[a]

[b)

Fig. 2.4 SCSI termination on the rear of the LS-10E scanner

Terminaison SCSI iI I'arrieredu scanner LS-10E

SCSI-AbschluB an der Ruckseite des

Scanners LS-10E

2-3 Terminating the SCSI Chain

The SCSI chain is an electrical bus connecting two or more devices. It is critical that this bus be correctly terminated for the SCSI peripherals to work properly.

Termination is an electronics term that applies to the impedance found at both ends of the bus. The electrical signals on the SCSI bus are changing rapidly between their digital " on " and " off" states . To minimize noise, a terminator is placed at each end of the bus . The effects of this termination may be subtle, but are critical.

Warnlngl

Incorrect SCSI termination can cause unpredictable errors.

Typically, the computer sits as one end of the SCSI bus. Assuming this is the case, the SCSI controller in the computer has to be terminated .

If another SCSI peripheral shares this SCSI bus, it also has to be terminated . If additional SCSI devices sit on the bus in between the two end SCSI devices, these devices can NOT be terminated . Only two terminated devices can reside on the SCSI bus, one at each end.

Terminating an LS-10E

The LS-10E scanner box is configured with two 50-pin SCSI connectors on the rear of the LS-10E unit as shown in Figure 2.4. Install the standard 50-pin SCSI terminator onto the bottom connector if termination is desired. If the LS-10E sits in the center of a SCSI chain , then by necessity, the bottom connector will be used for a SCSI terminator.

[a]SCSI connectors

[b]TERM . PWR. switch

[c]SCSI terminator

Term. Power Switch

If the terminator-power is supplied by the other connected peripherals, always turn off the " TERM . PWR " switch on the rear panel.

If it is not so supplied, always turn on the switch . ON: Supplies SCSI terminator-power

OFF: Stops supplying SCSI terminator-power

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Nikon instruction manual Terminating the Scsi Chain, Terminating an LS-10E, Term. Power Switch