Digital Equipment ChannelWorks, Network Installer Manual

Page: 69 / 90

Cables for Serial Devices A-3
Figure A-1 Null Modem Cable Wiring
DB 9
Connector
DB 9
Connector
DCD 1
RXD 2
TXD 3
DTR 4
GND 5
DSR 6
RTS 7
CTS 8
RI 9
1 DCD
2 RXD
3 TXD
4 DTR
5 GND
6 DSR
7 RTS
8 CTS
9 RI
•
•
N/C
N/C
A null modem cable also disables certain features of a peripheral device by moving
jumper wires from one pin to another on the same connector. Figure A-1 shows pins 1
and 6 connected and then connected to pin 4.
A cable wired like the one shown in Figure A-1 will properly connect a PC to the
ChannelWorks Bridge.
If you have a PC without a 9-pin serial port, consult the service manual of the PC to
determine which pins are active. You will have to wire the cable connectors according
to the needs of both the PC and the ChannelWorks Bridge serial ports.