WR703N – Wireless Serial Port

The following guide is what I’ve used (twice) to turn a WR703N into a wireless serial port for configuring Cisco network switches/routers. I have already installed OpenWRT onto it before this guide starts.

Tap the reset button on the side while inserting the power cable and the status light should flash blue fast. Set you PC’s IP address to 192.168.1.* (last octet cant be 1). Telnet to address and type the following:

Setup LAN Networking

uci set network.lan.ipaddr=<Ip Address>
uci set network.lan.gateway=<default gateway>
uci set network.lan.dns=<DNS-Server address>
 uci commit
/etc/init.d/network restart

Install Minicom and USB serial driver

opkg update
opkg install minicom
opkg install kmod-usb-serial-pl2303 <- This is a very common driver but you may need a different one, check online or with the manufacturer to see what you should use. If it’s correct you should see the following (or similar) when you type “dmesg”.

[  273.390000] pl2303 1-1:1.0: pl2303 converter detected
[  273.400000] usb 1-1: pl2303 converter now attached to ttyUSB0
[  273.410000] usbcore: registered new interface driver pl2303
[  273.410000] pl2303: Prolific PL2303 USB to serial adaptor driver

Setup Minicom

minicom -s
Serial port setup-> A ->”/dev/ttyUSB0″ -> Enter -> E -> C (Or what ever your likely to use the most) -> Enter -> F -> Enter -> “Modem and dialing” – clear all the strings -> Enter ->”Save setup as dfl” -> Exit (to Test), CTRL+A, Z, Q, Enter: To exit minicom.
vi /etc/profile, Add “minicom” to the bottom of the file. This will start minicom automatically when you telnet into it.

Use Picocom Instead of Minicom

opkg install picocom
vi /etc/profile, Add “picocom -b9600 -d8 -pn -fn /dev/ttyUSB0” to the bottom of the file.

Setup Wireless AP

Your setup will be different although the following will work as a standalone access point.

wifi detect > /etc/config/wireless
 vi /etc/config/wireless

Change: “option disabled 1” to “#option disabled 1” or remove the line.

Under “config wifi-iface” you need to change the wireless security settings.


config 'wifi-iface'
        option 'device'     'radio0'
        option 'network'    'lan'
        option 'mode'       'ap'
        option 'ssid'       'Wireless-Serial'
        option 'encryption' 'psk2'
        option 'key'        'ThisIsAReallyLongpassword'

/etc/init.d/network restart

“Using interface wlan0 with hwaddr ec:17:2f:f0:82:e8 and ssid ‘Wireless-Serial’ ”

When you connect to the wireless and telnet into the AP you should see similar to the following:

 === IMPORTANT ============================
Use ‘passwd’ to set your login password
this will disable telnet and enable SSH
——————————————BusyBox v1.19.4 (2012-08-07 17:43:30 UTC) built-in shell (ash)
Enter ‘help’ for a list of built-in commands._______                     ________        __
|       |.—–.—–.—–.|  |  |  |.—-.|  |_
|   –   ||  _  |  -__|     ||  |  |  ||   _||   _|
|_______||   __|_____|__|__||________||__|  |____|
|__| W I R E L E S S   F R E E D O M
ATTITUDE ADJUSTMENT (Bleeding Edge, r33035)
* 1/4 oz Vodka      Pour all ingredients into mixing
* 1/4 oz Gin        tin with ice, strain into glass.
* 1/4 oz Amaretto
* 1/4 oz Triple sec
* 1/4 oz Peach schnapps
* 1/4 oz Sour mix
* 1 splash Cranberry juice
picocom v1.7port is        : /dev/ttyUSB0
flowcontrol    : none
baudrate is    : 9600
parity is      : none
databits are   : 8
escape is      : C-a
local echo is  : no
noinit is      : no
noreset is     : no
nolock is      : no
send_cmd is    : sz -vv
receive_cmd is : rz -vv
imap is        :
omap is        :
emap is        : crcrlf,delbs,

Terminal ready

You will usually have to press Enter to get a response from the device on the other end of the serial cable at this pont.



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