Bluetooth Proximity Support

As an expermiment I have build a module which uses my Sitecom bluetooth dongle to determine the RSSI value of the bluetooth devices I have defined, so it can determine their location. You can link a bluetooth device to a user to DomotiGa knows which user is around.

You have to make sure that your bluetooth device(s) and server are paired and connected. You can arrange the pairing via the bluetooth manager on your server's gnome panel. To make a connection you first need to figure out which channel your phone is on.

$ sdptool browse 00:11:22:33:44::66

Use your own phone's MAC address. This will list all sorts of bluetooth services that your phone offer. Well the next step is simply to tell your system which channel you want to talk RFCOMM. RFCOMM is a special bluetooth serial port emulation over radio frequency (hence the name rf communication). It is quite literally an implementation of the RS232 serial protocol over radio. Bluetooth can handle several rfcomm channels consecutively. We just have to decide which one we're going to use for this exercise.. This is dead easy. Just look at the output of the sdp search which you ran just now and look at the RFCOMM channel number in the 'Dial up Networking' service section. In the case above, it's channel 1.

All you do now is specify that channel in your rfcomm.conf, so on my system that looks like this:

$ cat vi /etc/bluetooth/rfcomm.conf
rfcomm0 {
  bind yes;
  device 00:11:12:50:0C:EB;
  channel 1;
  comment "PPP connect";
}

When you use the Bluetooth browser from DomotiGa's Tools menu, you should see an RSSI field strength instead of 'Not Connected.'

Install Pre-Requisites

sudo apt-get install bluez-utils

Startup Log Entries:

2008/11/17 21:11:18  My Phone status changed to 0 and Near 
2008/11/17 21:11:18  Bluetooth Proximity detected that 'Ron' is home!

To Do