Filter
Top Products
[a]
[b)
Fig. 2.4 SCSI termination
on
the rear of the LS-10E
scanner
20
Terminaison SCSI iI I'arriere
du
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