2 1/16 gauge ECM data display

**EagleMark** · 11-10-2013

I approve these projects!

Just kidding, this is way cool stuff guys!

**3400tZ** · 11-11-2013

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** · 11-11-2013

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

**mikew** · 11-11-2013

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).

**3400tZ** · 11-12-2013

steveo, sorry about that, I'm was pretty sure I created it public from the beginning. Oh well, now it is, let me know if you have any issue.

Mike, yeah both CAN bus shields that I know of don't have the ICSP header. To make it worse, SparkFun does sell this thing https://www.sparkfun.com/products/11469 that I think would work to change the pin out back to "normal" but I'm not 100% sure it will work fine with the Mega and it has no holes that I need for my enclosure (https://www.sparkfun.com/products/10088) that seems to be a standard for arduino stuff. So I found this shield instead https://www.gorilladistribution.com....uct/leoshield/ that does seems to be a better option. So now I'm trying to go back to sparkfun to look for an enclosure that could possibly contains two shields and their site down for maintenance for a few hours... fun fun fun :D

It seems like everything is incompatible with something, its a pain in the a** :D

**EagleMark** · 11-12-2013

Originally Posted by 3400tZ

So now I'm trying to go back to sparkfun to look for an enclosure that could possibly contains two shields and their site down for maintenance for a few hours... fun fun fun :D

It's the Obamacare website virus...

**Six_Shooter** · 11-12-2013

Originally Posted by 3400tZ

It seems like everything is incompatible with something, its a pain in the a** :D

Which is why I don't rely on shields, I just breadboard it.

I have one shield that I bought when I bought my Uno, for the LCD, because it was simple and it made it easy to do some of the basic LCD stuff I wanted to do.

If you're looking for alternate gear look at the Teensy, it's very much like the Arduino, even uses the Arduino IDE, but seems more powerful, IIRC. I have a Teensy++ 2.0 and it's nice, especially for for plugging into and using a breadboard for development.

www.pjrc.com

**Six_Shooter** · 11-12-2013

I just spent a few minutes verifying that the Teensy++ 2.0 has 8kB of SRAM, referred to simply as "RAM" on the PRJC site.

http://www.pjrc.com/teensy/index.html

Atmel page (the Teensy uses the 1286 uC):
http://www.atmel.ca/devices/AT90USB1...tab=parameters

Did I mention the Teensy is cheaper than the Arduino?

**3400tZ** · 11-12-2013

Yeah, my problem is that I don't really know what I'm doing in term of hardware :P I think I will buy that "LeoShield" and an Arduino Mega because I know all that stuff will work together out of the box. I don't mind buying some Arduino hardware as I know this isn't the last little project like that that I will do so it's always nice to have some stuff already laying around.

I haven't forgot your offer to create a proper PCB tho :) I was thinking it could be cool to maybe eventually sell a nice PCB for that project as well as some open source libraries that are already working for MS/ALDL/ODB2 as a DIY data display gauge type of project. I bet some people would be interested in that!