Digi TransPort WR21 - Page 53

Hardware features TransPort WR31 hardware features
Digi TransPort® Routers User Guide
53
RS422/RS485 pinout
Pin # Direction RS422/ RS485 Description
1 Out CTS- Clear To Send -
2 Out RD+ Receive Data +
3 In TD+ Transmit Data+
4 In RTS_B RTS- Ready To Send -
5 N/A GND Ground
6 Out RD- Receive Data -
7 In RTS+ Ready To Send +
8 Out CTS+ Clear To Send +
9 In TD- Transmit -
Notes
n For true RS485 mode (2-wire half-duplex mode), the TD+ and RD+ pair and TD- and RD- pair
should be connected together.
n The CTS and RTS signals are optional normally not needed for RS485.