Hi, Here are the updates I have recently worked on: - migration to KODI stable 14.0 - Raspbian OS from 24 december 2013 - linux kernel 3.18.1 with touchscreen drivers - updates to Radio and Navigation addons
You can install the build using the tutorial link on the right side of the blog. Please don't forget about the forum for any comments.
After installing the image on an sd card, you have to configure the system for your needs.
Calibrate the touch screen The touch screen calibration involves two steps and you need a keyboard connected: 1. Calibrating the touch screen for X11 applications(like Navit). Open the terminal from Desktop and type xinput_calibrator and follow the indications. After the calibration is completed you have to put the output in a file to make this permanent: sudo nano /usr/share/X11/xorg.conf.d/01-input.conf Put here the output of xinput_calibrator. It will be something like: Section "InputClass" Identifier "calibration" MatchProduct "eGalax Inc. USB TouchController" Option "Calibration" "121 1917 317 1741" Option "SwapAxes" "1" EndSection 2. Calibrating the touch screen for XBMC. In XBMC use the keyboard to go to Programs/Touch Screen Calibration and follow the informations on screen. Note, that in order to make a better calibration you can move the finger on screen towards the point, before pressing enter(as can be seen on minute 0:52 in the video). Touch each point and then press enter to go to the next one. At the end, you have to unplug the touch from usb and then plug it back(works on XBMC Gotham). After this, he calibration is stored permanently in the file /home/pi/touchscreen_axes_calib. You can edit this file to fine tune the position of the cursor if the calibration isn't perfect. calib_x_d and calib_y_d - control the cursor displacement up/down/left/right calib_x_fact and calib_y_fact - some factors obtained in the calibration process(don't edit them) click_confines - defines the area that will be used for click(if the touch moves outside of this area then a drag action will occur) - this area is measured from the first touched point touch_mouse - if you want to use a mouse you have to set this to 0, but some touch screens behave as mouses and you have to set this to 1 in order for them to work(with single click). For the most of the touches this can be 0 if you want to also use a mouse, but if you don't want to use a mouse it doesn't mater, let it be 1.
Change the resolution [XBMC] Using ssh you have to edit the file /home/pi/.xbmc/userdata/advancedsettings.xml and set your resolution. After this restart the whole system and XBMC should run with your new resolution. [LXDE] Connect with ssh and type tvservice -mDMT && tvservice -mCEA and get the desired resolution mode Edit /boot/config.txt and modify according to your preference, for example: hdmi_group=2 hdmi_mode=27 CEA group is 1 and DMT 2.
Add a new map for Navit 1. Go to Navit Planet Extractor and download a .bin file for your area. 2. Copy the .bin file in your RPI card in /home/pi/.navit/ folder 3. Edit the file /home/pi/navit_src/build/navit/navit.xml and search for the entry: <mapset enabled="yes"> <map type="binfile" enabled="yes" data="/home/pi/.navit/Romania.bin"/> </mapset> 4. Add your map name here like this: <mapset enabled="yes"> <map type="binfile" enabled="yes" data="/home/pi/.navit/Romania.bin"/> <map type="binfile" enabled="yes" data="/home/pi/.navit/new_map.bin"/> </mapset>
Setup the GPS receiver 1. For USB devices. After plugging the device into the usb port type dmesg and you should see somewhere that a new device was mapped on /dev/tty... Most probably the file name would be /dev/ttyACM0. 2. For Serial(UART) modules. The device will have the file name as /dev/ttyAMA0. You can test that the device is connected to a file name by calling cat/dev/ttyAMA0, for example and you should see some NMEA output. Now, copy this file name and put it in the file /home/pi/StartCarPC in the section: # Start gpsd # /dev/ttyAMA0 - RPI serial port # /dev/ttyACM0 - usb port sudo killall gpsd gpsd /dev/ttyAMA0
Voice configuration for Navit Each time a road indication has to be made, Navit will execute the file /home/pi/.navit/speech.sh with the indication text. This file will play a sound and the speak the indication, through speakers. aplay -r 44100 /home/pi/.navit/notification3.wav & sleep 0.7 && espeak -ven+f4 -s150 -a 150 -p 50 "$1" --stdout | aplay /home/pi/.navit/notification3.wav - the sound that will be played each time before an indication -ven+f4 - female voice number 4 -s150 - speed 150 words per minute -a150 - amplitude -p50 - pitch You can find more settings in the espeak manual If you don't want the voice guidance you can press the speaker button in Navit and it will be turned off.
