DUN Modem Plugin

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DUN Modem Plugin

Post by admin » Fri May 18, 2012 3:40 pm

This plugin supports car phones with built in Bluetooth modem support, like the Volkswagen "Premium" phone. It automatically creates an internet connection when the phone connects via rSAP, so you are online again and may use services like Google Navigation. This plugin needs root access! It does not work with the trial version.


I will not publish the plugin in Google Play Store because it is not trivial to install. For most (all?) ROMs you will need a special kernel module file (see below).

The plugin does not have a default user interface. After installation it shows up in the installed apps list and in the settings menu of the rSAP app.
DUN Modem Plugin
(56.92 KiB) Downloaded 1245 times
After installation start the rSAP app and open the settings menu. You should see a new entry "DUN Plugin". Touch that entry, scroll down and touch "Install Files". This only needs to be done once.

With VW Premium phones the modem connection should be activated automatically at the next connect to the car, after you had the correct kernel module installed.

Kernel Module

The modem connection needs a Linux kernel module (ppp_async.ko) that is usually not contained in common Android Linux kernels. If you don't have a working kernel module you will get an error "Couldn't set tty to PPP discipline" in "PPP State".

Since kernel modules change with every build it is nearly impossible to create a matching module for every kernel. So you have two options:
  • build the kernel module from scratch using matching kernel sources
  • patch a similar kernel module and test if it works
I'll try to create modules for the most common ROMs, like the Nexus ROMs and major CyanogenMod releases. The kernel module must be copied to /system/lib/modules. This is best done with Root Explorer or with a root shell.

See http://www.android-rsap.com/index.php?o ... icle&id=88 for more information.

Known Issues
  • If modem connection aborts it will not try to reconnect
  • Network connection is different to standard mobile data connection. E-mails are not synced in background, WLAN tehthering is not possible, speed tests do not work and possibly more.
  • If you are connected to WLAN while connecting to the car there is no more internet connection when you leave the WLAN area although the modem connection is still active.
If you have problems or comments please create a new topic if there is no matching topic existing.


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