Arch Linux

psi.neamf

Member

Registered: 2007-01-16

Posts: 9

3G USB Modem not Working. [SOLVED]

Greets!

Just started playing around with Arch and I really like it
Have been using Gentoo for the last two years or so.

Arch system

# uname -a
Linux testing 2.6.16-ARCH #1 SMP PREEMPT Thu May 11 07:20:39 CEST 2006 i686 AMD Athlon(tm) 64 Processor 3200+ AuthenticAMD GNU/Linux

I am using a 3G USB Sentech modem.
The kernel (both Arch and Gentoo) uses usbserial and ipw drivers/modules
for it and states that those modules are for Axity3G/Sentech South Africa.
This modem works fine on my Gentoo system.

The modules do get loaded in my Arch system.
I have my /etc/ppp/peers/sentech script, my /etc/chatscript/sentech and my
/etc/ppp/chap-secrets set up.

There is a node at /dev/tts/USB0 for the device.
lsusb lists the device with product and vendor id.

My problem :

pppd call sentech

just does not do anything. The script either hangs or fails, and my modem doesn't
respond at all. Does anyone have any idea what could be wrong ?

Much appreciated
psi

EDIT:

Some more info.
The device node on my Gentoo system is created as follows:

crw-rw---- 1 root root 240, 0 Jan 17 00:05 /dev/ttyIPW0

but in Arch it is

crw-rw---- 1 root root 188, 0 Jan 17 00:05 /dev/tts/USB0

I don't know anything about coding drivers, but the ipw.c (driver source) contains:

#define IPW_TTY_MAJOR   240     /* real device node major id, experimental range */

and i was wondering if udev creating the character device with major number 188
could be the cause of the problem, and how to make udev create it with a different
major number?

thx again
psi

Lone_Wolf

Administrator

From: Netherlands, Europe

Registered: 2005-10-04

Posts: 13,074

Re: 3G USB Modem not Working. [SOLVED]

Immediately after inserting the 3g modem , check dmesg .

It should tell you what serial device is linked to the modem.

my 3g pcmcia card gets linked to /dev/ttyS0 & /dev/ttyS1 .

Both minicom and kppp (kde gui frontend for ppp) then access the modem port as /dev/ttyS0 .

---

Disliking systemd intensely, but not satisfied with alternatives so focusing on taming systemd.

clean chroot building not flexible enough ?
Try clean chroot manager by graysky

psi.neamf

Member

Registered: 2007-01-16

Posts: 9

Re: 3G USB Modem not Working. [SOLVED]

I have indeed checked the dmesg results, prior to posting
and it says "device now connected to ttyUSB0" thing is,
there is no such node in /dev, only the /dev/tts/USB0 node.

I created a udev rule to make the other node, that still made no difference.

On further inspection, my Gentoo kernel is 2.6.15. I installed the 2.6.17
kernel and bam, it creates the node with major=188 and minor=0 where
the 2.6.15 kernel creates it with major=240 and minor=0.

So my question becomes:
How do I make the newer kernel, or udev, create a node with the correct
major/minor numbers ? Or could I perhaps just modify the line of
code in the driver (ipw.c) mentioned above? Will try that later tonight.

Thx

filoktetes

Member

From: Skien, Norway

Registered: 2003-12-29

Posts: 287

Re: 3G USB Modem not Working. [SOLVED]

The /dev/tts/USB0 is the correct device to use.
To check if it works, you can use minicom (you have to set up the serial port for it by running minicom -s as root and save the default config).
Or try kppp, but it doesn't let you choose /dev/tts/USB0 as device, but you can make a symolic link (ln -s /dev/tts/USB0 /dev/modem), and use /dev/modem.

psi.neamf

Member

Registered: 2007-01-16

Posts: 9

Re: 3G USB Modem not Working. [SOLVED]

Hi again.

Thx for input so far and also, I apologize for going on about my Gentoo box, but it's the
only way I can test/compare things.

I compiled kernel 2.6.19.2 on Gentoo box and the modem works now (it didn't on 2.6.16/17)
I had done some research and found that the newer kernels had patches added
to that specific driver (ipw.c.)

So I went ahead and tried to install 2.6.19.2 on the Arch box and ended up with
a kernel panic. I have no idea how kernel installation works in Arch, it gave warnings
about ?PATA? (i know it refers to IDE, but don't know the implications) and that hdX
might change to sdX ?!.

I think the new kernel will help with getting my modem working, so I will go ahead
and study the wiki on mkinitcpio (haven't used it before) and get my kernel panic sorted.

Thx again. I will post if I run into something I can't solve
psi

psi.neamf

Member

Registered: 2007-01-16

Posts: 9

Re: 3G USB Modem not Working. [SOLVED]

Finally! Super happy

Gonna Arch the weekend away  :twisted:

Kernel panic sorted and modem works with 2.6.19.2.

Need sleep now, hehe.

L8r