3Com 3C16701A, 3C16703A, 3C16700A manual Straight-through Cable/Crossover Cable

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-through10BASE-T cable which is properly connected at both ends, and is not damaged. If the cable is connected to port 8, 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 9 below to compare the wiring of a straight-through and a crossover cable.

Figure 9 Straight-through Cable/Crossover Cable

Normal	Pin		Pin	Uplink	Normal	Pin		Pin	Normal
port				port	port				port
Rx+		1	1	Rx-	Rx+		1	1	Rx+
		2	2				2	2
Rx-				Rx+	Rx-				Rx-
		3	3				3	3
Tx+				Tx-	Tx+				Tx+
		4	4				4	4
		5	5				5	5
Tx-		6	6	Tx+	Tx-		6	6	Tx-
		7	7				7	7
		8	8				8	8

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