Configure the Controller The controller can be easily used with Steering wheel controls or other physical controls in your car. To enable this controller, you have to edit the file /home/pi/StartCarPC and search for the entry: # Start the GPIO Remote #sudo opencarpc-controller /home/pi/gpio_description & You have to change it to: # Start the GPIO Remote sudo opencarpc-controller /home/pi/gpio_description & Now, you can set the configuration file like in this post
Change the car logo in the Home screen If you want to put another car logo you have to edit the file /home/pi/.xmc/addons/skin.CarPC-touch/16x9/Home.xml and find the entry: <posx>580</posx> <posy>205</posy> <width>550</width> <height>550</height> <texture>bmw_logo.png</texture> Here, you can set your new image instead of bmw_logo.png you can put a complete path of the new image.
Set up a WIFI connection If you want to have internet connection, or airplay or control the whole system using the XBMC remotes, you have to setup a wifi hotspot with your phone and then use an USB WIFI dongle(I am using EDIMAX EW-7811UN dongle). The system is configured to automatically connect to a wifi hotspot with the following settings: wpa-ssid "opencarpc" wpa-psk "opencarpc123" You can find these settings in the file /etc/network/interfaces.
I have worked on some new features for my CarPC. Here are the changes: First, some videos:
The latest image can be downloaded from the Downloads link on the right of this blog(username:pi, password:a). Note! If you do not have any rotary encoder connected or any buttons with a resistor you need to disable the carpc-controller application. You can do this by editing the file /home/pi/StartCarPC and commenting the line which contains carpc-controller.
Hardware updates: - added ViewHd HDMI to HDMI+audio board - added SI4703 FM Radio module - created an expansion board with fm radio module and three connectors(one for GPS receiver and two for rotary encoders) - added a very cheap board to mix two output channels(RPI and radio) into a single output(which goes to the amplifier, in my case AUX input of the car player)
Software updates: - added loading movie(created by Doru Ignat) - added a python server responsible for controlling the radio module via i2c - added new XBMC plugin for controlling the FM Radio(including storing up to 5 radio stations in a file) - improved carpc-controller to support sending multiple commands for a single button press or encoder turn(e.g. turning right one rotary encoder can increase the volume in XBMC and the volume of radio at the same time) - improved the speed in Navit clicking - improved the Navit OSD for both day and night setup(Navit switches automatically teh setup based on the time of the system). - added time synchronization mechanism based on GPS readings(RPI does not have a real time clock)
The expansion board.
RE1 and RE2 are rotary encoders.
The FM Radio driver and Python server. The FM Radio module is connected using i2c communication interface(GPIO0-SDA and GPIO1-SCL of the PI). The radio driver is contained in the si4703 python class. The Radio server is implemented in the file radio_server.py(which is automatically started at boot time). This server simply opens a socket and waits for data. After any data is received, a couple of if-else statements different radio functions are called base on the incoming data. The available commands are:
seek_right - search for a new station in the right of the current frequency seek_left - search for a new station in the left of the current frequency tune_xx.x - set the current frequency to xx.x MHz volume_xx - set the volume of the radio module to xx. xx should be between 0 and 15 toggle_mute - toggle mute get_frequency - get the current frequency
The server reply with the current frequency for each command.
