User's Manual
PN 8700-10 Help Hot Line (U.S. only): 1-800-530-9960 A-5
620003-0 Rev. B
A.6 DB-25 to DB-9 Null Modem Cable
A DB-25 male to DB-9 female Null modem cable is used to connect a 232 Port
Expander to a Unison Main Hub, or to connect a modem to the Main Hub when using
OpsConsole to monitor the system. Table A-3 lists the pinout of the cable for Unison
and Figure A-4 shows a diagram of its wiring.
Figure A-4 DB-25 Male to DB-9 Female Null Modem Modem Cable Diagram
Table A-3 DB-25 Male to DB-9 Female Null Modem Cable Pinout
25-Pin Signal 9-Pin Signal
20
2
3
6,8
7
5
4
DTR
TX
RX
DSR, DCD
GND
CTS
RTS
1, 6
2
3
4
5
7
8
DSR, DCD
RX
TX
DTR
GND
RTS
CTS
DB-25 Male
Connector
Pin
DB-9 Female
Connector
Pin
1
2
3
4
5
6
7
8
20
1
2
3
4
5
6
7
8
9