In Luci click Network, then WAN, then select UMTS instead of pppoe,static dynamic orwhatever you use now
there change APN to your match your provider and optionally username and pass (only if needed by your provider - usually not)
then change /dev/ttyUSB2 to /dev/ttyUSB0 if you use a Huawei modem.
But the main issue is that your modem to be recongnised and switched.
further reading here: http://wiki.openwrt.org/doc/recipes/3gdongle

(Last edited by maurer on 13 Oct 2011, 09:32)

Thanks, I have built the latest trunk with nearly full functions on my 703n now.
I heard some guys even built samba support to the firmware to share the USB key/disk connected to the router.
I've tried to add USB support, it can mount USB disk now, but no space left for samba package... :-(

if you're good with console - you can skip luci - it will save you the needed space.

I have prepared a new image, but I think the internal IP address has been messed up, the LED keeps blinking. No matter how long I pressed the reset button during power up, the LED keeps blinking.     I note that if I pressed the button for less than 3 seconds during power up, the LED would blink at least double the rate of the "restorefactory".  I guess it is somewhere at the u-boot, looking for image at TFTP server.  Anybody knows where is the IP address and the name of the image file required?

try with a serial console

When I get into the fast-blinking mode, if I set my network settings to 192.168.1.4 static IP I can ping the router on 192.168.1.1. But what image should I use with tftp? It does not seem to accept anything. Maybe it is not running a TFTP server but something else? I also broke mine messing with DHCP settings and can't get in now.

Thanks for your suggestion.

I am a frequent serial console user. Unfortunately, I am not mechanical skillful, I don't know how to open the cover without permanent damaging the blue cover.  Besides, Atheros has very weird design at their serial console. The Tx pin must be pulled low (or high, I forgot) at WR841N, otherwise, many garbage characters pop up.  I reported to Juhosg two years and he also noticed that.

Any suggestion for painless cover opening for the 703n?

try opening the blue cover with a very thin blade ( i opened mine with a cutter's blade )

Two good news to me, one bad news to me and one bad news to all future WR703n users.
1. I can open the blue cover with minimum damage. Of course, you cannot expect opening a screw-less box without little brute force.
2. I can adhere a 0.1" header to the serial console.
3. New 703n user cannot solder a header to the box. I use heat-conductive paste (for cell phone repairing) to adhere the header to the board. v1.2 box does not have through hole at the TP-out and TP-in. Just a small pad, little bit bigger than a resistor soldering pad.
4. I screw-up the network interface for my image. I cannot download a new image through the network interface, both wired and wireless.

Anybody knows how to break the u-boot of the 703n for booting?  ESC, F1, ENTER are tried.

If the serial console can take the image, maybe possible, but I don't know how to do that.

(Last edited by r32190 on 19 Oct 2011, 04:03)

Oh, good news!  Fast blinking mode is the OpenWrt fail-safe mode!!
You can telnet to the box at 192.168.1.1 !!!

Nice find! I didn't try something like telnet. So does it have any programs to update firmware with?

Tried wget and scp, both failed. "bad port spec" is encountered at scp, and similar for wget.  Finally, using nc (netcat) to pipe the file into the /tmp folder, use mtd to flash the file, unbrick the box successfully.

(Last edited by r32190 on 19 Oct 2011, 10:52)

Wow, that is a very cool method. Thanks a lot for this.

Right.  Should be useful for future 703n user. My serial console is broken, it is worthy to spend half an hour to do it because it indicated to me "fast blinking mode" is the fail-safe.  The console for v1.2 box is very difficult to build, so I leave a more complete note here for un-brick without serial console:

1. Press the reset during power up for about 4 to 5 seconds.
2. The LED will start to blink within a second. If the blinking rate is normal, the fail-safe mode is  NOT entered, repeat step 1. Fast blinking will be 4-5 beat per second.
3. Telnet to the box at 192.168.1.1  . No DHCP, so you need to manually configure your PC to the 192.168.1.2 or other IP at that subnet.
4. Get a "squash-sysupgrade.bin" from the snapshot or the formal backfire in future. Get a nc (netcat) for your PC. I prefer Linux because my virus scanner does not like the Windows "nc".
5. At PC: cat XXX.bin | nc -l 3333     <- 3333 is an arbitrary port, any free port would be fine, something higher than 1000.
6. At the telnet dialog:   nc 192.168.1.2 3333 > /tmp/703.bin      Copy would be finished within 5 seconds. Too short or long is no good or meaning failure.
7. Telnet dialog:
    cd /tmp
    mtd -r write 703.bin firmware                  Press "w" repeatedly (or there may be better way) until the box reboot.

