Proface APL3000B - Node Box PC - Manual (Page 7)

7
Serial Mode Select Switches (SW4 to SW10) operate as shown in the circuit diagram below.
5
Switches the TX
termination
resistance ON/
OFF
Inserts
termination
resistance of
220
Ω between
TXA and TXB.
No termination OFF ON
ON/
OFF
*2
6
Switches the RX
termination
resistance ON/
OFF
Inserts
termination
resistance of
220
Ω between
RXA and RXB.
No termination OFF ON
ON/
OFF
*2
7
Switches the
shorting of TXA
and RXA ON/OFF Shorts TXA and
RXA
(RS-485 mode)
No shorting
(RS-422 mode)
OFF OFF ON
8
Switches the
shorting of TXB
and RXB ON/OFF Shorts TXB and
RXB
(RS-485 mode)
No shorting
(RS-422 mode)
OFF OFF ON
9
RTS Automatic
control mode
(enabled only
when RS-485
mode)
The data is
automatically
controlled via the
RTS signal. The data is not
automatically
controlled via
the RTS signal. OFF OFF
ON/
OFF
*3
10 OFF OFF
ON/
OFF
*3
Table 2) Serial Mode Select Switches
*1 Be sure to keep the settings, "OFF" for RS-422 or RS-485.
*2 If you use the termination resistance, base your settings on the connection specifications.
*3 To control TX output driver via RTS automatically, set ON. Be sure to set SW No.4 OFF.
Not to control TX output driver via RTS automatically, set OFF. Be sure to set SW No.4 ON.
Switch
No.
Description ON OFF
RS-
232C
RS-
422
RS-
485
TXD
RTS
SW4
SW9
SW10
SW5
SW7
SW6
SW8
TXA
TXB
RXA
RXB
RTS Automatic
control
COM2