Installing Video/Audio device

Installing Video/Audio device

The chosen device is a Nanopi M4 from FriendlyElec.

Estimated hardware costs:

Per device: $ 80.97, including:

• Board;
• Power adapter and cable;
• Heat sink;
• EMMC module (16GB);
• American/European adapter.

Plus, shipping costs ($ 11.00).

In the case of fast and secure shipping with DHL (recommended), an average of $ 5.00, plus the VAT on the entire costs will be added.

Total cost: € 85 (plus VAT) per piece.

Installation

Download the 'Official-ROMs-eMMC-20190718.7z' file from the FriendlyArm Google repository (about 16GB).

Then, extract the 'rk3399-eflasher-friendlydesktop-bionic-4.4-arm64-20190718.img' file and flash it through balenaEtcher to a (minimum 16GB) SD card.

Insert both the eMMC module and the SD card on the NanoPI M4 device, and power on it. Connect a monitor and a keyboard/mouse to the device, and flash the eMMC module. Then remove the SD card and restart it.

Software

Connect via SSH, and install the required modules.

apt-get update
apt-get install x11vnc
apt-get install vlc
apt-get install clementine
apt-get install shotwell
apt-get install libreoffice
apt-get install smbclient
apt-get install dos2unix

Maybe vlc should be started with the command:

vlc --vout x11

Configuration

Then configure the board:

npi-config

Set:

• timezone;
• language;
• name of the device;
• audio device.

From the GUI, configure the audio via the left-top corner icon. Both the devices listed should be set to 'analog audio' and set to active.

Transfer your background (1920x1080) and, with right-click on the desktop, select desktop preferences and set the background image.

Icons:

• From a terminal, go to '/home/pi/desktop' and move the unneeded files;
• from the left-top menu, select the needed icons and right-click, then select 'add to desktop'.

VNC

Command to run x11vnc:

x11vnc -auth /var/run/lightdm/root/:0 -loop

Remote and local storage

Create a local link to the desktop for the (optional) local storage:

ln -s /local /home/pi/Desktop/localstorage

/xxxx is the path of the local storage, maybe this should be mounted with the usual command

mkdir /local
mount /dev/xyz /local

Create a remote link to the desktop for the remote storage:

mkdir /remote
mount -t cifs //<IP>/<DIR> /remote -o username=<X>,password=<Y>,vers=2.0
ln -s /remote /home/pi/Desktop/remotestorage

Use this script

#!/bin/sh

POINT=`cat /root/eywa/storage.cfg | grep POINT | sed -e s/POINT=//`
MOUNT=`cat /root/eywa/storage.cfg | grep MOUNT | sed -e s/MOUNT=//`
USER=`cat /root/eywa/storage.cfg | grep USER | sed -e s/USER=//`
PASSWORD=`cat /root/eywa/storage.cfg | grep PASSWORD | sed -e s/PASSWORD=//`
MOUNTED=`df ${POINT} --output=target | tail -1`

if [ "x${MOUNT}x" != "xx" -a "x${MOUNTED}x" != "x${POINT}x" ]
then
    echo "Not mounted, mounting..."
    if [ "x${USER}x" = "xx" ]
    then
        mount -t cifs ${MOUNT} ${POINT}
    else
        mount -t cifs ${MOUNT} -o username=${USER},password=${PASSWORD} ${POINT}
    fi
    sleep 1
    NEWMOUNTED=`df | grep ${POINT} | wc -l`
    echo "Newmounted = ${NEWMOUNTED}"
    if [ ${NEWMOUNTED} = 1 ]
    then
        echo "Killing processes for logging"
        killall node
        killall CaptureImage1
    fi
fi

and this configuration file

POINT=/mnt
MOUNT=//10.10.10.151/xxx
USER=fabio
PASSWORD=xxxxxxx

to mount shared folder at boot, the /etc/crontab line should look like this

* * * * * root /root/mountstorage.sh

Then go to /home/pi/Desktop and execute

ln -s /mnt share

Start at boot

Create the file /etc/systemd/system/x11vnc.service:

[Unit]
Description="x11vnc"
Requires=display-manager.service
After=display-manager.service

[Service]
ExecStart=/usr/bin/x11vnc -xkb -noxrecord -noxfixes -noxdamage -display :0 -auth guess -rfbauth /etc/x11vnc.pass
ExecStop=/usr/bin/killall x11vnc
Restart=on-failure
Restart-sec=2

[Install]
WantedBy=multi-user.target

Then, enable it:

systemctl enable x11vnc.service

Disable screen

Go to the menu, and then to Preferences - Light Locker settings. Disable it.

You should create a script that executes this command:

xset dpms force off

If the monitor is seeking for a signal, maybe it will we reactivated in seconds. So, maybe you have to do a script that repeats the same command every second until the monitor gives up searching.

In order to prevent to accidentally log-out (and make it impossible to reconnect again), edit the file

/home/pi/.config/lxpanel/LXDE/panels/panel

and comment the last stanza:

#Plugin {
#  type=launchbar
#  Config {
#    Button {
#      id=lxde-screenlock.desktop
#    }
#    Button {
#      id=lxde-logout.desktop
#    }
#  }
#}

Create the script disable.sh

#!/bin/sh

END=30

for i in $(seq 1 ${END})
do
  xset dpms force off
  sleep 1
  echo "."
done

and create a symbolic link in the Desktop

ln -s /root/disable.sh /home/pi/Desktop/disable.desktop