DB25 Serial
Loopback Plug Pinout


DB25 Female Connector

DB25 SERIAL LOOPBACK PLUG
PIN
FUNCTION
PIN
FUNCTION
1
GND
7
GND
2
TXD
3
RXD
4
RTS
5
CTS
4
RTS
8
DCD
6
DSR
11
TD-
6
DSR
20
DTR
6
DSR
22
RI
15
0
17
0
15
0
23
0
18
RD+
25
RD-