Allied Telesis AT-MR840TF - Manual (Page 41)

AT-MR820TF Hub Installation Guide
21
Straight-through Cable Wiring
If the twisted-pair link segment is to join two ports on a switch, and only one of
the ports has an internal crossover, the two pairs of wires must be
straight-through, as shown in Table 8.
Table 8: Straight-through Cable RJ45 Pin Assignments
Crossover Cable Wiring
Two AT-MR840TFs can communicate only if the transmitter on one unit is
connected to the receiver on the other unit. This reversal, or crossover function,
can be implemented either in the wiring or in the device itself (MDI-MDI-X)
switch. When connecting AT-MR840TFs, a crossover must be implemented in
the wiring. Refer to Table 9 for crossover pin assignments.
Table 9: Crossover Cable RJ45 Pin Assignments
Hub Device
1 (TX+) 1 (TX+)
2 (TX-) 2 (TX-)
3 (RX+) 3 (RX+)
6 (RX-) 6 (RX-)
AT-MR840TF AT-MR840TF
1 (TX+) 3 (RX+)
2 (TX-) 6 (RX-)
3 (RX+) 1 (TX+)
6 (RX-) 2 (TX-)
MR840TF_Book Page 21 Tuesday, November 11, 1997 3:46 PM