\section{Installation}
\subsection{SD card preparation}
\subsubsection{Partitions}
Format the SD card with two new partitions:
\lstsetbash
\begin{lstlisting}
fdisk /dev/mmcblk0
\end{lstlisting}
\begin{enumerate}
\item Type \textbf{o} to erase all former partitions
\item Type \textbf{p} to list all existing partitions
\item Type \textbf{n}, then \textbf{p} to create the boot partition. Press
\textbf{RETURN} to accept the first sector, then \textbf{+100M} for the
last sector
\item Type \textbf{t}, then \textbf{c} to set the partition type to FAT32
\item Type \textbf{n}, then \textbf{p} to create the root partition. Press
\textbf{RETURN} to accept the first sector, then \textbf{RETURN} for the
last sector
\item Type \textbf{w} to write the new partition table
\end{enumerate}

\subsubsection{File systems}
Create the file systems for the new partitions:
\begin{lstlisting}
mkfs.vfat /dev/mmcblk0p1
mkfs.ext4 /dev/mmcblk0p2
\end{lstlisting}
Create mount points and mount the new partitions:
\begin{lstlisting}
mkdir boot
mkdir root
mount /dev/mmcblk0p1 boot
mount /dev/mmcblk0p2 root
\end{lstlisting}

\subsubsection{Download and extract root file system}
\begin{lstlisting}
wget http://archlinuxarm.org/os/\
ArchLinuxARM-rpi-2-latest.tar.gz
bsdtar -xpf ArchLinuxARM-rpi-2-latest.tar.gz -C root
sync
mv root/boot/* boot
\end{lstlisting}
Enable ssh root login:
\begin{lstlisting}
vim root/etc/ssh/sshd\_config
\end{lstlisting}
Find \texttt{\#PermitRootLogin yes} and uncommend it
\begin{lstlisting}
PermitRootLogin yes
\end{lstlisting}
Unmount both partitions
\begin{lstlisting}
umount boot root
\end{lstlisting}

\section{Configuration}
\subsection{User management}
\subsubsection{Create new user}
\begin{lstlisting}
useradd -m -g users -G wheel -s /bin/bash tkl
\end{lstlisting}
\begin{tabular}{ l l }
\texttt{-m} & create user name home directory\\
\texttt{-g} & initial login group\\
\texttt{-G} & list of supplementary groups - comma separated\\
\texttt{-s} & path and file name of default login shell\\
\end{tabular}\\
Set password for the new user:
\begin{lstlisting}
passwd tkl
\end{lstlisting}
Enable wheel group members as sudoers:
\begin{lstlisting}
EDITOR=vim visudo
\end{lstlisting}
Uncomment:
\begin{lstlisting}
%wheel		ALL=(ALL) ALL
\end{lstlisting}

\subsection{Aliasing}
\begin{lstlisting}
cd ~
vi .bashrc
\end{lstlisting}
Add:\\
\texttt{alias vi='vim'}

\subsection{Customize vim}
Edit \texttt{.vimrc}:
\begin{lstlisting}
syntax on	"Syntax highlightning
set number	"Line numbering
\end{lstlisting}

\subsection{Wifi}
Configure wifi network:
\begin{lstlisting}
wifi-menu
\end{lstlisting}
Enable wifi network permanent:
\begin{lstlisting}
netctl enable wlan0-<network_name>
\end{lstlisting}
\subsubsection{Deactivate wifi device sleep mode}
\begin{lstlisting}
pacman -S iw
echo ACTION=="add", SUBSYSTEM=="net", KERNEL=="wlan*", \
RUN+="/usr/bin/iw dev \%k set power\_save off\" \
> etc/udev/rules.d/70-wifi-powersave.rules
\end{lstlisting}

\subsection{Ssh key login}
\begin{itemize}
\item Create \texttt{.ssh/} folder in users home directory
\item Copy public key file (i.e. \texttt{id\_rsa.pub}) into \texttt{.ssh}
folder
\item Authorize public key:
\begin{lstlisting}
cat id_rsa.pub >> authorized_keys
\end{lstlisting}
\end{itemize}

