But I have made progress on the CarHUD. Quite a lot in fact.
As I last wrote, I gave up on the LCD projector idea and moved over to a dual 4 digit 7 segment LED array from Adafruit.
I also acquired 2 Pi Zero's since I last updated the blog.
You can probably see where this is going.
I decided to swap out the Model B Rev1 with the new Pi Zero. This was done in an effort to make everything more compact. I also didn't like how I had soldered the OBD-II board to my prototyping PCB.
First I did some testing.
Then I desoldered a bunch of stuff and re-soldered everything back into a new setup for the Pi Zero.
This is a bench test of the Pi Zero setup without the GPIO buttons for mode and brightness changing.
This is a full up, in car test, getting data from the OBD-II port.
Now you're probably saying to yourself, what about the OS? When I thought about using the Pi Zero in the CarHUD setup, it was about 2 months ago. I tried running my Yocto build of CarHUD OS on it, and it failed miserably. So I tried building it with my checkout of Poky's Dora branch. Still didn't work.
Fast forward a month and I search again for Yocto on the Pi Zero. This time, I'm successful. I come across this link: http://www.jumpnowtek.com/rpi/Raspberry-Pi-Systems-with-Yocto.html.
Basically it's the normal guide, but updated with awesomeness. So what do I do? I fork his meta-rpi branch into something I customized for the CarHUD. It's here: https://github.com/xtacocorex/meta-rpi.
pycarhud and pyelm327 are still alive and well on BitBucket. I pushed commits to pycarhud today as I got more stuff working. meta-carhud is probably going the way of the ghost.
I'll end with a couple of links to the system working:
https://www.youtube.com/watch?v=LmRZrQ55Ob8
and
https://www.youtube.com/watch?v=eOhZsKN1oYw