7.8 Cool Bluetooth Tricks

Aside from the everyday file management and connectivity, Bluetooth on Linux provides scope for some fun applications. This section outlines a few of them, mostly involving interfacing a cell phone with your computer.

7.8.1 Use a Bluetooth Cell Phone to Control Presentations

Wireless devices that control presentations have been available for some time, but at a relatively hefty price tag, they're probably not worth the investment for the occasional presenter. Instead, why not program your cell phone to do the work?

This trick works with Ericsson phones, such as the T610, T68i, and R520m. These phones provide an advanced ability to map keypad presses to output over an RFCOMM serial connection. In turn , a program running on the Linux side can translate these codes into system input events.

You can find the code at http://www.hackdiary.com/projects/bluetoothremote.

7.8.2 Controlling Music Players

Using a similar trick as mentioned previously, the popular MP3-playing application XMMS can be controlled from a suitable Ericsson phone. The bluexmms program even supports display of the MP3 playlist on the phone's screen. You can find instructions and a download at http://linuxbrit.co.uk/bluexmms.

7.8.3 Proximity-Sensitive Screen Blanking

The BlueZ Bluetooth stack reports the signal strength of an active Bluetooth connection. The KDE Bluetooth Framework has a program that takes advantage of this and activates your screensaver when you take your cell phone out of range.

If you don't run the KDE desktop, then try Jon Allen's Perl script to do a similar task, available from http://perl.jonallen. info /bin/view/Main/BluetoothProximityDetection.