\subsection{Interfaces}
\subsubsection{I2C}
To enable i2c interface edit \texttt{/boot/config.txt}. \\
Uncomment \texttt{\#device\_tree\_param=i2c\_arm=on}\\
Load i2c modules while boot:
\begin{lstlisting}
/etc/modules-load.d/raspberry.conf

i2c-dev
i2c-bcm2708
\end{lstlisting}
Install package \texttt{i2c-tools}
Test i2c bus after reboot:
\begin{lstlisting}
i2cdetect -y 1
\end{lstlisting}
Set permissions for i2c device access:
\begin{lstlisting}
/etc/udev/rules.d/99-i2c.rules

KERNEL=="i2c-1", MODE="0777"
\end{lstlisting}

\subsubsection{SPI}
To enable spi interface edit \texttt{/boot/config.txt}. \\
Uncomment \texttt{\#device\_tree\_param=spi=on}

\subsubsection{GPIO}
Create an udev rule to enable others than root accessing the gpio files:
\begin{lstlisting}
/etc/udev/rules.d/98-gpio.rules

SUBSYSTEM=="gpio*", PROGRAM="/bin/sh -c 'chown -R root:gpio\
/sys/class/gpio; chmod -R 0777 /sys/class/gpio; chown -R \
root:gpio /sys/devices/virtual/gpio; chmod -R 0777 \
/sys/devices/virtual/gpio'"
\end{lstlisting}

\subsection{tools}
\begin{itemize}
\item \texttt{fakeroot}
\item \texttt{gcc}
\item \texttt{git}
\item \texttt{make}
\item \texttt{patch}
\item \texttt{python2, python2-pip}
\item \texttt{wget}
\end{itemize}
\subsection{Hostname}
\begin{lstlisting}
echo "hostname" > /etc/hostname
\end{lstlisting}

\section{Applications}
\subsection{I2C-OLED}
\subsubsection{Oled Test application}
Clone test application:
\begin{lstlisting}
git clone git@dabgit01.internal.novero.com:raspberry/\
oledpi.git
\end{lstlisting}
\subsubsection{Install driver}
Clone oled driver:
\begin{lstlisting}
git clone https://github.com/rm-hull/ssd1306.git
\end{lstlisting}
Install it:
\begin{lstlisting}
python2 setup.py install
\end{lstlisting}
\subsubsection{Dependencies}
\begin{itemize}
\item \texttt{python-smbus/python2-smbus} (AUR)
\item \texttt{i2c-tool-git} (AUR)
\item \texttt{libjpeg-turbo}
\item \texttt{pillow} install using pip \texttt{(pip/pip2 install pillow)}
\end{itemize}

\subsection{Weatherpi}
\subsubsection{Usb weatherstation test application}
Clone test application:
\begin{lstlisting}
git clone git@dabgit01.internal.novero.com:raspberry/\
weatherpi.git
\end{lstlisting}

\subsubsection{Dependencies}
\begin{itemize}
\item \texttt{python2-pyusb} (AUR) (edit \texttt{PKGBUILD} and add
\texttt{'armv7h'} to \texttt{arch})
\item \texttt{libusb-compat}
\end{itemize}

\subsection{MQTT Broker}
Install mosquitto (AUR)\\
Install paho-mqtt client library:\\
\begin{lstlisting}
pip2 install paho-mqtt
\end{lstlisting}
Create config file:
\begin{lstlisting}
cp /etc/mosquitto/mosquitto.conf.example \
/etc/mosquitto/mosquitto.conf
\end{lstlisting}
Start mosquitto broker service:
\begin{lstlisting}
systemctl enable mosquitto.service
systemctl start mosquitto.service
\end{lstlisting}
\subsubsection{Test}
Subscribe to a topic:
\begin{lstlisting}
mosquitto_sub -t "topic/path"
\end{lstlisting}
Populate a message:
\begin{lstlisting}
mosquitto_pub -t "topic/path" -m "message payload"
\end{lstlisting}