Laptop remote on/off issue -- SOLVED: s2000 carputer
Whew -- there were a few technical hurdles to get over to get this carputer up and running, but it was worth it. This is in an S2000 - with a Xenarc 7" touchscreen monitor mounted in-dash.
For starters, I wanted to have a laptop-based system, which gives you a few key advantages. For starters, it's flexible. I can drive all day on a trip, and when I get to a strange city and find a hotel, all I have to do is jettison the computer "core", and I've got my laptop for the trip. I can use the map software to scout out the next day's trip, and I don't have to worry about copying anything to the car, I just have to pop the laptop back in! Best of all, zero custom work. (OK, lots of custom work, but not on the laptop itself.). Easy to upgrade!
But -- as you know, there are some drawbacks to a laptop. OK -- just one: No laptop that I've seen has a 'wake on power' function. Worse, you can't hack apart a laptop to remote the power switch up near the driver. No power switch means any system hang means a trip to the trunk to reset it. Bad idea.
I tried fasioning a Wake on LAN cable, tried unsoldering the docking station switch -- that didn't work, as the signal attenuation on the far side of Cat-5 cable was so bad, the switch just wouldn't work. I thought of using a relay, a servo, but then my pal Brent (who gets credit - so I call it the BrentDonkeyMaster1000) thought of a brilliant idea: How about a bike hand-brake? Cheap ($14 in parts), easy (I had a prototype working that night), and totally retro-cool lo-tech. Plus I get a *****in' brake handle to mount by the driver's seat.
The design is pretty simple -- attach the bike brake to the docking station. Squeeze the handle and the brake closes, pressing the power button. Hold down the power button for 4 seconds, and if you have any kind of modern laptop, it forces a reset, which is great for that odd system hang.
Next, I had to locate the handle up near the driver. It's not permanently mounted yet (none of it is permenantly in place yet -- mounting comes later). I ran the cable through the vents behind the seats and into the trunk. (Again, this is not permanent, so the tangle of cables you see there won't be in the final version).
I had to take the spare-tire tools out of the bottom of the trunk (I'll store them inside the spare tire itself), which made a pretty good storage nook for the laptop. it's a curved space, so I had to make a small brace out of particle board, otherwise the laptop and docking station tended to separate.
It's very easy to pop in and out, and all my USB devices are connected directly to the docking station - making removing it for access very simple.
Now all I have to do is permanently mount it, extend some USB cables up to the car stereo, and fix the audio (so that I get PC audio out of the stereo.). I do have additional audio inputs, so adding an xbox to the trunk should be super-easy. Plus, all the loose parts come right out for days at the track.