Avalue EBM-A50M - Manual (Page 10)

EBM-A50M Quick Installation Guide
10 EBM-A50M Quick Installation Guide
2.3.3 Serial port 1/ 2 - RS-232/ 422/ 485 mode selector (SW2)
In Serial Port 1 mode
RS-232 RS-422 RS-485
1 ON OFF OFF
2 OFF ON OFF
3 OFF OFF ON
In Serial Port 2 mode
RS-232 RS-422 RS-485
4 ON OFF OFF
5 OFF ON OFF
6 OFF OFF ON
2.3.4 Serial port 1/ 2 pin9 signal selector (JRI1/ JRI2)
* Default
Ring*
+5V
+12V JRI2
JRI1