Siemens S5-135U/155U System Manual page 245

Wiring of a connecting cable for RTS/CTS flow control
CPU
Receiver
3
Transmitter
2
4
RTS
CTS
5
7
1
Housing, GND
Figure 5-19 Example of a Connecting Cable: CPU - CPU for RTS/CTS Flow Control
System Manual
C79000-G8576-C199-06
CPUs, Memory Cards, Memory Submodules, Interface Submodules
RxD
TxD
Shield
CPU
Transmitter
TxD
2
Receiver
3
RxD
4
RTS
5 CTS
7
1
Housing, GND
5-105