May 14, 2003

Ricochet USB Modem on a Laptop

Author: Benjamin D. Thomas

nitman writes "I am using this Ricochet service. Presently it is available in Denver and San Diego only. Anyhow, their modem works perfectly well with Linux. It supports both USB and Serial. However, to get the best results, use USB. And their friendly staff (some of them) is willing to help users via e-mail. The official corporate stand is to support Lindows only!

My redhat 7.x (2.4 kernel) system was able to easily find the modem. Kudzu found the modem and configured it. So far so good! If you are still using 2.2.x kernel, make sure you apply the USB support patch. However, there are few things that still need to be done.
On a console type:
insmod usbserial vendor=0x0870 product=0x0001
Also, make sure that the system has USB device nodes. If not, then you will have to create them:
mknod/dev/ttyUSB0 c 188 0
mknod/dev/ttyUSB1 c 188 1
and so on.. I went up to four nodes.
To make things a little easier for minicom to work, add a soft link:
ln -s/dev/ttyUSB0/dev/modem
(Make sure you delete/dev/modem before re-linking)
With minicom you test the AT commands. ATI4 will display manufacturer id. I use wvdial to dial out, and the conf file looks like this:
[Modem0]
Modem =/dev/ttyUSB0
Baud = 460800
Init1 = ATZ
SetVolume = 0
Dial Command = ATDT

[Dialer Ricochet]
Username =
Password =
Phone = 3333
Inherits = Dialer Defaults
Stupid mode = 0

I have seen many different variations to above settings. Some people have been able to get the modem to work with these nodes:/dev/tty/ttyUSB0
or even/dev/tty/ttyACM0
It all depends on your distro. I am using Redhat 7.1 with 2.4 kernel. However, there seems to some problem with Redhat 8.0. On my laptop (Thinkpad 600E), Redhat will just not dial out. With Redhat 7.x it works perfectly. But there is a minor catch.
The Catch
During boot up make sure the modem is off. Do not let kudzu detect it. If you do, you will have to reboot let it de-configure it. Once you are in favorite desktop (GNOME), turn on the modem, let it initialize itself. You will see the lights go green. Dial out..
Another thing to note is that I tried putting:
options usbserial vendor=0x0870 product=0x0001
in/etc/modules.conf, so I don't have to type:
insmod usbserial vendor=0x0870 product=0x0001
again and again. But it does not work that way either. I have to issue that command before I dial out (or Dialer program won't detect modem and crash). Another bug I found is that if rp3 (my dialer in RH7.1) crashes during dialing out, there is no way to fix it but to reboot and re-intialize the USB-UHCI and USB filesystems.
To find out more about the general settings (not for Laptops) please check these sites:
http://www.tcu-inc.com/Articles/15/USB.html
http://clue.denver.co.us/pipermail/clue-tech/2002- October/006032.html"

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