Corvettes have a trunk... who knew.
So it still isn't completely done but almost there.
Corvettes have a trunk... who knew.
Ok, for the final part of the install, I wanted to put in steering wheel controls in the car. Now, the 2006 Z06 did not come with steering wheel controls nor did it come with the wire to do it after the fact. However, starting in 2008, IIRC, the Z06 did come with the steering wheel controls for the stereo on the right side spoke. And in 2009 I believe the blue tooth option was added and those controls were on the left side of the spoke, Now, the problem I had to solve was how to make the controls interface with the PC to control volume, answer the phone change the current music track…etc.
First I needed to get a hold of some of these controls and find out how they were designed and how they worked. So I picked some up from the chevy dealer…couple sets actually. I popped one apart and did some analyzing of the circuitry inside and found that there were only 4 damn wires that controlled the 7 buttons and two of those wires did the backlighting on the buttons. So that left a 2 wire control for 7 buttons. At this point I realized that this had to be a voltage ladder type arrangement. That basically you supply a fixed voltage down a series of resistors that ends in a ground. When you press a given button that completes the circuit at a given point in the ladder and returns a voltage. That voltage is essentially a fixed value that can then be read by the return circuit and the button can be identified and the function executed.
Great, now I know how it works, I just need to turn that into an interface with the computer. So I started working and a circuit that compared a known voltage to that of a button press and that, in turn would send signals down stream. Now you might say, why not use a microprocessor like a PIC or Atmel chip? That would be the more elegant way of solving the problem. However, one little obstacle is I don’t know how to write firmware for the micro and I knew it would take more time to learn than it would to do by brute force (at least for me). So I choose the brute force method of using voltage comparators, Hex inverters and AND gates for my project.
So I designed and started to test the circuitry to control the steering wheels. Here are a few shots of the prototype board I made:
Now, I came across another issue and that was I needed…well WANTED…more than just 7 buttons for control. I had ideas to control the radar and laser detectors/jammers as well as the monitor and possibly some other controls for other little devices. I needed a way to alter the function of the buttons. Turns out I found a solution using some data switching chips and a need little signal chip from microchip. This additional circuitry allowed me to have 4 banks of 8 switches. The only issue was I needed to be able to toggle the additional switch banks. The way this works is to turn on and off different signal chips. As you toggle from 1 to 2 to 3 to 4 and then back to bank 1. When you start the car, you are on bank 1 by default. As for the toggle, I choose to use the paddle shifters used in the C6 automatic triptronic type transmission. Turns out they are a 2 switch and 2 wire voltage ladder as well. So these were integrated into the circuit using the finger paddle as the switcher and the thumb as the 8th switch.
From there I needed a way to switch various signals from low voltage low current to higher voltage and up to 1 amp in current. I choose a type of optoisolator for this task.
Here’s a few picture of the final circuit:
In order to make this work, I had to replace the clock spring on the steering column. For those that don’t know what this is, it’s a springy type flat cable inside a plastic housing that allow you to turn the steering wheel without tangling up any wires. There are connections to the wheel and on the column but keep the regular wires from getting tangled. I also need to redo the harness along the column to accommodate the new wires but still allow the horn to be wired in properly. I then have to wire to the computer. I used a little device called UHID to convert the button presses to keyboard strokes that will then control the various function in the front end software. I also wired in the controls for power to the Laser and Radar detectors so I can control them turning on and off. I also wired in the Valentine One mute button.
On a final note for this post, I and another car nut developed a circuit that will show the V1 and Escort 9500ci detectors in the Heads Up Display. So I have this information in my HUD and the V1 blanked.
---------- Post added at 11:28 PM ---------- Previous post was at 11:21 PM ----------
A couple pictures of the buttons and paddles in place:
Don’t have any better pictures than that. I’ll have to take some of the entire interior here in the next couple of days.
Also, got the second sub box roughed up and fitted in. However, it’s not going to work as both a sub box and PC cooling fan platform. I’ll go into why in the next post with some pictures of the box.
so did you etch/coat the boards yourself, or did you have it sent out somewhere?
My OLD 2001 Mitsubishi Eclipse GT:
"The Project That Never Ended, until it did"
next project? subaru brz
I had them sent out to a board house. I did my own etching years ago but it would typically take 3 times to get one good board. Fine traces, fogedaboutit...not happening.
I've gotten pretty good at laying out my own boards. However, my designs are pretty simple in nature, I don't really have to take into account much for RF shielding or generation or those types of things that more complex circuits and designers have to deal with.
And I thought my install was complicated, WOW! Very nice indeed. I will be keeping my eye on this thread. Impressive creaseguard!
Last edited by RAWPWR; 04-16-2011 at 09:12 AM.
Thanks for the compliments to all. This brings us up to date where I am now with the car. Last week I ran a few tests with the other sub box and found that our cooling solution was not adequate at temps in the mid 80's. This led to the conclusion that during the very hot times during July and August, I was going to be having some major cooling issues and possibly some equipment issues with the heat. As such, we decided to forego the second sub and use that box as a conduit for the fan to draw cool cabin air and run it over the pc. What we also hope to gain as a secondary benefit is forcing some air across the amps and out the front edge of the false floor right behind the passenger and driver.
Once I have the second box in, the floor painted and mat made, I will post up some final pics of the install and the interior.