OBDuino working with ELM327 (pix + movie)
 

Yesterday I made my first real test with the OBDuino connected to my car, and it worked :)

Here is a picture at idle, note that the display is in L/h because speed is 0.
http://opengauge.org/~obduino/hardware/OBDuino_idle.jpg

I also made a small movie, but in my code I had a problem with a value being signed so sometimes the fuel display goes negative (I corrected it in the trunk code).

http://video.google.fr/videoplay?doc...96121009912634

Unfortunatly it seems google resized the movie to 320x240 :( and I was taking it with my digital camera while driving so quality is not very good, but at least it shows you the thing. I display fuel consumption, speed, RPM, load.

Nice! I love the low quality background music.

Thanks, and sorry for the music, this was the radio but the volume was low, I didn't know we would hear it, I should remove it from the video :)

Yay keep it up!

I would make one of these with a larger display, to be able to look at six or eight gauges at a time. That would be sweet. I think you guys are onto something here. Good luck and keep us posted.

I added menu configuration, you can now configure LCD contrast and if you want metric unit or imperial.

I also added "virtual" screens, there is 3 screens, each displaying 4 infos, you rotate through them by pressing a button. It makes 12 infos available quickly. I will add them in the configuration too.

Buttons act like this:
BTW here is my ELM interface:
http://opengauge.org/~obduino/hardwa...face_front.jpg

random pictures:
http://opengauge.org/~obduino/hardware/idle_si.jpg
http://opengauge.org/~obduino/hardware/idle_imp.jpg
http://opengauge.org/~obduino/hardware/in_car.jpg
http://opengauge.org/~obduino/hardware/in_car_night.jpg
http://opengauge.org/~obduino/hardware/contrast.jpg
http://opengauge.org/~obduino/hardware/unit.jpg

Hi,

Check tihis post i did, your wish is on the way :)

http://ecomodder.com/forum/62481-post217.html

hello guys....

i'm looking for a display to show how much gasoline my car is using...

i built the elm 327 scanner last week and i think that this will work perfectly....

so, where i can get the projects to build a display like this?

thanks.

marcelo.

If you have a serial ELM327 interface, I think you just have to plug it to the serial plug of an Arduino clone. I don't know if you need a straight cable or a cross one however!

If you have a USB version you will have to wire pin 16 of the ELM327 to pin 1 (TX) of the Arduino and pin 17 of the ELM327 to pin 0 (RX) of the Arduino.

Project is described here
OBDuino - opengauge - OBDuino Description - Google Code

ow god.....there is a lot of the freeduinos and other duinos.....what of them i need to use?

is it possible to buy the atmega chip then build the arduino? Is there any kit to buy?

my car is a ford with pwm protocol....the elm327 is connected on the pc serial port.

so, do you know exactly the model that i have to buy?

thank you a lot....

marcelo.

i think that i found......

can you confirm that are the right kits?

Freeduino Serial v2.0 board KIT Arduino Duemilanove Compatible

and

16x2 LCD Module White Characters Blue Backlight

i need to buy something else?

thank you.

This board is ok, this is the one I use, very easy to build.
The LCD is ok too, and you need a transistor and a resistor to drive the LCD brightness, and 3 small push buttons too, I think that's it.

Magister,

Will your CAN interface work with other protocols? I have a 99 Saturn that I am sure is not ISO or CAN. I assumed no because you have the SAE pins of the ELM327 going to ground. I also have a new ford that uses CAN and an old civic that uses ISO, if possible I would like to be able to transplant it to all three.

Thanks

The ELM327 support all protocols but you will have to build the full ELM327 interface as described in their PDF if you want to use it in iso/can/vpw/pwm cars. I only wired the CAN parts for my car.

will the obduino32k work correctly without modification if I can get the full interface built? The reason I am asking is because I am in no way qualified to modify any type of code. I am your average joe mechanic trying to follow this project and it is turning out to be a learning experience.

It's been a long time I touched the ELM code and there was a lot of checkin for the ISO code, I hope it didn't break anything.

The ISO interface works nicely with the mc33290 chip in my 99 civic. I would just like to have one that I could move from vehicle to vehicle.

I promise we did our best not to break anything.

If something doesn't work it should only be easy to fix. The obduino32K code should be trustable enough to go ahead and order the Chip

electromike,

I will go ahead and order it then, possibly two in case I screw something up. My only other worry is the interface for the chip. It looks much more difficult to build than the one for iso and with my extremely limited electronics knowledge, it should prove to be a serious challenge.

ELM provides schematic, PCB design and even the gerber files for their interface, you could use them to help you build the interface

ELM Electronics - Chip Help

take a look at the "Where can I buy a circuit board for my ELM IC" paragraph

well,

I finally bought the duino. now, i need to build everything.

so, i was reading the tutorial code.google.com/p/opengauge/wiki/OBDuinoDiagram and there is nothing about my car's protocol.

my car is a 2000 year Ford with SAE J1850 PWM protocol. on that tutorial i saw ISO and CAN protocols.

