Filter
Top Products
UNO-3074 User Manual 14
2.3.4
RS-232/422/485 Selection
COM3 and COM4
support 9-wire
RS-232, RS-422
and RS-485
interfaces.
The system detects
RS-422 or
RS-485 signals automatically in RS-422/
485 mode.
To select
between
RS-422/485 and
RS-232 for COM3, adjust JP4. To
select
between
RS-422/485 and
RS-232 for COM4, adjust JP5.
You can refer to figures below to set the JP4 and JP5.
Jumper
setting for RS-422/485 interface: (Default setting).
Figure 2.2:
RS-422/485 Jumper
Setting
Jumper
setting for RS-232
interface:
Figure 2.3:
RS-232 Jumper
Setting
2.3.5
RS-485 Auto Flow/RS-422 Master/Slave Selection
You can set the “Auto Flow
Control” mode of RS-485 or “Master/Slave”
mode of RS-422
by
using the SW2
DIP switch
for each
RS-422/485 port.
(Refer to Figure A.3 for location of SW2).
In RS-485,
if the switch
is
set to
“Auto”, the driver
automatically senses
the direction of the data
flow
and
switches the direction of
transmission.
Then no handshaking
is necessary.
In RS-422, if
DIP
switch is
set to
“On”,
the driver
is always
enabled,
and always in high or
low status.
Note:
Please refer to Appendix A.2 Figure A.3 for location
of JP4 and JP5 location