Installation Instructions
· 10 ·
EC3-1820V2NA
2.6 COM Port
1. This board provides two COM ports which support RS-232/RS-485/RS-422
mode. The COM1 is DB9 output; COM2 is 2×5Pin pin header output (pitch:
2.0mm). Their pin definitions are as follows:
Signal Name
Pin
RS-232
RS-422
RS-485
1 DCD# TXD- Data-
2 RXD TXD+ Data+
3 TXD RXD+ NC
4 DTR# RXD- NC
5 GND GND GND
6 DSR# NC
NC
7 RTS# NC
NC
8 CTS# NC
NC
COM1
COM2
9 RI# NC NC
Note: The COM port mode of COM1 and COM2 needs to be switched by BIOS
setup, and the setting path is Advanced\Com1&Com2 Mode Selection in the BIOS.
It is RS-232 mode by default in BIOS. Users can select RS-422 or RS-485 mode.
2. This motherboard provides two 2×5Pin pin header COM ports (pitch: 2.0mm).
Their pin definitions are as follows:
Pin
Signal Name
Pin
Signal Name
1 DCD# 2 RXD
3 TXD 4
DTR#
5 GND 6 DSR#
7 RTS# 8 CTS#
COM3 COM4
~
9 RI# 10
NA