INSTALLATION

2

 

RS485 Half-Duplex Interface

The RS485 half-duplex (3 wires + shield) interface is used for polled communication protocols.

It can be used for Multidrop connections with a Datalogic Multiplexer, (see par. 2.6.3 and 2.6.4) exploiting a proprietary protocol based on polled mode called MUX32 protocol, where a master device polls slave devices to collect data.

The connector pinout follows:

 

Pin

 

Name

Function

 

 

 

 

 

 

 

 

 

6

 

 

RTX485+

RS485 transmit/receive data +

2

 

 

RTX485-

RS485 transmit/receive data -

4

 

 

SGND

signal ground

 

 

 

 

 

 

 

 

 

 

DS1500

 

 

 

 

 

MULTIPLEXER

 

 

 

 

 

6

RTX485 +

 

 

 

 

RTX485 +

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

2

RTX485 -

 

 

 

 

RTX485 -

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

4

SGND

 

 

 

 

RS485REF

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

13

 

 

 

 

 

 

 

SHIELD

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Earth Ground

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Figure 9 - RS485 Half-duplex Connections

This interface is forced by software when the protocol selected is MUX32 protocol.

In a Multiplexer layout or for slaves, the Multidrop address must also be set via the serial channel by the WinHost utility or by ESC sequences.

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