I have an ELM327 interface working on my computer, but, how i need to plug the led display on the freeduino?

i bought this nkcelectronics.com/freeduino-serial-v20-board-kit-arduino-diecimila-compatib20.html and this nkcelectronics.com/16x2-lcd-module-while-characters-blue-backli162.html

thanks a lot by the help....

Your ELM327 interface is a closed enclosure? if it's the case you have to put a "NULL modem", a cable with TX/RX crossed, between your ELM interface and the freeduino. For the LCD there is a diagram on the wiki of the project
OBDuinoDiagram - opengauge - Whole diagram of the Arduino board, LCD, interface - Project Hosting on Google Code

i assembled my elm327.

i dont understand yet. here code.google.com/p/opengauge/wiki/OBDuinoInterface there is the interface with elm327 but the PWM protocol dont is used.

the pins 3, 4, 11 e 13 of the elm327 chip are not used on the diagram above. i must to buy the MC33290 chip too? the PWM will be converted on CAN protocol?

i am lost :confused:

but, again, thanks a lot by you help.

I assumed you have a full ELM327 interface, bought from eBay for instance? If this is the case then everything is inside to support all the protocol.
If not you have to built around your protocol with the various components needed, transistors, etc
A quick google find this:
http://images.forum-auto.com/mesimag...ns%20titre.jpg

yeap. I bought the ELM327 chip and assembled to all protocols. and it is working ok, but only on my computer. I think that is just plug the serial port of the ELM scan to serial port of the arduino. i think that is ok.

my problem is to put the LCD display on the arduino. how i need to connect the wires? which ports? on which pins? i need to buy the MC33290 chip? i just use this image opengauge.org/%7Eobduino/diagram/obduino.gif?

Yup I think it's the right diagram.

In the code it says :
#define DIPin 4 // register select RS
#define DB4Pin 7
#define DB5Pin 8
#define DB6Pin 12
#define DB7Pin 13
#define ContrastPin 6
#define EnablePin 5
#define BrightnessPin 9

it seems ok to me

i found what i wanted.

Arduino - LiquidCrystal

let me talk what i think about connect the arduino with my car and you can say if there is right or not.

I have the elm327 working. I will to assemble my arduino kit with LCD 8x2 like the schematic on the link above. After this, I will write a program in C/C++ to connect the arduino's serial port to elm327 serial port and read rpm, speed and so on.

Its right or I am entire crazy now? hhahahhaha....:D

thanks for you patience

This is what the OBDuino is doing, just connect your LCD as the diagram, and load the sketch in the Arduino IDE, compile, upload

obduino32K.pde - opengauge - Project Hosting on Google Code

uncomment the define ELM and comment the define ISO before compiling.

Also I don't remember if you need a crossed cable between the serial port of the Arduino and the ELM327 interface or a straight one!

hum......ok.....the code seams to be all that I need....great heheh..

i will assemble the lcd and arduino on this weekend. maybe i need some help ahead.

thanks a lot.

How can I interface this thing with the Arduino board?
$25.90 - ELM327 USB Vehicle OBD-2 Scanner Tool - OBD/OBD2 Car Diag. Tools

This device being USB, I doubt you can. You would have to open it and check if they use a PIC with integrated USB (which is certainly the case), in this case you can not.

http://opengauge.googlecode.com/svn/...obduino32K.pde

I'm trying to use this code for use with a serial cable - while compiling I'm getting errors. I'm using Arduino 22. I'vce little knowledge with programming, so please help me out

Maybe this late, but I just started making my OBDuino.

I'm using the device from dealextreme:

It contains the elm327 with all necessary peripherie and an FT232BL.
The FT232 chip ist just an "virtual COM Port to USB"-Chip.

So you just have to wire your arduino to the RX/TX Pins of the FT232 and then the OBDduino will work!! Oh don't forget to connect ground :)

Pictures + Videos coming soon...

Great project! will be trying this.

One important point i did not mention is that the elm327 in dealextreme device is working with 38400 bau not 9600 baud. So you have to modify the elm_init function

from:

serial.begin(9600);

to

serial.begin(38400);

Hi, I am interested in doing the same thing, cand you send me the link to the dealextreme product page please

I'm not allowed to post links but it's the device archas mentionted a few posts before...

the sku is 28528

This is the device i used...

hi, just got the dealextreme elm, trying to compile de code, but i get errors, do i need to comment/uncomment thing (exept #define elm327) to make it work?

is there a step by step instructrable version you can post to create your own obduino?

Thanks in advance!