Cabling Considerations
B.3.2
Device RJ-45 Wiring Considerations
You should give special consideration to the wiring scheme when connecting a device such as a terminal
to a MAXserver serial port. The MAXserver is considered a DTE device. If you want to connect to
another DTE device such as a terminal that is also DTE, you will need a crossover wiring scheme
somewhere in the cabling. (Communication between DTE-to-DTE devices requires a crossover.) When a
DCE device is connected to a MAXserver serial port, straight-through wiring is required.
To make a modular cable with a crossover, you need only crimp the RJ-45 connector in the same direction
at both ends. This crosses all wires in the cable. To make a modular straight-through cable, you need
only crimp the RJ-45 connector in opposite directions at both ends. Figure B-2 shows the crossover and
straight-through wiring schemes.
The crossover connects the MAXserver transmit data (XMT) line to the receive data (RCV) line of the
user DTE device. Similarly, the MAXserver receive data (RCV) line crosses over to the transmit data
(XMT) line of the user DTE device. The other signals are crossed over in a similar manner (see Figure B-
4).
Straight Through Cable
Crossover Cable
RJ-45
Connectors
RJ-45
Connectors
Figure B-2. Crossover and Straight-through Wiring Schemes
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