Headunit base system

Features

• Media playback via USB and BT
• FM Radio
• OBD diagnostics from car
• Android Auto integration

Requirements

Hardware:

• Raspberry Pi 3 or better (Android Auto won't work fluently on RPI2, the rest might)
• Official RasPi touchscreen
• External Soundcard and BT adapter (for Android Auto)
• RTL-SDR dongle
• OBD2 Adapter

Software:

• Raspbian OS based on Debian Wheezy
• Python3

Installation

Please note: These installation instructions are written mainly for my own purposes. However, with little customization of the code (e.g. changing the address of you obd2 adapter in main.py), you can get it running on your system as well. If you are in need of any assistance, feel free to open an issue.

First build the following packages:

aasdk: https://github.com/openDsh/aasdk
OpenAuto: https://github.com/Cacaonut/openauto
TCPBridge: https://github.com/Cacaonut/tcpbridge (using python3 setup.py install)
bluetool: https://github.com/shoeffner/bluetool (using python3 setup.py install)

Then install it:

sudo apt-get -y install python3-pyqt5 python3-mutagen rtl-sdr libatlas-base-dev minicom python-serial
pip3 install pyrtlsdr numpy scipy matplotlib ipython jupyter pandas sympy nose rpi-backlight python-uinput

git clone https://github.com/Cacaonut/headunit-base

Configuration

Allowing screen brightness adjustments

echo 'SUBSYSTEM=="backlight",RUN+="/bin/chmod 666 /sys/class/backlight/%k/brightness /sys/class/backlight/%k/bl_power"' | sudo tee -a /etc/udev/rules.d/backlight-permissions.rules

Enabling Bluetooth audio streaming

Open the bluealsa configuration file:

sudo nano /lib/systemd/system/bluealsa.service

Edit the line starting with ExecStart and edit it to match below:

ExecStart=/usr/bin/bluealsa -p a2dp-sink

Fixing bug that leads to sound cutting of on low volumes

Open the pulse audio config file:

sudo nano /etc/pulse/default.pa

Find the line starting with load-module module-udev-detect and append ignore_dB=1.

Changing device name

Create a file called machine-info:

sudo nano /etc/machine-info

Fill it with the following content:

PRETTY_HOSTNAME=[device name]

Configure autostart

Open the lxsession autostart file:

sudo nano /etc/xdg/lxsession/LXDE-pi/autostart

Add the following line:

@/usr/bin/python3 /home/pi/headunit-base/main.py

Disable bootup messages

Open the boot cmdline file:

sudo nano /boot/cmdline.txt

Change console=tty1 to console=tty3 and add logo.nologo loglevel=3 vt.global_cursor_default=0.

Change splash screen

Open the boot config file:

sudo nano /boot/config.txt

Add the following line to disable the gpu test resolving in a rainbow screen:

disable_splash=1

Create a custom image matching your screen size and copy it the the following location:

sudo cp ~/my_splash.png /usr/share/plymouth/themes/pix/splash.png

Disable screen blanking

Open the start menu, then go to Preferences, then to Raspberry Pi Configuration. In there select Display from the top bar and disable Screen Blanking

Disable mouse pointer

Open the LXDE configuration file:

sudo nano /etc/lightdm/lightdm.conf

Search for the line starting with x-server-command. Uncomment it and add -nocursor to the end of it.

Change permission for uinput directory

Execute the following command:

sudo chmod 777 /dev/uinput

Restart

IMPORTANT: Don't forget to restart your Pi after making configuration changes!

Run

If you haven't configured autostart, you can run it manually.

python3 main.py