Allied Telesis AT-MR840TF - Manual (Page 29)

AT-MR820TR Hub Installation Guide
9
MDI/MDI-X Switch
The Media Dependent Interface/Media Dependent Interface Crossover (MDI/
MDI-X) switch is a slide switch that allows you to connect to either another hub
or to a workstation by converting Port 8 to an uplinkable port; thereby allowing
one hub to connect to another hub without requiring special crossover cables.
Figure 6 illustrates this switch; Table 3 defines the switch’s function.
Figure 6: MDI/MDI-X Slide Switch
Table 3: MDI/MDI-X Switch
MDI /MDI-X
Position
Function
MDI When in the MDI position (left), the port can be connected to
another hub using straight through twisted pair cabling. The MDI
position is a hub pinout which automatically swaps the TX and
RX pinouts so that they do not conflict with the TX and RX ports
at the other end of a straight-through cable.
MDI-X When in the MDI-X position (right), the port can be connected to
a workstation, node, or any other DTE (default).
1
2
3
6
1
2
3
6
1
2
3
6
1
2
3
6
MDI MDI-X
10BASE-FL BACKBONE PORT
X X X X X X X
10BASE-T NETWORK PORTS
POWER
8 7 6 5 4 3 2 1
1 2 3 6 1 2 3 6 1 2 3 6 1 2 3 6
MDI MDI-X RX TX RX TX LINK
MR840TF_Book Page 9 Tuesday, November 11, 1997 3:46 PM