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16
Port Status LED not lit for a 10BASE-T port that has a 
connection.
 There is a problem with this connection. 
Check that you are using a straight-through 10BASE-T cable 
which is properly connected at both ends, and is not 
damaged. If the cable is connected to port 4, ensure that 
the Uplink/Normal switch is set to Normal (out). Also check 
that the equipment being connected to the hub is powered 
on and operating correctly. Refer to Figure 6 below to 
compare the wiring of a straight-through and a crossover 
cable.
Figure 6   Straight-through Cable/Crossover Cable
Pins 4, 5, 7 and 8 are not used
Straight-through
Crossover
Pins 4, 5, 7 and 8 are not used
TxD+
TxD-
RxD+
RxD-
1
2
3
6
1
2
3
6
TxD+
TxD-
RxD+
RxD-
TxD+
TxD-
RxD+
RxD-
1
2
3
6
1
2
3
6
TxD+
TxD-
RxD+
RxD-
3C16700.book  Page 16  Tuesday, July 13, 1999  9:59 AM