US Robotics Courier USR3510, User Manual

Page: 154 / 162

Revision: 1.00 Copyright 2015 U.S. Robotics Corporation 154 | P a g e
Appendicies
Appendix A: DB9 Pinouts
The USR3520/USR803520 has two DB9 serial ports.
Terminal Port
The USR3520/803520 TERMINAL port is an RS232 DCE presented on a DB9 female connector using a
standard pinout.
RS232 output signal levels are nominally ±5v.
Modem Port
The USR3520/803520 MODEM port is an RS232 DTE presented on a DB9 male connector using a
standard pinout.
RS232 output signal levels are nominally ±5v.
DB9F Pin Symbol Description Direction
1 DCD Carrier Detect Output
2 TXD Transmit Data Output
3 RXD Receive Data Input
4 DTR Data Terminal Ready Input
5 GND Ground -
6 DSR Data Set Ready Output
7 CTS Clear To Send Input
8 RTS Request To Send Output
9 RI Ring Indicator Output
DB9M Pin Symbol Description Direction
1 DCD Carrier Detect Input
2 RXD Receive Data Input
3 TXD Transmit Data Output
4 DTR Data Terminal Ready Output
5 GND Ground -
6 DSR Data Set Ready Input
7 RTS Request To Send Output
8 CTS Clear To Send Input
9 RI Ring Indicator Input