The Raspberry Pi foundation did something weird, and all Raspberry Pi model A+ disappeared from the market. I could not order anything.
A month later they announced a new board – the Raspberry Pi Zero. It was great except it was also made from unobtanium. I managed to get a grand total of one from an eBay scalper.
Anyhow, I had to design a new version of the CD-changer emulator which worked with the Raspberry Pi Zero because it looked like the days of the A+ model were numbered.
So this is the first board I did, which was just a bit bigger than the Zero itself. On the image, you can see the board in a new box for it. The Pi Zero is MIA.
Also, my SMD soldering skills have improved slightly.
Ready to be dispatched to it’s new owner unit #27.
This was one of my favorite color combinations for the box of the CD-changer emulator device. This version has vents on the side – not because the device was overheating, but the box was easier to print this way. Without the vents, the ABS plastic would curl up, and the box looked very weird.
With this particular unit, I had some trouble with the optical connector not locking to the plug and had to improvise with some wire to hold it in place.
By the way, this re-design of the unit box was prompted by customers returning the device in half-melted form. In the initial version, the box was printed out of PLA which was getting soft in the summer temperatures in Texas and Arizona.
So I had to print all plastic parts our of different plastic – ABS, which has a higher melting temperature.
This is one of these projects that I never finished. I managed to hook up the Jaguar navigation unit to the Realtek LCD controller board and in turn to an old 14″ laptop screen.
I had to tweak the Realtek firmware a bit to accept the video signal from the nav unit, but you can see it was working fine.
The imaginary goal was to replace the LCD screen in the factory unit with a better resolution screen. However, in the process, I was not able to find anything I liked with a side that would fit the Nav unit and would not require major surgery.
In the end, it was a cool thing to play with, but never saw the light of day. Here are a few more pictures of the Nav UI.
As you can see the 14″ screen does not have the correct aspect ratio – the circle is a bit squished.
Here are a few pictures of a screen I was considering as a replacement of the factory unit, but in the end, it was just a bit too big.
Just for fun, I made this contraption. Connected an old Sony laptop screen to an HDMI control board (Realtek 2660) and “voila” a 9″ LCD monitor for my Raspberry Pi.
A few more pics here.
The best part was the copious amounts of scotch tape to hold things together.
I created a programmer for the Realtek board, so I can swap the firmware with one that was suitable for this screen size.
My gracious “beta” customers returned their units, and I provided them updated devices with the “final” form factor.
This allowed me the opportunity to take a picture of the “beta” version of the CD-changer emulator unit.
You can see that the fiber-optic connector is a separate board. Initially, I designed it like that because I was planning to have a version for Jaguar cars as well as Mercedes-Benz cars. The only difference between them being the optical connector. It did tun that the Benz people are far less enthusiastic about the product, so I simplified the “final” board with the connector onboard.
In this version, the Raspberry Pi was on the side of the control board, and there is a whole lot of wires going around.
The final version was much more compact and easy to make.
I was very happy reaching this point. I was quite a few years of effort, but finally, here it is. Something I can offer to people – a useful product. A device which emulates the car CD-changer and lets you stream music from your phone via Bluetooth.
Following a short beta test period, this is the re-designed look of the CD-Changer emulator. The fiber-optic control board is now on top of the Raspberry Pi. You can see the fiber-optic transmitter glowing in red through the connector plastic housing.
The board says V3.0 because V1 was the “beta” device and V2 never saw the light of day. The board has the D2B controller OCC8001 as well as a Cypress ARM M0 micro-controller and finally power supply circuit.
Here are a few more pictures.
Naturally, I misspelled the URL on the board, should be iQury.us. Brain does not function as well as it once was I guess.
I could not locate any source to purchase the fiber-optic connector used in Jaguar cars, so I 3D printed one.
I managed to find an optical transmitter and receiver pair working at around 650nm wavelength. They were compatible with the signal in the car, so here it is optical connector replacement in all it’s glory.
Very simple homebrew fiber optic “loop” cable. The D2B devices have to form a loop and this little gizmo comes very handy if you have to disconnect a device – just plug the loop in the empty fiber optic socket.
The connector is 3D printed, the optical “cable” is cut from SP-DIF (aka TOSLINK) cable – they use the same 1mm plastic fiber core.
This is one of the first working prototypes. The box has a Raspberry Pi model A+ which does audio streaming over Bluetooth. I covered the box with copper foil to try an minimize the EMI interference.