#########################
OS installation - Armbian
#########################

Armbian is an operating system for ARM based boards based on Debian. It is the
recommended operating system for MuxPi board.

There is also a flavour of Armbian based on Ubuntu, which should work in a
similar manner to the Debian one, although it is not supported.


************
Installation
************

.. highlight:: console

#. Download the latest Stretch `Armbian for Nanopi Neo`_. You can either use
   `torrent`_ or `http`_ download. We will download via http using wget. You
   can install wget on Debian-based distributions with ``apt-get install
   wget``::

      $ wget https://dl.armbian.com/nanopineo/Debian_stretch_next.7z

   .. _`Armbian for Nanopi Neo`: https://www.armbian.com/nanopi-neo/
   .. _`http`: https://dl.armbian.com/nanopineo/Debian_stretch_next.7z
   .. _`torrent`: https://dl.armbian.com/nanopineo/Debian_stretch_next.7z.torrent

#. Uncompress the downloaded file. It will likely be a ``.7z`` file. To extract
   it we will use `7-Zip`_. You can install it on Debian-based distributions
   with ``apt-get `install p7zip-full``::

      $ 7z e Debian_*

   .. _`7-Zip`: http://www.7-zip.org/

#. Verify if the download and unpacking were successful by checking checksum::

      $ sha256sum Armbian_*.img

   Output should be the same as contents of sha256sum.sha file.

#. Connect your SD card and check which ``/dev/sdX`` it is. You can do this
   using e.g. fdisk::

      # fdisk -l

#. Copy the extracted image to your SD card.

   .. danger:: Make sure your ``/dev/sdX`` device is the SD card. If performed
      incorrectly, next step may destroy your files unrecoverably and even stop
      your machine from working.

   .. note:: You need to adjust Armbian_*.img name as dd tools does not take
      wildcards.


   ::

      # dd bs=1M if=Armbian_*.img of=/dev/sdX

   You can verify if the image was copied correctly by running::

      # sha256sum /dev/sdX

#. Put prepared SD card in your MuxPi's NanoPi SD card slot.


*************
Configuration
*************

#. Connect NanoPi's UART0. You can use the UART->USB converter on the MuxPi
   board, just connect a cable to  microUSB port on the bottom of the board.

   .. note::

      You can omit this if you connect the device to DHCP server and
      connect over ssh. You will need to adjust below steps in such case.

#. Connect to serial using either screen or minicom (or your tool of choice)

   .. warning::

      Change ``ttyUSB0`` to your serial that is connected to NanoPi.  If you do
      not  have any USB UART connected, MuxPi's converter should be
      ``ttyUSB0``.

   ::

      # screen /dev/ttyUSB0 115200

      # minicom -b 115200 -D /dev/ttyUSB0


#. Power the device on. First boot might take some time.

#. After system boots, you need to log in::

      login: root
      password 1234

   .. note ::

      ``1234`` was the correct password at the time of writing this page. If it
      does not work, you should check FAQ section on `Armbian for Nanopi Neo`_
      page.

#. You will be asked to change your password:

   ::

      You are required to change your password immediately (root enforced)
      Changing password for root.
      (current) UNIX password:
      Enter new UNIX password:
      Retype new UNIX password:

#. Next, you will be greeted with nice, colourful text and initial non-root
   user account configuration. Follow the interactive user creation process.

   We always create a ``pi`` user.

#. Set static IP on the device by creating following file::

      # vim /etc/network/interfaces.d/eth0

   With the following contents:

   .. code-block:: none

      auto eth0
      allow-hotplug eth0
      iface eth0 inet static
      	address 192.168.0.2
      	netmask 255.255.255.0
      	gateway 192.168.0.1

   Above will work if you connect MuxPi to your machine (which will have
   192.168.0.1 address) and the 192.168.0.2 address will be available.
   For this document purpose we will assume the IP address is ``192.168.0.2``.

#. Settings need to be changed, you need to restart networking::

      # systemctl restart networking

   Or just restart the whole device::

      # shutdown -r now

#. Now you should be able to connect to device through ssh::

      $ ssh root@192.168.0.2

   .. note::

      If you are not able to connect to it, it might mean that the network
      settings did not reload properly. It is best to restart device using
      serial connection from earlier::

         # shutdown -r now

#. Configure UARTs for communication with MuxPi's stm and for communication
   with DUT::

      # armbian-config

   It will ask you for internet connection but it is not required (press any
   key to continue)

   Go to :menuselection:`System --> Hardware` and enable ``uart1`` and ``uart2``.

   Reboot when asked.

.. target-notes::