
Document Reference No.: ES_000086
ES-R-2x01B-M RS-232 to RS-422/RS-485 Converters Manual
Version 1.0
Clearance No.: ES
#
42
©2010 - 2011 EasySYNC Ltd.
11
Wiring diagrams
The following diagram shows an RS-422 full-duplex bus. The ES-R-2x01B-M converters have a built-in
resistor for terminating their RxD ± input, which can be enabled using a jumper. The Tx ± lines which are
outputs from the ES-R-2x01B-M are terminated at the receiver at the other end of the bus as shown.
Twisted pair wires are required for each signal pair.
Figure 4
RS-422 4 Wire Full Duplex
The following diagram shows an RS-422 full-duplex bus with handshaking signals connected. The ES-R-
2x01B-M converters have built-in resistors for terminating their RxD ± and CTS ± inputs, which can be
enabled using jumpers. The TxD ± and RTS ± lines which are outputs from the ES-R-2x01B-M are
terminated at the receiver at the other end of the bus as shown. Twisted pair wires are required for each
signal pair.
Figure 5
RS-422 with handshaking signals connected
RS-422 Device
ES-R-2x01B-M
RxD+
TxD+
RxD-
TxD-
TxD+
RxD+
TxD-
RxD-
GND
GND
CTS+
RTS+
CTS-
RTS-
RTS+
CTS+
RTS-
CTS-
RS-422 Device
ES-R-2x01B-M
RxD+
TxD+
RxD-
TxD-
TxD+
RxD+
TxD-
RxD-
GND
GND