Product overview 
 
Embedded PC  39 
CX1020-N030/40 connections 
 
 
 
The CX1020-N030 system interface features two RS232 interfaces, COM1 and COM2 (9 pin Sub-D plug connector). 
If there is need for more than two serial interfaces two further RS232 interfaces, COM3 and COM4 (9 pin Sub-D plug 
connector) can be added to the system via the system interface CX1020-N40. The maximum baud rate on all 
channels is 115 kBit. The pin assignment for all interfaces is equal and described below. The interface parameter can 
be set in the operating system or in the PLC program.  
RS232 COM interface (connector): 
 
Pin assignment COM interface: 
PIN  Signal  Type  Description 
1  DCD  Signal in  Data Carrier Detected 
2  RxD  Signal in  Receive Data 
3  TxD  Signal out  Transmit Data 
4  DTR  Signal out  Data Terminal Ready 
5 GND  Ground  Ground 
6  DSR  Signal in  Dataset Ready 
7  RTS  Signal out  Request to Send 
8  CTS  Signal in  Clear to Send 
9  RI  Signal in  Ring Indicator 
 
Note   
 
 
 
The system interface CX1020-N30 can only be used instead and not simultaneously with system 
interface CX1020-N031. 
The system interface CX1020-N40 can only be used instead and not simultaneously with system 
interface CX1020-N041.