syquestrd270

I'd like to build an in-car computer to play Mp3s and was hoping someone else here has done such a project. I'm interested in the fanless nano-ITX boards from VIA as a platform, but I don't know exactly what I'm going to do about power or a display.

I have an external USB2 laptop hard drive enclosure about the size of a Palm Pilot that I would want to use for storage, and I don't really want to purchase a case. I have the audio inputs available on my Alpine head unit, but I don't know what to do for power to run the computer. I could get an inverter and a regular ATX power supply, but that would take up more room.

Has anyone tried running a computer directly from a car's 12v system?

I also need some sort of display. I don't really want to shell out a lot of money to get a LCD screen for the dash, but one of those small scrolling screens might be nice for displaying tracks. I'd also need some way of navigating directories and playing songs. I'd rather go with a Linux solution if possible.

I have a Honda Del Sol with cargo bins behind the seats, but I'd have a more difficult time routing power to the computer if I put it behind the seats.

Any ideas?

ggadgit

Hi there:

I looked into this at one time, and the best place that I found to ask questions and do research was http://www.mp3car.com/
esp. their forums. Good luck on the project, let me know how it turns out.

ps http://www.idotpc.com/ has a dc to dc power supply and a Car Power Sequencer & Dropout Regulator .

Scorpion23

I did this myself a few months ago. When I did it they didn't have the nano-itx boards out, just the micro-itx. But it's still only 17x17cm.

I use mine for mp3s, dvd playback, gps navigation and OBD II diagnostics. Like you I didn't want to use a case, so I ended up placing the mobo in the center console between the two front seats. I got a 7" touchscreen LCD that I mounted above the rearview mirror, where I can glance at it without moving my head. I'm not sure how much you want to spend but you can get a 7" w/ touchscreen for under $250.

As ggadgit was saying, a dropout regulator is the way to go. Get one of the atx power supplies that VIA makes for their mobo's. They work off of 12v DC and can be put inline with the dropout regulator. In addition they're so small that they clip onto the motherboard itself with no wires. The regulator that I use actually starts and shuts down your computer for you whenever you turn your car on or off.

As far as your HD, I'm not sure that you'll be able to boot from a USB hard drive. I ended up putting a regular 3.5" under the front passenger seat with an anti-shock mounting system. Since you already have a laptop HD you can just get an anti-shock mount for a 2.5" drive and use it with an IDE cable converter.

I'm running a stripped down version of WinXP instead of Linux since all the functionality that I wanted wasn't available in Linux. Namely the OBD II interface program. For the Winamp interface I used the Comtrol program that lets you have over 15 buttons interfaced through the serial port.

I'm not at home right now, but when I get back I can post pics of how I did everything and links for where I got it.

__________________
"Empirically observed covariation is a necessary but not sufficient condition for causality" - Edward Tufte

Redjake

one of my friend's girlfriend's dad's did this. he said it worked pretty well.

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Off the record, on the q.t., and very hush-hush.

syquestrd270

Thank you all for the good information. I'm going to start pricing out components and I'll let you know what I figure out.

If I get it all together anytime soon I'll post images.

Mondak

Hey man - there is a guy working on this at another board I go to and he is keepting a project log. Seems to be doing a great job too. You may not need to go through all this with the custom interface and control panel, but...

http://forums.bit-tech.net/showthread.php?t=48184

Let me know if it helps.

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All truth passes through three stages:
First it is ridiculed
Second, it is violently opposed and
Third, it is accepted as self-evident.

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Redjake

I go to Bit-Tech as well. Best computer forums in the world

__________________
Off the record, on the q.t., and very hush-hush.

telekinetic

I did this a year ago.... mp3.telekineticfool.com has my setup. Definitely go check out mp3car.com, it has by far the best resources.

Feel free to pm me any questions you've got, I can probably answer them or point you to the answers.

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twisted no more

Scorpion23

Ok. Sorry about the delay, but here?s what I did.

If you look in the first picture you can see the center console of my car. The three black buttons on the front let me control winamp with my fingertips while driving. They?re set to play/next track, pause/stop, and next playlist. The interface program is comtrol, which can be found here: http://diba.hotbox.ru/comctrl/ It lets you have up to 15 buttons run off the serial port. I use 3 for winamp and the rest for other system functions.

<img src="http://s95238930.onlinehome.us/cconsole.jpg" alt=Closed Center Console'>

Next you see the console when opened. I know it?s a mess but it gets the job done just fine, and you can?t tell anything is in there when it?s closed. The blue arrow is pointing to the power supply. That should give you an idea of how small it is. The 60mm fan right above it is the CPU, and is the only fan on the system. The switch on the top right is for powering the unit off of an AC adapter when I?m loading software or working on the system and don?t want the car idling for 2 hours .

<img src="http://s95238930.onlinehome.us/console.jpg" alt=Open Center Console'>

The next picture is my dash and head unit. The only noticeable modifications are the two power buttons on the bottom and the set of programmable buttons on the top for the navigation system. The rocker switch on the bottom left controls Acc. power to the voltage dropout regulator (more on that later), while the red button on the right is a manual power button for restarts and such.

<img src="http://s95238930.onlinehome.us/dash.jpg" alt=Dash'>

The last picture is of the screen. 7? LCD with touchscreen. All the cables are routed down through the inside of the left A pillar, leaving no visible wiring. This is a screenshot of the GPS nav. system and mapping software.

<img src="http://s95238930.onlinehome.us/screen.jpg" alt=Screen'>

The best part about this system is that you can?t tell it?s not factory from outside of the car. All the buttons are inconspicuous and you can?t see the screen unless you get on your knees and look up at the roof.

For the Dropout regulator you can read about it here:
http://www.mp3car.com/products/itps.html
Needless to say, you have to get one no matter what :-)

Since you?re only thinking about playing mp3?s you could just go with a 2-line lcd display, and a USB interface. The good ones start around $50 and come with sample code, although I?m sure you can find some winamp plug-ins out there already. A quick search turned up this website, but there are plenty more out there.
http://www.performance-pcs.com/catal...a3e9e4791e4f27

For the audio I spliced into the connection between my in-dash 4-disc changer and the line-out port on my sound card. A 3-pole double-throw switch lets me go back and forth between the two.

If you have any questions just ask, although a lot of it you won?t run into until you actually start building it.

__________________
"Empirically observed covariation is a necessary but not sufficient condition for causality" - Edward Tufte

WarWagon

My roomate just did this. Used a keypad up front, computer in the trunk, and ordered a small color LCD screen from Toys R Us that I believe was originally intended for some sort of handheld gaming device DIRT cheap. I forget what he used for software, but it looks amazing, and he's got a TON of MP3's in there now. He has pics somewhere, if you send me a PM I can get pictures for you.