In-Car (Renault Espace) Raspberry PI - XBMC Media Center with Wifi hotspot

My car is a Renault Espace with integrated screens at the back of the headrests (infrared transmitter for the sound to headsets) with a DVD Player and an extra RCA audio/video input.

Since I was bored with kids battles choosing cartoons from old DVDs I decided to use a Raspberry Pi together with Raspbmc as a media center. Everything had to be powered from the cigar lighter receptacle...

I took an old 2.5" hard-drive as the repository for cartoons. Because of power constraints, I bought a 2.1A dual USB car adapter: it provides enough power for the Raspberry Pi and for the hard-drive; one USB cable goes to the power input of the Raspberry and another "Y" USB cable is connected to the USB car adapter, to the Rabspberry Pi USB port and to the hard-drive. Y USB Cable like this one:http://www.lacie.com/lu/products/product.htm?id=10572.

I wanted to use my iPad as a remote control for XBMC so the idea was to have a wifi emitter in the Raspberry Pi, to connect the iPad to this Wifi network and to use the official remote control app. 

So I bought a cheap USB Wifi dongle: D-Link DWA-121 (less than 13€ on Amazon.fr). This dongle has a Realtek RTL8188CUS chipset compatible with the rtl8192cu linux driver already installed on the latest Raspbmc. However, configuring this dongle as a Wifi access point can turn to be a nightmare! So this post is to help people doing the same thing!

Here is how to proceed, using your home network first before going into the car.

1. Install Raspbmc (http://www.raspbmc.com/download/) on the SD Card.

2. Start your Raspberry Pi and let it boot with a connection to your Ethernet network first. 

3. Use the official XBMC iPad or iPhone app to automatically detect your Raspberry (your iPhone has to be connected to your home Wifi wich uses the same network as the Raspberry Pi).

4. Check the IP address of the Raspberry in the 'Systems' / 'Info' menu.

5. From your PC or your MAC, connect to the Raspberry Pi using an SSH terminal (from MacOS, you can go to a terminal and type

CODE: 

ssh -l pi IP_ADDRESS

where IP_ADDRESS is the one you just checked (for example 192.168.1.11). The password is raspberry. Type

CODE: 

sudo -s

to make sure you have sufficient rights on the device.

6. You will need to follow this tutorial: http://elinux.org/RPI-Wireless-Hotspot but at the first step you have to change the following code:

CODE: 

sudo apt-get install hostapd udhcpd

by this new code:

CODE: 

sudo apt-get install hostapd udhcpd iptables

7. Later in the tutorial you also need to modify the driver from the file /etc/hostapd/hostapd.conf which is

CODE: 

driver=nl80211

by this driver instead:

CODE: SELECT ALL

driver=rtl871xdrv

8. The hostapd file also need to be changed before running hostapd. Download the correct version by typing

CODE: 

wget http://dl.dropbox.com/u/1663660/hostapd/hostapd

then move it to the right place by typing

CODE: 

mv hostapd /usr/sbin

and modify the rights by typing

CODE: 

chmod 755 /usr/sbin/hostapd

9. You should have finished the tutorial by now but there is an ultimate modification to be done. I realized that the Wifi interface was not starting, causing the wifi Access Point not to be working... So you have to modify the /etc/rc.local file by typing

CODE: 

nano /etc/rc.local

and adding the following 2 lines before the exit 0 line:

CODE: 

ifup wlan0
service udhcpd restart

10. Restart you Raspberry Pi, check the Wifi from your iPad: you should be able to connect to your newly create access point, to detect your Raspberry Pi from the official xbmc app and to enjoy an autonomous Wifi Raspberry Pi!


Pictures from the installation in my car:

Official XBMC iPad app together with Raspbmc in my Renault Espace: 

IMPORTANT NOTE:
If you see the SSID  but are not able to connect to it that means that it is probably a DHCP issue: your raspberry is not providing an IP address to your iPad. To solve this, we will simply change the DHCP server...

First thing to check: if you type 'ifconfig', do you have an IP address for WLAN0 interface? If yes, it is really a DHCP issue.

I also had a DHCP issue once and I changed the DHCP server (after a reinstall from scratch). You can do so by typing:

CODE:

apt-get install isc-dhcp-server

to replace the udhcpd server. So you have to stop udhcpd by typing

CODE:

service udhcpd stop

Once the udhcpd is stopped and isc-dhcp-server installed, there is a bit of config to be done. You need to change the eth0 line to have wlan0 in the config file:

CODE:

sudo nano /etc/default/isc-dhcp-server

And then edit the dhcpd.conf file:

CODE:

sudo nano /etc/dhcp/dhcpd.conf

In this file you need to have this type of config (make sure also than eth0 is replaced by wlan0 in this file):

CODE:

option subnet-mask 255.255.255.0;
option broadcast-address 192.168.42.255;
option domain-name "home";
option routers 192.168.42.1; #default gateway

subnet 192.168.42.0 netmask 255.255.255.0 {
    option routers 192.168.42.1;
    range 192.168.42.10 192.168.42.20; #IP range to offer
    option domain-name-servers 8.8.8.8, 8.8.4.4;
}

Finally you need to start the dhcp-server:

CODE:

sudo isc-dhcp-server start

In case of issues, there is a syslog file which gives more details on what fails:

CODE:

cat /var/log/syslog

If it works, replace dhcpd in the rc.local file by isc-dhcp-server so that it starts all the time on boot.

You're done! Enjoy!