Datalogic DP1200, Руководство по установке

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INSTALLATION
15
2
RS485 Half-Duplex Interface
The optocoupled RS485 half-duplex (3 wires + shield) interface is used for polled
communication protocols.
It can be used in a master/slave layout or for Multidrop connections with a Datalogic
Multiplexer, (see par. 2.5.4 and 2.5.5) exploiting a proprietary protocol based on
polled mode called MUX32 protocol, where a master device polls slave devices to
collect data.
The following pins of the spring clamp connector are used for RS485 half-duplex
communications:
Pin Name Function
*18, 21 RS485 transmitted/received data +
*19, 22 RTX485- RS485 transmitted/received data -
*20, 23 GNDRS485 RS485 Reference
* The signals on pins 18, 19 and 20 are repeated on pins 21, 22 and 23 to facilitate
network connections. In this way the network bus can enter and exit the DP1200
from different spring clamps but be physically connected together.
DP1200
MULTIPLEXER
RTX485-
RTX485-
GNDRS485
RS485REF
18, 21
19, 22
20, 23
Figure 13 - RS485 half-duplex connections