Moxa V2403-C7-W-T [19/90] Serial port operation mode

V2403 Series Linux Software Managing Communications

3-4

Serial Port Operation Mode

The V2403-LX computer has 4 serial ports named COM1, COM2, COM3, and COM4. The ports support RS-232,

RS-422, 2-wire RS-485, and 4-wire RS-485 operation modes with baudrate settings up to 921600 bps.

By default, the serial interface is set to RS-232. You can use the setinterface command to change the serial

port operation mode, as indicated below:

setinterface device-node [interface-no]

device

-node

/dev/tty

M0 to /dev/ttyM3

interface

-no

set to RS232 interface

set to RS485

-2WIRES interface

set to RS422 interface

set to RS485

-4WIRES interface

For example, use the following commands to set /dev/ttyM0 to RS-422:

root@Moxa:/home/moxa# setinterface /dev/ttyM0 2

root@Moxa:/home/moxa# setinterface /dev/ttyM0

Now setting is RS422 interface.

DNS Client

The V2403-LX supports DNS client (but not DNS server). To set up DNS client, you need to edit three

configuration files: /etc/hostname, /etc/resolv.conf, and /etc/nsswitch.conf.

/etc/hostname

1. Edit /etc/hostname:

moxa@MOXA:~# sudo vi /etc/hostname

Moxa

2. Re-configure the hostname.

root@Moxa:~# /etc/init.d/hostname.sh start

3. Check the new hostname.

root@Moxa:~# hostname

/etc/resolv.conf

This is the most important file that you need to edit when using DNS. For example, before using # ntpdate

time.stdtime.gov.tw to update the system time, you will need to add the DNS server address to the file. Ask

your network administrator which DNS server address you should use. The DNS server’s IP address is specified

with the nameserver command. For example, add the following line to /etc/resolv.conf (assuming the DNS

server’s IP address is 168.95.1.1):