DECrepeater 90TS Installation and Configuration
55
Connector Pin Assignments (Cont.)
Internal and External Crossover Configurations
A crossover function must be implemented in every twisted-pair link. The crossover
function (internal or external) allows the transmitter of one device to connect to the
receiver of the device at the other end of the twisted-pair link.
The following illustrations show the use of straight-through and crossover cables for
connecting internal and external crossover-type devices. The DECrepeater 90TS
uses crossover connectors.
Internal Crossover Configuration
3
4
5
6
7
8
1
2
3
4
5
6
7
8
1
2
8 MP
8 MP
Straight-through (=) cable
(BN26K or BN25G)
Device (MAU)
Crossover (X)
connector
Straight-through
connector
3
4
5
6
7
8
1
2
TX+
TX–
RX+
RX–
LKG-9153-94I
T
R
3
4
5
6
7
8
1
2
TX+
TX–
RX+
RX–
DECrepeater 90TS
T
R
8 MJ
8 MJ
External Crossover Configuration
Crossover (X)
cable (BN24F)
Crossover (X)
connector
Crossover (X)
connector
3
4
5
6
7
8
1
2
TX+
TX–
RX+
RX–
Device (Repeater)
LKG-9342-94I
T
R
3
4
5
6
7
8
1
2
3
4
5
6
7
8
1
2
8 MP
8 MP
3
4
5
6
7
8
1
2
TX+
TX–
RX+
RX–
DECrepeater 90TS
T
R
8 MJ
8 MJ
