Author Topic: The "CD43 Face on a JVC HU" Thread - Work in Progress (Read 9858 times)

bmwman91 · « **on:** November 29, 2010, 01:45:00 AM »

Some of you saw my brainstorming thread about putting a CD43 faceplate onto a newer, somewhat more capable head unit.
http://www.r3vlimited.com/board/showthread.php?t=188611

Well, I have selected a HU and am actually working on the technical aspects of this now. I'll be posting progress in here, as I make it. The HU is a JVC KD-HDR60.

Right now, I have figured out one half of the electrical / programming side. It took some snooping around to get the data sheets for the LCD controller in the JVC HU, but once I did that it was a fairly simple matter of figuring out which data bit corresponded to which LCD segment (195 segments, 195 1's or 0's to turn each one on/off). I did this with my favorite microcontroller in the world, the PIC12F683. The windows UI was done in Visual Basic.

Pictures are more fun, so I'll toss some in. Here's the setup I was working with to debug this. The LCD was being manipulated through this simple little guy...a PIC12F683 uC, a 5V regulator & a DS275+ RS232-TTL level converter (so the PIC can talk to the PC). The LCD controller just uses a simple 3-wire SPI interface.

I soldered leads onto EVERY pin of the faceplate connector just in case I needed to check power-on timing or anything. Really though, I just needed the 3 SPI pins & a ground.

Just in case anyone wants "proof" of my nefarious plan to hack crappy car electronics for purposes of world domination...:p

As glamorous as that may seem, it took a solid 90 minutes of hitting the space bar & some arrow keys, and clicking the same button in a windows app to get enough information to do that. I printed out part of the service manual with the LCD section displayed (how convenient!) and checked every single segment. "But bmwman91, why are you messing with the JVC LCD? You wanted to put the CD43 LCD on there right?" Correct. I need to have the display data that comes from the JVC motherboard 100% understood first so I can translate it for the CD43.

This is a screenshot of the UI I made to debug the LCD.

A gratuitous scope shot...
This is the data packet my PIC sent the HDR60 to display "iAM BMWMAN91". The top trace is the chip select line (set it high when you want to tell the LCD controller, "hey I am sending info"), the middle is the clock & the bottom is the data line (the clock signals the controller to read a 1 or 0 at that time). The controller takes 256 bits in, 204 of which are for switching LCD segments and the rest are either for control purposes or unused. It is done in 4 64b sections with an address byte in between. Why? Who knows. It seems a little more complicated than necessary to me.

I'll do my very best not to get more technical than this since it won't really add anything to the story. If anyone wants more of the gory details, I'll be happy to post them (time permitting). My turkey day break is over tomorrow, so progress will probably slow down a bit since I'll be back at work.

DesktopDave · « **Reply #1 on:** November 29, 2010, 07:27:34 AM »

That is stunning. I am speechless at the keyboard.

Hey-u · « **Reply #2 on:** December 15, 2010, 03:09:54 PM »

Completely over the top. I love it.

bmwman91 · « **Reply #3 on:** December 25, 2010, 12:51:24 AM »

Progress...

I have all the key & display bits worked out for the faceplates. Now I need to make sure that I can physically fit them together in such a way that they can still fit into a single-DIN slot. After that I will start working on the circuit & microcontroller firmware.

Brief update...

I have been working on physically fitting it all together. Much to my dismay, the CD loading slots are in very different positions. Without modifying the HDR60, it would stick out ~9mm past the right edge of the faceplate. I haven't measured yet, but it looks like I have maybe 5mm to work with before hitting the OBC, probably more like 4mm. The only thing I can do is to move the CD transport assembly as far to the right as possible inside the HDR60 chassis, but I only get about 5mm before I hit the radio module. On top of that, there are some capacitors that are in my way, and the board-board interconnect will need to be modded. Maybe I should have measured FIRST lol. Worst-case, I just find someone with sheet metal tools & make a chassis!

bmwman91 · « **Reply #4 on:** December 25, 2010, 12:52:26 AM »

Quote from: Hey-u;99643

Completely over the top. I love it.

Hell yes. That's what I like to hear! Why put a functional radio in a car when you can hack up a bunch of them, spend months working on electronics and firmware, and have a stock looking radio in the end! lol

dude8383 · « **Reply #5 on:** December 25, 2010, 10:00:46 PM »

Oh man, I know somebody that would be all over this. Sending him a link to this page NOW.

MoMurda04 · « **Reply #6 on:** March 24, 2011, 03:03:00 AM »

Holy crap, great work. How much would something like this cost?

jscribble · « **Reply #7 on:** March 24, 2011, 10:58:55 AM »

Dude, you are AWESOME. 1337 credit!

bmwman91 · « **Reply #8 on:** October 17, 2011, 11:00:18 AM »

Alright, as promised, here are some pictures.

The biggest pain was figuring out how to move the board-board connector that connects the CD transport to the motherboard. I ended up lifting it and setting the ends on Kapton tape, and then filling the middle gap with super glue. From there, I ran 30ga wire from the original pads to the terminals.

Here is another angle. Once the wires were on, I filled everything in with more super glue. The last thing I need is this sucker breaking off if/when I need to take the unit apart in the future.

Although I had to leave a couple of components in place & buried under the connector, I was able to move this resistor out of the way, just in case I ever need to service it.

Now, to get the CD transport moved over, I needed to move its mount holes 1cm to the side. I used some calipers and a drill press to do this.

The only real mods I needed to make were to grind off an alignment post, and as seen in this picture, flatten the old stamped mounting boss. A bench vise & some aluminum blocks were all that I needed.

I also needed to press out some of the stamped screw holes in the side that the HD Radio module sat. The module had to be moved, and the screw bosses were interfering. Again, I used a bench vise & aluminum blocks.

This capacitor was interfering with a big one on the CD transport board, so I moved it over. It is a decoupling cap for the USB 3.3V supply. Although a setup like this isn't exactly ideal since I bet it adds some noise to the supply rail, I doubt it will be an issue. Long-term, I plan to find a big surface mount cap & replace this with that.

Here is the HD Radio module.I moved it as far to the side as I could. Remounting the EMI shield firmly to the board was a little tricky, and it is not quite as secure as before, but I think it will be OK.

I was able to move it over by flipping the pin header at the bottom. Originally, it was mounted through the side you see in the picture. Being a simple single-row through-hole header, it was a simple matter of de-soldering it from the RF board & mounting it on the opposing side.

It all worked out perfectly!

This also leaves ample room on the other side for my control circuitry. I don't think that there will (physically) be too much stuff to jam in there, but there will need to be room for a small PCB with the microcontroller & various control / power electronics.

I tested the JVC HU and the CD player + HD radio seem to be working fine. Phew!

I have been on vacation in Hong Kong / SE China for the last couple of weeks and have been using some of m down-time to work out various aspects of the microcontroller code. It is going to be a LOT of work, but that's the fun part anyway!

axisofjustice · « **Reply #9 on:** July 31, 2012, 01:41:24 AM »

Progress? Know it's old, but I love this concept! Have you considered upgrading and updating components in the CD43 instead of trying to use JVC guts? I would figure adding aux inputs and higher quiality components would be easier than this for similar payoff. ...Not that I am trying to take away from the overall uniqueness of this project you had going.