UNO-1251G User Manual
20
A.3
Switch setting of RS-485 Serial Port (COM1) &
RS-4222/485 Serial Port (COM2)
A.4
RS-232 Serial Port (COM3)
SW
SW7
Description
COM1 RS485; COM2 RS422/485 termination resistor setting
COM2 RS422/485 mode setting
Default
1.
Termination
resistor
ON
2. COM2 RS-422 mode (contact to Pin 5, 6, 7, 8)
Termination resistor ON
COM1
RS485:
Contact
to
Pin
8,
COM2
RS485:
Contact
to
Pin
7,
COM2
RS422
Tx:
Contact
to
Pin
7,
COM2
RS422
Rx:
Contact
to
Pin
6
(if
switch
to
termination
resistor
OFF,
Contact
to
Pin
1,
2
,
3)
RS-422 master mode
Contact
to
Pin
5
(if switch to RS-422 slave mode/RS-485,
contact to Pin4)
Table A.3: Connectors and Jumpers
Pin Description
1
DCD
2
RxD
3
TxD
4
DTR
5
GND
6
DSR
7
RTS
8
CTS
9
RI