2 1/16 gauge ECM data display

[3400tZ]

I've always wanted a nice display to run inside my car and that's one of the reason I started working on Android apps. Clarion recently came out with the AX (http://clarion.com.my/ax1/), an Android based head unit. That was the first I was seeing from a decent head unit company, instead of those Chinese no name one. The main issue with that unit tho is that it's running Android 2.3.7 which is already over 2 years old. I really want Ice Cream Sandwich at the very least. I would assume 2 years ago is when they started working on this thing but they need to update it as it's already way out-dated.

So while I'm waiting for that nice Android based head unit to come out, I thought I would come out with an alternative solution for a permanently mounted display. This is when I thought I could turn my boring Voltmeter into something much more powerful. I will be replacing it with a gauge that will be reading data from the ECM over the CAN bus. I'm mentionning CAN bus because I'm running a MegaSquirt ECM and it will be a much better option then serial as it will allow me to keep the gauge connected all the time while still have access to the USB port on the MegaSquirt to tune / datalog. Also, the gauge being a CAN device will allow me to tune it using the USB port of the ECM. That way I can change the gauge display value or whatever gauge parameter with an Android device or netbook in the same tuning software that I use to tune / datalog.

Making this project fully customizable and working on any ECM (even any MegaSquirt) would take years so this will be mostly be an hard coded version for my specific application. I might start "unharcoding" some stuff at some point but it will take a while. The good news for you guys is that it will be open source so I really hope I will have a few person jump in and create an ALDL fork or something :)

I've done similar project in the past but using an LCD touch screen instead and let me tell you that the OLED screen seems to be a much better option for automotive use. The display seems to look good from any angle which is definitely not the case of an LCD screen (or at least the one I had).

Any one interested in this project ? :) I will keep updating this thread if you guys think this is an interesting project!

The OLED I got now is this one: http://www.adafruit.com/products/938

The code will be hosted here: https://bitbucket.org/SebGiroux/diyecmgauge/overview

Here is where I'm at after 15 mins of work:

[mikew]

Very nice.

If anyone is interested, here's a link to a couple of Arduino based 8192 ALDL loggers that I've built: http://www.xm381.com/xm381/aldl.html

Just like 3400tZ, mine is designed for my specific application a 1227727 ECU with $A1 code but could easily adapted to any 8192 ECU.

3400tZ has motivated me to look a little further into a gauge mounted logger for 8192 ALDL.

I suspect 160 baud should be quite doable too.

My projects use a hardware serial port but I think one of my next step is to build an 160/8192 communications library based on the softwareserial one.

[EagleMark]

I approve these projects!

Just kidding, this is way cool stuff guys!

[3400tZ]

Few more hours of coding:


I have a few issue now tho.

The first one is that I'm maxing out pretty much everything on the Uno. I tried loading all libraries I want to use at some point (GPS and all), and I got this output from the compiler:

Binary sketch size: 18174 bytes (of a 32256 byte maximum, 56.34 percent).
Estimated memory use: 2416 bytes (of a 2048 byte maximum, 117.97 percent).

So It's maxing out the SRAM just loading the library, I haven't done anything with them yet.

So Uno definitely won't work. Flora is not gonna work either (I think they are 2.5k SRAM ?) I'm thinking about getting a Mega now. I was looking at the Due but it seems to be too incompatible with so many thing, it could be annoying. The Due is somehow cheaper then the Mega tho...

The issue with the Mega (or Due) is the SPI pins seems to be at different places then the Uno so I will end up having to do something like this:







So as you can see in the video, I'm currently using a push button to change page. It's way too sensitive now and I need some debouncing but it's a pain to do in the software as Arduino doesn't support calling millis() function inside an interrupt which is very annoying. So I will probably end up with a hardware solution by adding a capacitor, something like this:



The original plan tho was to use these two things:
http://www.adafruit.com/products/1096
http://www.adafruit.com/products/1391

As you can see on my video. The issue is that for some reason it doesn't work. When I got the receiver, only half the pins were soldered on the PCB I went ahead and soldered everything but maybe I shouldn't have done that ? Anyway, its cheap enough, I will order another one next time and see how it goes. It would be cool to control the gauge with the remote instead.

I've commited the code in the bitbucket repo I posted the link above if anyone is interested, but so far, it's a mess. :)

[steveo]

i'd like to see the code, but it appears that your bitbucket repo is private

[mikew]

Looking good.

I'm sure you know this; the Meg2560 and the newer UNO's both have an 6 pin ICSP header (for SPI) in a common location, but it looks like your CAN bus shield was designed for the older style boards since it doesn't have those connections (unless they are surface mount on the bottom of the board).