Siemens SIMATIC TIWAY 1 - Manual (Page 63)

CONFIGURING THE HOST COMPUTER PORT
UNILINK HOST ADAPTER 3–5
USER MANUAL
The IBM PC/AT r uses a 9-pin “D” connector for its serial interface port. A null
modem cable diagram for the IBM PC/AT port is shown in Figure 3–5.
6
1
9
5
14
25
1
13
GND
DTR
SD
RD
DCD
RI
CTS
RTS
DSR
TxD
RxD
RTS
CTS
DSR
GND
DCD
IBM PC/AT 9–Pin UNILINK Host Adapter 25–Pin
Figure 3–5 IBM PC/AT 9-Pin Null Modem Cable Diagram