Tuesday, September 23, 2008

Zune Project: Part 1

Over a year ago the in-dash 6 cd changer started having problems in my 2001 Nissan Pathfinder. Cds would get stuck, couldn't be read, until finally "ERR2" stayed on the screen and wouldn't go away. I went to some forums and learned that it was a common but expensive problem. I decided I didn't like CDs anyway and I wanted to rely on my Zune (microsoft's mp3 player) for my music. 

I had tried using one of those radio transmitters before without much luck (I've since soldered a wire to the the antenna to increase it's range, see instructions here), and the tape player on the head unit was screwed up so I couldn't use one of those tape things.

Luckily, the head unit has an auxiliary input in the back. I bought the harness for $49 at ActiveTuning (link), tore out my cd player, installed a little in-dash shelf ($20 at best buy), and hooked up the harness. The harness comes with a switch to go back and forth between Aux and regular modes, and I just popped out one of the square hole covers to put the switch and audio cord through. The pics of that setup are below:

It sounded great, and I liked almost everything about my big switch from cds to digital - except one tiny detail. I had gotten used to skipping tracks, and play/pause functions on the Nissan steering wheel. These worked with the cd player but obviously not with the zune. Conveniently, there was one steering wheel button for skipping tracks that did nothing while the stereo was in AUX mode, so I decided to find a way to at LEAST skip tracks but hopefully also to play/pause the zune using the one available button (two of the remaining buttons were +/- volume, which did work with the zune).

I started by looking in to the pinout of the zune to see if I could work out something that could directly control the zune through the connector. I found out that 1) there are a lot of freakin pins (24 of them) that are really close together and 2) people hadn't figured out what half of them are for (link). I wasn't about to try and tackle that can of worms.

The solution I finally came up with was to mount a zune dock somewhere in my car, and program my own customized remote control that would be triggered by the buttons on my steering wheel. Luckily, after Apple came out with the iPod Touch all the zune stuff was dirt cheap. The docks were down to $10 from $40, and the remote controls that went with the docks were only $8. I bought two docks, 1 remote, and got to work. 

The first step was mounting the dock in my car. I eventually settled on mounting it to the ash tray, since it had a nice area to stash whatever electronics would be needed. To mount it, I popped the cover off with a small screwdriver and took out two of the screws that hold down an internal weight. I drilled through with a 1/8"  drill bit, all the way through the other side, so that I could put long screws through. The red arrows in the picture below show where I drilled through:

I drilled the same two holes in my ash tray so that I could put long 4-40 screws through, and fastened it down with nuts. Ignore the LED in the pic below (that came later):

The complete setup is shown below:

At this point, nothing was really any different from before the dock, but it did give me a place to put the Zune while I was listening to music. I was able to plug the 1/8" plug into the back of the dock, and the dock plugs in to the cigarette lighter. Overall it was an improvement from just sticking the zune in to the shelf.

Next post I will show how I got the steering wheel interface to work.

Monday, September 15, 2008

Hello world

Well I've been meaning to make some kind of website about my projects for quite some time now... my last attempt did not get much further than a nice template. You can see it here. It's been about a year since I did anything with it.

I have a problem with finishing things... once I learn enough to do it, a lot of the challenge is gone and I lose interest. That is why I stopped working on that website (it took a few hours) but it is also why I started this one.

This blog is all about documenting the few projects that I have actually spent the time to finish without losing interest. I hope that it serves two purposes. First, it provides a place for me to share my projects with others. Second and more importantly, I'm hoping that it will help me follow through with other projects that I might not otherwise.

To start this thing off, let me just list off some of the projects I might write about that I've finished over the past few years.
  • Control Zune mp3 player with steering wheel button using a dsPIC (just finished, September '08)
  • Folding basket opener/closer made from acrylic (finished March '08)
  • Automated solver for minesweeper-like game using AutoHotKey and Matlab (finished April '08)
  • Automated game playing program for a fun little web game called cyrkam airtos (finished October '07)
  • One legged balancing robot, master's thesis at UCSD (finished June '07)
Timeout, I really don't want to write anything else about my thesis. I already spent countless hours building and controlling the thing, and wrote 140 pages on it. A link to my thesis is here, and a youtube video is here:

Moving on...
  • Puzzle solver for an obscure online game using Matlab (finished around Jan '07)
  • Magnet hovering apparatus (finished in late '06 I think...)
  • "Worms" simulation using VBA in Excel (finished summer of '06)
  • Puzzle solver for a sudoku-looking-but-far-from-sudoku game called Picross, using VBA in Excel (finished sometime in '05 I think)
Well I've probably gone back far enough with this list. Of course there is more, but my memory is bad and I'll probably only elaborate on half of the list as it is.

Let me finish this off by saying that this blog is not about me, it is about my projects. Although I'm sure that writing about the things that interest me will inevitably paint some kind of picture about me, I'll try not to fill in the blanks myself.