3G Modems

Hello

As part of a project I am working on, it is required to use a 3G modem connected to a Beaglebone Black as the BBB will be placed in a remote location.
I have acquired Sakis3G, and attempted to use some 3G modems, but they did not work, and the script only told me that it was unable to connect to the modem (eventhough it did pick it up).

Does anyone know where I can find a list of 3G modems compatible with the BBB, or reference me to a tutorial on how to connect to a 3G modem manually.
One requirement I have is the modem must have a slot where a external antenna can be connected.

Thank you in advance!
Cornel

I’ve used a Huawei E3131 USB dongle which has an external antenna socket - not hard to setup under Linux, as it presents itself as an ethernet interface. There’s nothing BeagleBone specific about setup, the steps documented here are for debian: http://captainunlikely.com/blog/2013/08/16/fallback-routing-with-linux/ and you can probably find more detailed ones with google.

google modeswitch

google modeswitch

I've used a Huawei E3131 USB dongle which has an external antenna socket
- not hard to setup under Linux, as it presents itself as an ethernet
interface. There's nothing BeagleBone specific about setup, the steps
documented here are for debian:
http://captainunlikely.com/blog/2013/08/16/fallback-routing-with-linux/and you can probably find more detailed ones with google.

Some of my blog entry for enabling 3G modem with Cubieboard and Via APC may
help you.

http://sijisunny.com/2013/06/27/3g-modem_cubie-board/

http://sijisunny.com/2013/02/09/configure-modem/

Hey Mike!

Thanks for the post! I am using Angstrom so will have to look for something telling me how to do it on there, but I think I will go buy a Huawei E3131!

Regards
Cornel

Install usb_modeswitch and after that:

http://wiki.mentorel.com/doku.php/udev-disable-zerocd

Hi,

I assume you are looking at a 3G modem that interfaces and is powered by USB interface. There are a number of issues you have to resolve:

3G modems can draw can draw quite a bit of current. The current consumption is variable and depends upon modem activity and 3G signal level. It can exceed the BBB USB port current limit on the BBB. So you may need a USB hub to power the modem. As an example the Sierra wireless modem I used on the last project could draw up to 600 MA when attempting to register on the 3G network.

Angstrom by default uses connman for network management and ofono for modem management. Documentation for these tools is rather sparse and terse. Depending upon the modem you intend to use and your networking requirements, it is likely that you will have difficultly using connman/ofono. I have found it easier to disable connman:

systemctl daemon-reload
systemctl stop connman.service
systemctl disable connman.service

And then start networking using:

/etc/init.d/networking start

To manage the modem connection you can then use pppd in the traditional manner. It does work well. The exact method of setting up PPP depends upon your modem and carrier. The PPP manual pages are more than adequate.

Alternatively you could install NetworkManager/modem-manager, which might make the setup like a debian/ubuntu desktop.

Once you have this working you then need to consider the modem reliability. Some modems occasionally do soft resets and drop the USB connection. This is a problem for unattended remote operation. For my last project I discovered that the modem would intermittently drop the USB interface when the 3G signal level was low. This caused problems with PPP and we found it necessary to write a helper application to shutdown PPP when the USB connection to the modem dropped out and wait until the USB serial ports to the modem were re-established before starting PPP again. Hopefully you won’t have such problems, but you need to do tests with low fluctuating 3G signal levels.

Hopefully you won’t experience all the problems we had.

Regards …