Datalogic DS8100A

CUSTOM CABLE ELECTRICAL CONNECTIONS
39
4
4.2.2 RS485 Full-Duplex Interface
The RS485 full-duplex (5 wires + shield) interface is used for non-polled communication
protocols in point-to-point connections over longer distances than those acceptable for
RS232 communications or in electrically noisy environments. The overall maximum cable
length should not exceed 1200 m (3940 ft).
The following pins of the 26-pin connector are used for RS485 full-duplex interface connection:
Pin
Name
Function
2
TX+
RS485 output (+)
3
RX+
RS485 input (+)
4
TX-
RS485 output (-)
5
RX-
RS485 input (-)
7
GND_ISO
Main signal ground
DS8100A
7
GND_ISO
TX485+
2
TX485-
4
RX485+
3
RX485-
5
+
SGND Main Isolated
USER INTERFACE
RX485
1
Earth
Ground
CHASSIS
-
+
TX485
-
Figure 47 - RS485 Full-Duplex Interface Connections
NOTE
For applications that do not use RX485 signals, do not leave these lines
floating but connect them to GND_ISO as shown below.
DS8100A
7
GND_ISO
TX485+
2
TX485-
4
RX485+
3
RX485-
5
+
SGND Main Isolated
USER INTERFACE
RX485
1
Earth
Ground
CHASSIS
-
Figure 48 - RS485 Full-duplex Connections using Only TX Signals