSI bus that uses cable assemblies not supplied by Digital, or that is not
configured in accordance with Digital’s recommendations.
A.3 Setting RRD42 ID Numbers
The RRD42 tabletop drive has a rear-panel pushbutton (see Figure 3–4) that
spins a wheel and advances a number. To set the device ID number, press the
button until the desired number appears.
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