Pin Assignments
C-2
893-743-A
10BASE-T Ports
Table C-2 shows the RJ-45 pin assignments for the 10BASE-T ports on the
Model 281xSA hub.
RS-232 Port
Table C-3 shows the pin assignments for the RS-232 port on the Model 281xSA
hub.
Table C-2. 10BASE-T port pin assignments (RJ-45 jack)
Connector
Pin#
MDI Signal (Function)
MDI-X Signal (Function)
1
TD + (Transmit to UTP wire)
RD + (Receive from UTP wire)
2
TD - (Transmit to UTP wire)
RD - (Receive from UTP wire)
3
RD + (Receive from UTP wire)
TD + (Transmit to UTP wire)
4
Not used by 10BASE-T
Not used by 10BASE-T
5
Not used by 10BASE-T
Not used by 10BASE-T
6
RD - (Receive from UTP wire)
TD - (Transmit to UTP wire)
7
Not used by 10BASE-T
Not used by 10BASE-T
8
Not used by 10BASE-T
Not used by 10BASE-T
Table C-3. RS-232 interface port pin assignments (DB-25 plug)
Connector
Pin # Function
Direction
2
Transmit data
from Model 281xSA hub
3
Receive data
to Model 281xSA hub
4
Request to send
from Model 281xSA hub
5
Clear to send
to Model 281xSA hub
6
Data set ready
to Model 281xSA hub
7
Signal ground
8
Carrier detect
to Model 281xSA hub
20
Data terminal ready
from Model 281xSA hub
22
Ring indicator
to Model 281xSA hub
12345678
1882.7.9.5
1
14
25
13
2206.5