8. Cross your finger.

(Last edited by r32190 on 20 Oct 2011, 08:34)

is there stock english firmware for this router?

i cant get the 3g to work on this thing with wrt. it doesnt recognize it. i tried 2 different brands zte and huawei. i changed the 2 to a 0 and all. not sseeing anything. did anyone find anything about this problem ?>

hi all,
I discovered with that both 3g usb modems K3520 -Z and -H (made by huawei and zte) don't get enough electrical power do dial or to maintain a connection.
tried in different sites  - so the 3g signal was ok and with 2 different carrier sims inserted.
also tried it with 2 different 703n - so it's a general issue affecting all the v1.2.
when first power the router it get a connection and it drops it 2 seconds after and then there is only  no carrier message in syslog.
So faramisimo - you might have the same problem - what modems did you try?
do you have all the correct kernel modules installed?

(Last edited by maurer on 20 Oct 2011, 11:17)

i tested it with a zte and a huawei. with this firmware that was posted by you. http://freestorage.ro/rqvt0evrix3j
i am guessing that would be the same problem i am having.

edit...
i just messed up the settings of my router so bad the dhcp is dead. how can i reset the router? the reset button doesnt seem to work i cannot connect to it with a lan cable :S

(Last edited by faramisimo on 20 Oct 2011, 13:11)

up five posts

i amtrying that i am unable to connect with ethernet for some reason. changed the ip address and all.. i can connect with windows but i dont know how to use the cat thing on windows. so i got half of the process working on each system but not both on one.

i got nc to work on windows but now its giving this error " cat: forward host lookup failed: h_errno 11004: NO_DATA " no matter what port i use...
is there something special i should do ?

(Last edited by faramisimo on 20 Oct 2011, 15:18)

after telnet to router:
mtd -r erase rootfs_data

1. held the reset button at boot ( router ) the blue light starts to flash on off quickly
done

2. Telnet to the box at 192.168.1.1  . No DHCP, so you need to manually configure your PC to the 192.168.1.2 or other IP at that subnet.
done

3. Get a "squash-sysupgrade.bin" from the snapshot or the formal backfire in future. Get a nc (netcat) for your PC. I prefer Linux because my virus scanner does not like the Windows "nc".
nc is working i have a firmware on c:\rw.bin

4. At PC: cat c:\rw.bin | nc -l 2001 i am not sure how to check for open ports but i tested man ports
i get the following error.

"C:\nc>nc
Cmd line: cat c:\wr.bin | nc -l 2001
cat: forward host lookup failed: h_errno 11004: NO_DATA"

or if i use this command line it looks like this
C:\nc>nc cat wr.bin | nc -l 192.168.1.1 2323
local listen fuxored: INVAL
cat: forward host lookup failed: h_errno 11004: NO_DATA

i am able to telnet and all so i've done something right. anyone has any ideas?

(Last edited by faramisimo on 21 Oct 2011, 00:13)

Are you using Windows?  I suggest you use native Linux (or Live CD). It is proven.
I am using Ubuntu at Vmware player within a Windows at my office with a USB network card to do testing during office hour.  Apparently a real Linux environment.

@r32190 it fails to connect with linux. i will give it another shot but it seems like it wont make a connection with the router

If you have more PC, test the file copying between two PC with netcat. Assuring they are working first.

I will try using a different distribution later on today.

@maurer. power issue?  how much power is it missing and to where exactly?
can we hard wire it?

(Last edited by faramisimo on 21 Oct 2011, 19:59)