14
GETTING TO KNOW YOUR MTC-2021
©Vecow MTC-2021 User Manual
2.2.13 Isolated Serial Port COM 5/ COM 6
COM 5 and COM 6 can be configured for RS-232, RS-422, or RS-485 with auto
flow control communication. Serial Port 2 default setting is RS-232, if you want
to use RS-422 or RS-485, you can find the setting in BIOS.
Serial
Port
Pin No.
RS-232
RS-422
(5-wire)
RS-422
(9-wire)
RS-485
(3-wire)
5,6
1
DCD
TXD-
TXD-
DATA-
2
RXD
TXD+
TXD+
DATA+
3
TXD
RXD+
RXD+
-----------
4
DTR
RXD-
RXD-
-----------
5
GND
GND
GND
GND
6
DSR
-----------
RTS-
-----------
7
RTS
-----------
RTS+
-----------
8
CTS
-----------
CTS+
-----------
9
RI
-----------
CTS-
-----------
The pin assignments are listed in the table as follow :
BIOS Setting
Function
COM 5 / COM 6
RS-232
RS-422 (5-wire)
RS-422 (9-wire)
RS-485
RS-485 w/z auto-flow control