CarPC Basics

This is a basic introduction on how to create a carPC. I wish I still had pictures from my car installs but I don't, so you'll have to use your imagination or this for inspiration.

Power:​

Essentially you have 2 choices for power for your carPC; DC or AC. DC being that you run a DC-DC powersupply like an Opus [1, 2] which connects straight to the car battery. The second one is a DC-AC inverter. The DC-AC inverter converted the DC power from your DC car battery into a AC powersource, exactly like the one you use for your home desktop PC, so essentially you are able to use a normal PSU.

Both can be quite expensive, but if you are more hands on than others, you might want to try making a DC-DC PSU yourself. There are heaps of schematics out there, especially on MP3Car Forums.

I've tended to use DC-AC inverters's personally because; 1, my systems have all be relatily high power drawers {Except for a EPIA setup I made} and 2, IMO, they are easier, just connect them straight up to the battery, through your firewall, as you would with your AMP cable for your sound system. Then it's just a matter of hooking up a small {read small, but not so small, the amps burn it out } on/off power switch into the dash somewhere. This eliminates the crank shutdown problem, although some DC-DC PSU's have overcome the crank issue. But there really isn't any feasble, high wattage, cheap DC-DC PSU's out there. There is one alternative which I am considering using for my next setup. This one. I'll try and get some links to some schematics for that DC-DC PSU if anyone wants to try their hands on that too.

Visual:​

Again we have 2 options, no visual aid, or visual aid. What I mean is that by no visual aid is it's just the music going straight from the PC to the headunit or amp, maybe a remote control for song and volume control.

When you start getting into looking at something {LCD, Dotmatrix LCD, that kind of thing} it starts getting a little more awkward. There are so many choices. You can just have a Matrix Orbital {or similar} LCD display, composite LCD screen, touchscreens and/or VGA screens. In most of my installs I used either a VGA or composite LCD screen. I'll briefly go over how each one can be used.

Matrix Orbital typed LCD:
Obviously you'd have to have the whole setup finished and running customised to use one of these as you don't have a visual aid as such like using a LCD. These are most cominly combined with a simple remote to play, pause, stop, adjust volume and skip tracks. They would be setup to just scroll text, and if big enough, show some system statistics.

Composite LCD:
These are great if you only intend on watching movies and playing music as they are dirt cheap {just check eBay}. The downside being that since they use composite their resolution isn't very good. Normally you won't be able to get it to run any more than ~640*480 {depending on LCD dimensions}. But there is a way that you are able to get a "little" more eye candy {if you want to call it that} from it. See here.

Touchscreens:
These are the most expensive out of the lot, but are worth there money. IMO, for most screens in a carPC setup {~7"} they aren't really needed and getting the cursor to select the right option on something can be clumbsy thing. There is an alternative however if you can't afford a touchscreen but so desperately want one. It's a film that goes over the top of a monitor/LCD screen that uses X and Y co-ordinates to plot the cursor. These can be used on both composite and VGA screens. See here.

I won't bother about VGA, as I'm sure most of you all well know that it's the best option in most cases. VGA will give the best resolution.

I'll be updating this every chance I get, please feel free to correct me or give me advice on what to add in. If you have any questions, please post them in here, so I and other people can answer them here to help others later on.

Hardware:​

There are soooo many things to cover in this part, so I'm going to do it bit by bit.

Storage:
Where to store all your music and video's {that's if you choose} ? Some people find that a 40gig did fine, but since my music collection is 35gig and counting, and then I still had to fit on music video's and movies, my 40gig just wasn't cutting it. So I opted for a 120gig. That was sufficient enough.

People tend to think that all the bouncing and everything will cause damage to your HDD {in the case of a normal 3.5" HDD}. If your a speed freak maniac, then this is probably true, but for normal everyday driving there is no need to worry. The main thing you need to worry about is heat. My Barracuda 120gig 7200.7 would easily get to burning temps and cause the system to shutdown. A simple 60mm fan blowing onto it fixed that problem.

But, idealy, laptop HDD's are perfect, they are built to be bashed around a bit, if you can afford one then go for it.

But if your still paranoid about your hard drive platter getting scratched by the head from vibration, then some simple washers or some foam to seat it on will be ample support. {Thanks Roman for that tip}

If you really want to show it up, you could try a RAID setup I wish I could remember the link where I saw someone setup 4x40gig laptop HDD"s in a RAID1 setup for their carPC.

Video:
The most economical would be to have onboard video as we aren't playing Doom3 or HL2 on our carPC so we don't need a massively big video card, but sometimes, onboard video cards just can't cut the butter when it comes to DVD and MPEG decoding. Besides the EPIA range of motherboards, you won't really find anything {pre KM400/P3 onboard mb's} that will do the job. So you'll need to invest in a low profile video card, or if you've got the space something a little beefier.

For the budgetist, a cheap MX200, MX440 low profile will do, while for the extremest that want the best, I wouldn't go past the 8500, 9600, 9700 9800 AIW's. They will perform magically.

