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Serial Device USB to RS-232/422/485 Converter
2 RX 3 TX
3 TX 2 RX
5 GND 5 GND
7 RTS 8 CTS
8 CTS 7 RTS
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RS-422 Pin Assignment
The pin assignment scheme for a 4-pin RS-422 is given below.
RS-422: PIN 1: T+ PIN 2: T- PIN 3: R+ PIN 4: R-
RS-485: PIN 1: D+ PIN 2: D-
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RS-422 Wiring Diagram
Serial Device
USB to RS-232/422/485 Converter
R- 2 T-
R+ 1 T+
T- 4 R-
T+ 3 R+
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RS-485 Wiring Diagram
Serial Device
USB to RS-232/422/485 Converter
D- 2 D-
D+ 1 D+
1 2 3 4
(Flow Control)
(Flow Control)