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BOCAHUB-24Plus
4.3 Crossover Function
Two Ethernet 10BASE-T devices can communicate
only if the transmitter on one device is connected to
the receiver of the other device. The 10BASE-T
specification suggests that the crossover function be
implemented in the concentrator itself. On the
BOCAHUB-24 Plus, this crossover function is
implemented in all ports. However, the last port (24x)
is crossed to simplify installation when cascading
concentrators. This port is labelled “24x” and located
on the front of the BOCAHUB-24 Plus below the Boca
Research logo. WARNING: do NOT use port 24 and
24x. Connect only one of these ports.
When a twisted-pair port labelled with an “X” is
connected to a device which does not support the
crossover function, “straight-through” wiring can be
used (see 4.4).
When connecting two identical twisted-pair ports
(that is, ports that either BOTH support or NOT
support the crossover function), a crossover must be
implemented in the wiring (see 4.5).
