Pinouts and Cabling Diagrams 406
EIA-232 Cabling Diagrams
Modem DB25 Connector
The following diagrams show how a standard straight through cable should be configured when
connecting to a DB25 modem.

DB25 Male

RJ45

This cabling table does NOT apply to SCS48C/SCS32C/SCS16C/SCS8C (Sun/Cisco),
SDS32C/SDS16C/SDS8C (Electrical Utility) or medical unit models.
IOLAN DS1
DB25 (DTE)
Modem DB25
(DCE)
2 (TxD) 2 (RxD)
3 (RxD) 3 (TxD)
4 (RTS) 4 (CTS)
5 (CTS) 5 (RTS)
6 (DSR) 6 (DSR)
7 (GND) 7 (GND)
8 (DCD) 8 (DCD)
20 (DTR) 20 (DTR)
IOLAN RJ45
Modem DB25
(DCE)
10-pin 8-pin
2(DCD) 18 (DCD)
3(RTS) 24 (CTS)
4(DSR) 36 (DSR)
5(TxD) 42 (RxD)
6(RxD) 53 (TxD)
7(GND) 67 (GND)
8 (CTS) 7 5 (RTS)
9(DTR) 820 (DTR)