
DB-9 to DB-9 Null Modem Cable
A-4
InterReach Unison Installation, Operation, and Reference Manual
CONFIDENTIAL
D-620003-0-20 Rev J
A.5
DB-9 to DB-9 Null Modem Cable
Use a DB-9 female to DB-9 female null modem cable to connect the AdminManager
PC to a Unison Main Hub. A cable is included with AdminManager. Table A-2 lists
the cable pinout and Figure A-3 shows a diagram of its wiring.
Figure A-3
DB-9 Female to DB-9 Female Null Modem Cable Diagram
Table A-2
DB-9 Female to DB-9 Female Null Modem Cable Pinout
From
Signal
To
Signal
P1-4
DTR
P2-6, P2-1
DSR, DCD
P1-6
DSR
P1-1, P2-4
DCD, DTR
P1-3
TXD
P2-2
RXD
P1-2
RXD
P2-3
TXD
P1-5
GND
P2-5
GND
P1-7
RTS
P2-8
CTS
P1-8
CTS
P2-7
RTS
P1-9
N/C
N/C
N/C
Note that for each DB-9 connector, pins 1 and 6 are tied together and sent to pin 4
of the opposite connector, providing the required handshake signals.
DB-9
Connector
Pin
DB-9
Connector
Pin
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9