INSTALLATION
15
2
2.3.2
RS485 Half-Duplex Main Interface
The RS485 half-duplex (3 wires + shield) interface is available for polled
communication protocols.
It can be used for multidrop connections with a Datalogic Multiplexer, (see Figure 13
and par. 2.6.2).
The following pins of the 25-pin connector are used for RS485 half-duplex
communication:
Pin Name
Function
2
Transmitted/received data (+)
4
RTX485-
Transmitted/received data (-)
7
SGND*
Main reference ground
*SGND is internally connected to the GND through a filtering circuit.
MATRIX
4
RTX485-
2
MULITPLEXER
RTX485-
7
SGND
RS485REF
Earth
Ground
1
SHIELD
Figure 13 - RS485 Half-duplex Connections
