This was the main problem, how to get the needed power for the computer. I decided to use an inverter to convert the car's 12 VDC into 230VAC needed for the computer. The computer needs about 120W and the inverter I got from Conrad Electronics was able to supply about 160W continuously.
User interface ?
Of course we need a display and a keyboard to control the player (play, pause, stop, next, etc). And of course having a standard PC keyboard and monitor is quite big for a car (excepted if you've got a 18 meters long Limousine :-). So I decided to use the LCD display from MatrixOrbital. This display allows to show 20 chars on 4 lines. This is quite enough to print the needed information. To allow us to see a title song greater than 20 chars the program just scroll it :-). The LCD display just need to be plugged in a serial port set at 9600 bps and you can simply send text to it and it's displayed.you can also send command to switch backlight on or off, clear the LCD, etc.
And to be able to send command to the computer I use a keypad which is directly connected to the LCD display, that is, the LCD allows a keypad with up to 25 keys (5x5 matrix).
Program
To drive this we need a program, I decided to use Perl scripting language to do that because perl just rocks :). So the program is basically a mp3 player frontend (such as amp, mpg123, etc). I started this program and now a friend of mine contribute to it so we can get it even better. You can get the source here or get the absolutely-latest-version on our CVS repository.
LCD and Keypad emulation
To be able to use the kitplayer frontend without having to use the real MatrixOrbital LCD display nor the keypad we've coded a lcd/keypad emulation. The emulator is included in the source code. Actually there is a keypad emulator and two lcd emulators, one is using ncurses and can be used in any xterm or console, the other one is graphical (click here for some snapshots) and uses X11::Xforms CPAN Perl Module to display. It's still quite buggy but it works :-)
Want to see it ?
At this stage I think you want to have some pictures of this Kitplayer :-) Here's some:
Source code
The source code is free (also because it's only few scripts :-) and here is the latest developement version (no stable final version available for now)
CVS Repository
Sorry, the repository is not available.
