tb63
Posts: 14
Joined: Mon Aug 06, 2012 2:40 pm

huawei e1692 - e156

Wed Sep 05, 2012 9:37 am

I have problems with huawei 3G Modems ( same problem with different models )

Power is ok. as I tried several solution ranging from powered Hub, Y cables, custom Y cables .... as indicated in some posts.

Modem-swithch is ok as I disabled other funtionality with AT+U2DIAG=0

When I try to open the port ... it take 9-15 seconds to open ( on windows with the same program it take 0.0003 seconds )

>>> import serial
>>> s = serial.Serial('/dev/ttyUSB0')
Hang for 14 seconds

After open if I try to send a char ... hands for long long time and nothing back from the dongle :-(

Somebody have some experience like this

Regards

obcd
Posts: 917
Joined: Sun Jul 29, 2012 9:06 pm

Re: huawei e1692 - e156

Wed Sep 05, 2012 11:23 am

What driver is it using to communicate with the modem? I assume the modem emulates an ftdi or prolific usb2serial device. What info do you get on lsusb and on lsmod?
Some of the older ftdi chipset are causing problems with the Pi usb implementation. Maybe your modem is suffering from this as well.
What version of the os are you using? Did you enable the latest kernel patches to improve usb?
uname -a should give you the kernel revision.

tb63
Posts: 14
Joined: Mon Aug 06, 2012 2:40 pm

Re: huawei e1692 - e156

Wed Sep 05, 2012 7:19 pm

Thanks obcd for yur support

uname -a
Linux raspberrypi 3.1.9+ #272 PREEMPT Tue Aug 7 22:51:44 BST 2012 armv6l GNU/Linux

lsusb
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 002: ID 0424:9512 Standard Microsystems Corp.
Bus 001 Device 003: ID 0424:ec00 Standard Microsystems Corp.
Bus 001 Device 004: ID 12d1:1001 Huawei Technologies Co., Ltd. E169/E620/E800 HSDPA Modem
Bus 001 Device 005: ID 0409:0059 NEC Corp. HighSpeed Hub
Bus 001 Device 018: ID 046e:557f Behavior Tech. Computer Corp.
Bus 001 Device 007: ID 0718:0619 Imation Corp.

lsmod
Module Size Used by
snd_bcm2835 21505 0
snd_pcm 80650 1 snd_bcm2835
snd_seq 59372 0
snd_timer 21638 2 snd_seq,snd_pcm
snd_seq_device 6916 1 snd_seq
snd 57253 5 snd_seq_device,snd_timer,snd_seq,snd_pcm,snd_bcm2835
snd_page_alloc 5347 1 snd_pcm
option 15915 0
usb_wwan 12850 1 option
evdev 9470 2
joydev 9698 0
usbserial 37414 2 usb_wwan,option

What should I try to solve ?
Regards

obcd
Posts: 917
Joined: Sun Jul 29, 2012 9:06 pm

Re: huawei e1692 - e156

Wed Sep 05, 2012 10:02 pm

You could start by updating your kernel. Do a search for hexxeh updater and run sudo rpi-update. They are now at 3.2.27+ #102 (not sure about the build number.) Also make sure you have the latest usb patches enabled in the /boot/cmdline.txt sdhci-bcm2708.enable_llm=1 is likely one that isn't set as default.
If you have the Pi connected to internet, try to control it with an ssh session from another pc.
Doing so, you can remove the keyboard and mouse from the usb ports, as some people are having issues with a mixed setup of low speed and high speed usb devices.
Connect the modem to a powered hub to ensure it gets enough power.
The pi usb ports can only deliver 100mA, and for some devices this simply isn't enough.
I can't guarantee it will fix your problems. You could check out the usb elephant thread and the one about the 8000 interrupts/sec (start at the end and move backwards) The usb host ports are a weak point of the Pi soc.
usbserial seems to be the driver that is responsable for creating the ttyusb0 port. It also loads if I plug in an ftdi dongle. The other one seems to be specific for the modem.

pygmy_giant
Posts: 1562
Joined: Sun Mar 04, 2012 12:49 am

Re: huawei e1692 - e156

Wed Sep 05, 2012 11:26 pm

Hi - I am actually posting from my Pi via a Huawei E220 - search the forum for 'Sakis' and see what turns up...
Ostendo ignarus addo scientia.

tb63
Posts: 14
Joined: Mon Aug 06, 2012 2:40 pm

Re: huawei e1692 - e156

Thu Sep 06, 2012 6:04 am

pygmy_giant » am actually posting from my Pi via a Huawei E220 - search
Thanks. I know Sakis ( actually I was planing to use pyhumod ) buy none on them work as they can not open the serial port. Could you describe your system .. kernel, USB HuB .. power ...
Thanks
obcd »You could start by updating your kernel ...
Yesterday I tried rpi-update Every think went fine but now my SD does not boot and PI is flashing green :-(

tb63
Posts: 14
Joined: Mon Aug 06, 2012 2:40 pm

Re: huawei e1692 - e156

Thu Sep 06, 2012 7:06 pm

Solved.

Updating the kernel solved the problem :D no need to modfy the /boot/cmdline.txt

Linux raspberrypi 3.2.27+ #114 PREEMPT Tue Sep 4 00:15:33 BST 2012 armv6l GNU/Linux

Thanks obcd

ppuskari
Posts: 38
Joined: Sat Jul 07, 2012 4:04 am

Re: huawei e1692 - e156

Sat Sep 08, 2012 3:39 am

Interesting.. Your SD was "fixed" with the latest firmware... Mine was broken in an unusual but related way to your fix...

When I updated to the most recent kernel/firmware on September 6, I suddenly was left with a system that ONLY found the SD rca output active after a quick screen flash about 1/10 the time as normally happens.. the LCD panel on the dvi went out, but the pi was still alive.. SSH into the pi, and changed the config.txt file to force hotplug, and then reboot.. Now the video is back to normal. I went back and put the previous firmware back on and removed the force hotplug entry and everything was good as well like normal. re rpi-update and boom no dvi output again... Oh and this was regardless of overclocking or not. I tried all the permutations :)

Maybe it is related somehow.

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