25-PIN CABLE ELECTRICAL CONNECTIONS
63
5
5.2.3 RS485
Half-Duplex
Interface
NOTE
This interface is provided for backward compatibility. We recommend using
the more efficient ID-NET™ network for Master/Slave or Multiplexer layouts.
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. 6.5) 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:
25-pin
Name
Function
2
RTX+
RS485 Receive/Transmit Data +
4
RTX-
RS485 Receive/Transmit Data -
7 GND
Ground
RTX+
2
RTX-
4
RTX485 -
7
GND
MULTIPLEXER
RS485REF
DS4800
1
Chassis
Figure 54 - RS485 Half-duplex Connections
This interface is forced by software when the protocol selected is MUX32 protocol.
In a Multiplexer layout, the Multidrop address must also be set via serial channel by the
Genius™ utility or by the Host Programming Mode.
Figure 55 shows a multidrop configuration with DS4800 scanners connected to a Multiplexer.
CAUTION
This is an example of multidrop wiring. Consult the multiplexer manual for
complete wiring instructions.