Sound:
If your using a decent HU, then you wont need a PCI soundcard as the onboard will do fine, but if you intend of doing away with the HU and having the "line-out" going straight to the amp, then a decent sound card is a must for audibility. The Soundblaster 5.1 Live DE's are what I would consider a starter for that kind of setup.

Just configure the software to run the sound as a 2.0 sound channel setup and run it from a 3.5mm phonejack into a left and right channel rca plug cable.

Network:
As the price of wireless is getting cheaper every day, I'd suggest using this as you won't have to run a cat5/e cable into you garage everytime you wanted to upload something.

Or if you can't afford that, just make a RJ45 connector in the side of the case for remote access if the case is hidden.

Topics to cover
Software
Input devices

Ryan

 

Reserved

Ryan

 

please go on, im impressed .

pics of your setup would be great to see also!

 

Software ware would be good to know too! A bluetooth remote would be a good idea to use imo and a small display from winamp....

To help the harddrive live better.. You could use tight foam to hold the drive in a custom case/holder. This will prevent a lot of damage which could happen.

 

i still dont get this whole crank/powerdown issue. it didnt make sense over at mp3car either.

it just seems that the pc would be getting turned on and off all day...not the greatest rig if you were a courier or something.

 

make it like a turbo timer..for say 5 mins?

 

Sorry I haven't updated this in a while, my internet has been chugging along on the OCAU forums with being capped and all, so I haven't been on. The only chance I get is when I'm at my girl's house.

The idea behind the DC-DC PSU's that bypass the crank I think is that they have a large charge capacitor.

The only time that the crank issue comes into effect is when PSU/Inverter is hooked up the lighter or something else that only runs when the accessories or on is on.

Thanks for the heads up with the help with the HDD vibration too.

Ryan

 

very interested, good writeup so far mate

information about software would be greatly appreciated

 

Thanks for the guide to Car PC's. I'm currently developing a Car PC system for mp3's/video. So helpful threads like this really go a long way to assist with my project.

 

There is another option in the way of power, which seems to be much more feesable than an opus and use less power than an inverter:
This:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=3670&item=6725316893
Mixed with:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=3670&item=6720405529

The "ITPS" overcomes the startup-shutdown issue by turning the computer on 10 seconds AFAIK after the car has started and then 5-10 seconds after your car is turned off the "ITPS" sends a soft-off message to the PC and it shuts down. This is all automatically done and a helluva lot cheaper than an opus.

The number 1 software for a car PC is Frodoplayer, its a good app designed for touch screen LCD's download it HERE its also cross-compatible with other software.

Also for hardware a USB GPS device is also a must they are cheap as (sub $100) The software can be downloaded from the net.

It just means that if your carputer is hooked up to the battery- when you crank the charge comming out of your battery lowers down to ~8V-not enough for the carpc to run so therefore it turns off, this is avoided with the items above.

 

Hrmm, thanks. I'll update the original post tonight some time.

I get my new {well old} car hopefully in the coming weeks, and I've got plans for a custom fibreglass subbox/PC housing

Ryan

 

Well that is subjective, I use Mediaengine for my carPC, also if you have a bluetooth dongle and bluetooth phone you can use Phonecontrol software that intergrates into Mediaengine to act as a hands free kit

 

Another hardware route.

If all you're out to do is play Mp3's , GPS navigate, play movies etc, you don't need a whole hell of a lot of processing power to do that.

A cheap laptop - second hand , usually with a broken screen can put you in the 600-900mhz range with a laptop HDD for around $200-300.

Add a touch screen and you're away

Power is mostly a non-issue since a lot of laptops have a DC-DC converter board in them that means they will quite happily run off 12v.

Well lets say I've tried about 4 different laptops with voltages ranging from 12-20v, and as long as you don't run over their rated voltage they normally work fine.

Admittedly the 20v laptop, won't charge of 12v, but it will run all day on that with battery removed.

 

Composite LCD?
I found this for sale over at Cool PC

http://www.coolpc.com.au/catalog/index.php?cPath=126_51

So do you need to solder a composite LCD connector to a standard VGA (like they did in the MP3car forum) before you can make it work?

 

uhh if its for a carpc you wont be able to see much on it.

 

It'd be enough to display maybe scrolling text. But in that case, a matrix LCD would work better.

Ryan

 

5inch is really the smallest you would want to go, psOne lcd screens are good cheap lcd's for this. No need to do the vga mod just run it off the tv out, does well when combined with one of the carPC players just don't expect to do much 'windows' computing on a screen like that.

 

Alright, I've finished off the hardware bits. I'll add in some of the information that you guys have posted up here too.

Ryan

 

After doing some research, i've found that an X-box works perfectly for a car pc setup, it has all the video decoding options and more than enough grunt to play mp3's etc, plus you can get car chargers etc to run it, so it seems like it would be a good way to go.

 

the adapter is nothing more than a regular run of the mill power inverter, you're better off getting a decent 300 or 400W one. Not sure how much juice an xbox sucks up, anyone?