Simple test. To understand how this radio server-client works you can make the folowing experiment: 1. Plug the gpio expansion board(or wire the radio module to the PI as in the above schematic) 2. [Server] Connect using one ssh window(I use Putty) to the PI and enter the folowing commands: cd radio sudo python radio_server.py The radio server should initialize the radio module and start the server. 3. [Client] go to the radio folder and use radio_client.py to send commands o the radio server, like in the folowing picture:
The file radio_client.py simply opens an UDP socket, puts an '_' character between arguments and send the obtained string to the server socket.
The radioFM XBMC plugin. In order to simplify user interaction I have created a new XBMC plugin(radioFM). Its purpose is to allow interacting with the Radio Server(and with the Radio Module) using the touch screen. In order to be able to use this plugin you need to have the radio_server.py started and the FM module plugged in.
Features:
The current frequency is displayed at the top.
The left and right arrow buttons are for seeking to the next channel(left or right).
The bottom 5 buttons are preset channels(these are kept in a file so they are available after reboot).
The Set/Tune Channels button is used for changing the mode in which the bottom buttons are operating. By default they are in the 'Tune' mode, so if you presss them the radio will tune to that frequency. If you press the Set/Tune Channels button once you will enter the Set mode, which will allow you to store the current channel in which preset button you like(or in all of them... if you want) by pressing it once. You will see that the frequency will be changed.
Connecting two audio sources(RPI and Radio) to one amplifier. In order to correctly hook up two audio sources together(putting them in parallel) for a single output you have to use one schematic from this document. I have used the last schematic. Don't forget to use at least 1% tolerance for the resistors. The new GPIO controller. The GPIO controller is now using the official XBMC client code from xbmcclient.h. Now, you can call a lot more XBMC functions for any button pressed or encoder movement.
TODO List: - update to the latest Raspberry PI firmware(today it is possible but then Navit won't be visible) - remove the calibration file for XBMC(/usr/share/eGalax/touchscreen_axes_calib) and use the values from the Debian calibration file(/usr/share/X11/xorg.conf.d/01-input.conf) - create an XBMC addon to allow calibrating the touch screen for both XBMC and X11 windows and also for calibrating the external encoders and button - create a configuration page(XBMC addon) for the carpc-controller settings - create a better audio mixer unit - create a new page for launching different X11 applications
This is an update for my CarPC project. You can download the latest image from the link on the top right corner of this blog(username:'pi', password:'a'). The main features are: Hardware:
[Media Center] - omxplayer - XBMC 12.2 Frodo - media formats supported: listed here - sources with objects build on 27.July.2013 - skin: CarPC-touch(download current version) - system shutdown button(safely stop xbmc and safely halt) - reload skin button - switch to camera view button - modified spectrum analyzer(OpenGL with no rotation) - eGalax touch screen calibrated - eGalax touch screen click&drag fix - black rectangle behind XBMC removed - patch to add getMousePosition feature to xbmcgui module(used to redirect clicks from the Navigation skin page to X11 using xdotool)
[Navigation] - Navit build from source - Zoom In, Zoom Out buttons - Click sent from XBMC to X11 (Navit Window)
GPS Setup 1. Connect GPS module to UART TX, UART RX, GND and 3.3V or on a usb port. 2. If you are using an UART GPS module, as I did, use this tutorial or any other to setup UART communication. 3. Connect GPS to gpsd: sudo apt-get install gpsd gpsd /dev/ttyAMA0 Adding maps to Navit In order to add new maps to Navit, there is a simple process. First, go to Navit Planet Extractor and download your desired area file(this will be a .bin file). After this, transfer the file to your Raspberry PI in the folder /home/pi/navit_export/build/navit/maps/. Here, you should also update the existing .xml file and add another entry for your new map. My .xml file is looking like this:
Safety: - The wires are 2mm in diameter with good insulation, resistant at temperature variations - I have added fuses(1.5A for the radio, 1A for Raspberry PI, 1A for display, 0.1A for reverse camera trigger, 0.1A for reverse camera video signal)
Bugs: - sound pops(will soon disappear by using this hdmi to hdmi and audio splitter) - Navigation is behind Video Player -> Navigation isn't visible while playing videos(this isn't a big issue)
