MATRIX 400™ REFERENCE MANUAL
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4.2.3 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.
CBX100/500 Function
RTX+ RS485 Receive/Transmit Data +
RTX- RS485 Receive/Transmit Data -
SGND Signal Ground
RTX485+
SGND RTX485-
USER INTERFACE
SGND RTX+
RTX-
READER
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
VisiSet™ utility or by the Host Programming Mode.
Figure 55 shows a multidrop configuration with Matrix 400™ readers connected to a
Multiplexer.
CAUTION
This is an example of multidrop wiring. Consult the multiplexer manual for
complete wiring instructions.