Following Paul’s tutorial , we detail the steps to make pcDuino display car diagnostic (OBS_II) data. In this post, you will learn how to use Bluetooth 4.0 USB dongle on pcDuino, and use it to connect to OBD-11 adapter to retrieve real time engine data and display them.
Locate the SAE J196216 (OBD port) connector on your car, which is usually in the drivers cabin. The following is a picture of the ODB connector.
Connect the ELM327 OBD2 to the OBD connector:
On the pcDuino side, we need to connect the Bluetooth 4.0 USB dongle to pcDuino3 USB port. We can use a USB hub if the USB port is not enough.
The software installation is pretty straightforward. First, we need to run:
$ sudo apt-get update
Next, we are going to install the python and Bluetooth tools:
$sudo apt-get install python-serial $sudo apt-get install bluetooth bluez-utils blueman $sudo apt-get install python-wxgtk2.8 python-wxtools wx2.8-i18n libwxgtk2.8-dev $sudo apt-get install git-core
To download the OBD python code, we use the following command:
$ git clone https://github.com/Pbartek/pyobd-pi.git
Bluetooth Pairing and Serial Port
Now we are going to look at how to pair bluetooth. Before we do that, we need to run ‘$su’ to switch to root user. Please refer to this post if you don’t know how to do that.
We navigate to the menu, and select Bluetooth manger:
Right click the first device, and choose ‘Connect’. It will show up as:
Now right click the OBD11, and click ‘Pair’. It will ask for password, please enter ‘1234’. After that, right click OBDII again, and click ‘Port’:
Now the buletooth serial port is accessed as ‘/dev/rfcomm0’.
Run OBD GUI:
To run OBD GUI, we just do:
$ cd pyobd-pi $ python obd_gui.py
The following is the screen displaying the data: