DS8100
30
2
2.6.3 RS485
Master/Slave
The RS485 Master/Slave connection is used to collect data from several scanners to
build either an omni-directional or multi-sided reading system; one Master and, for most
applications, up to 2 Slaves can be connected together. For applications requiring more
than 2 Slaves contact the Datalogic Technical Support team.
The Master and Slave scanners are connected together using RS485 half-duplex on
the auxiliary serial interface.
The Master scanner is also connected to either a Host or a Multiplexer on the main
serial interface. The possible main interface type selections are RS232 or RS485 full-
duplex for Host connections or RS485 half-duplex for Multiplexer connections (see
“Main Interface Selection” in par. 2.2.1).
For the Slave scanners the Multidrop Address Selection can be made using the DIP
switch. The addresses must be consecutive and not include zero for hardware
configuration, or be selected in software (in this case the DIP switch address must be
zero for each Slave). See par. 2.2.2.
NOTE
The main serial port of the Slave scanners can be used for
configuration. The termination resistors of the RS485 bus must not
be installed.
Single P.S.
The P.S. signal is unique to the system; there is a single reading phase and a single
message from the master scanner to the Host.
Presence sensor
3
Auxiliary serial interface: RS485 half-duplex
2
Main serial interface
1
HOST
PC or PLC
RS232
RS485 full-duplex
MULTIPLEXER
MX4000
RS485 half-duplex
Slave
Master
2
Slave
DS8100
DS8100
DS8100
1
3
Figure 33 - Master-slave Single P.S. layout
