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Re: Re: How to get Bell Canada 3G USB network up?



>> option                 12918  2
>> usb_wwan                6147  1 option
>> usbserial              21120  7 option,usb_wwan
>>
>
> I am worried about this 'usb_wwan', it seems to do exactly what 'option' is
> supposed to do. rmmod usb_wwan ? Is it nm doing this ?

As you can see from the lsmod output, usb_wwan is required by option.

>>> I suggest that you go back to the beginning, probably a clean, fresh
>>> install of
>>> Squeeze, stick the modem in and see what happens. Or a live cd, or, ..

So I've done that now (fresh squeeze install on my netbook). It's just
like in the Ubuntu live system: the modem is being recognized and
usb-modeswitched out of the box (some of the times), configuring the
country/provider makes it work, but same story: (1) half the times I
plug in the modem, it won't work at all (modeswitching works and it
shows up in the nm menu, but choosing 'activate' just spins for a
couple seconds but does nothing); (2) if (1) worked, then just as with
my hand hacked older Debian setup, after 20 seconds it will loose
connection about in half of the cases.

BTW lately I've cared to observe the exact moment when it 'crashes'.
It is 20 seconds after connection initiation and really exactly when
it switches from "U" (umts) to "H" (HSPA).

> The modeswitching is just the first stage, a very annoying hurdle, it has
> nothing to do with connecting.

Yes I know, but as I've described, there must be *something* in the
way that Debian's/Ubuntus builtin usbmodeswitch works that leaves the
modem nonworkable in half the cases. Whereas with my own modeswitching
script that's never an issue.

> ( but indeed, if it does not work it "won't
> allow you to connect" although that sounds confused to me. )

(To help explain what I wrote above:

* the modem LED is off after plugging it into the USB port and before
usb modeswitching happens
* after the mode switch runs, the modem LED is blinking in blue
(sometimes it inserts a lone blink in green between the blue ones, no
idea what it means)
* when the modem is connected, the modem LED is lighting up in constant blue
* when there has been traffic, the modem LED color changes to green,
orange, yellow or purple (I don't know what these colors mean, it
might indicate the network speed), but it stays lit up constantly
* when the modem is disconnected (either on purpose through the nm
menu, or when I move to a place with no network coverage (metro), or
when it ' 'crashes' at the 20 second point), it goes back to blue
blinking

Thus I can see when the usb mode switch happened because I see the
blue blinking. Which the fresh Debian install / Ubuntu live system do
100% of the time; only, in what seems to be exactly half of the cases,
choosing connect from the nm menu (which I have to do, I haven't
configured nm to connect automatically) will not bring the connection
up. Which I can see both because nm just goes back to disconnected
state after a couple seconds, and the modem never goes from blinking
to constantly lit mode.)

>
> The second stage is the loading of the proper module which makes the device
> accessible. ( presence of /dev/ttyUSB* )
>
> Now we can 'talk' to this thing. It works like an old fashioned
> telephoneline-modem with 'AT-' commands, we can tell it to 'dial',
> disconnect, scan for available networks, measure signalstrength etc.
> One might use 'minicom' to play with it.

Yeah I know, I used those a bit in the old 56k telephone modem times.
But I haven't really tried to find a command list for 3G modems.

(Also, I'm not sure what to do: how would I bring ppp up in such a
manual scenario, i.e. from minicom? Also, in the old times, once ppp
is up, the computer normally wouldn't send AT commands to the modem,
except to interrupt ppp stream to bring it down. Since nowadays modems
need to transmit state changes like the change from UMTS to HSPA, I
wonder how that happens. In any case, I've got no idea what to look
out for, and also, even if I knew to pinpoint it down to a particular
feature, I'd have to observe what nm is doing, too, to know what else
to try.)

>
> Or use 'chat', which is part of the package 'ppp', to write scripts that
> manipulate the modem.
>
>>
>> How do you connect, using nm or something else?
>
> I avoid nm like the plague, but that said, if it is ready it might be
> beautiful. I prefer low-level tools.

Yeah I tried to go with the low-level tools too, at first, then after
being unsuccessful gave in and went with nm. (I might try to find the
mails I sent during that time; after unsuccessfully trying ppp, I also
tried to go that "option" (iirc) route (the one that supercedes ppp),
w/o success either.)

> Like wvdial. Run 'wvdialconf' -if- the modem is accessible. And then tweak
> /etc/wvdial.conf .

I didn't try wvdial. Hm, I'll have to surf around to figure out how to tweak it.

Christian.


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