Thursday, May 4, 2017

Install Money Manager EX in Ubuntu 16 - MMEX


Money Manager EX is a nice tool to keep track of personal finances and expenses. And while installers exist for windows, in Linux one has to compile the software alone. This has proven to be somewhat more difficult than expected, but with the right dependencies and following the guide it is possible.

Compile from git repository and install

Following the Ubuntu guide from Github one needs to do,
  1. Install dependencies
    sudo apt-get update && sudo apt-get upgrade
    sudo apt-get install git build-essential automake libwxbase3.0-dev libwxgtk3.0-dev libwxgtk-webview3.0-dev python-dev build-essential cmake git libgtk-3-dev libwebkitgtk-dev libwxgtk3.0-dev libwxgtk-webview3.0-dev libwxsqlite3-3.0-dev
    (In the github documentation the latter libwsqlite3-3.0-dev is not mentioned, however it is necessary for compiling. Without this I was getting errors while compiling)
  2. Clone the git repository
    git clone --recursive https://github.com/moneymanagerex/moneymanagerex
    (I found that the --recursive parameter is important, otherwise I got some files missing in the end)
  3. For the release (no debugging build) configure and compile as
    cd moneymanagerex/build
    mkdir release
    cd release
    cmake -DCMAKE_BUILD_TYPE=Release ../../
    make package
  4. After this you can install it with
    sudo make install
  5. and finally run from the terminal window with
    mmex
MMEX running under Ubuntu 16

Note: For make you can pass the argument "-j x" where x is the number of threads to use.

Creating a desktop launcher

Create a file called Mmex.desktop (yes, .desktop) on your desktop.
nano ~/Desktop/Mmex.desktop
Paste the following into the file
#!/usr/bin/env xdg-open
[Desktop Entry]
Version=1.0
Type=Application
Terminal=false
Exec=mmex
Name=Mmex
Comment=Money Manager
Icon=/usr/local/share/icons/hicolor/scalable/apps/mmex.svg
Make the file executable with
chmod +x ~/Desktop/Mmex.desktop
You should be left with the following, a nice desktop launcher.
Mmex desktop launcher and the location of the Icon
What is what?
Exec - command that gets executed
Name - The visible name of the file (hence you don't see the .desktop extension)
Comment - Additional comment if you like
Icon - path to the icon to display, otherwise blank launcher image




Monday, May 1, 2017

A job is running for dev-mapper-cryptswap1.device

If you notice that booting Ubuntu takes a long time and you see the following error message on the booting screen after pressing 'ESC',
A job is running for dev-mapper-cryptswap1.device (50s / 1m30s)

This is caused by the system looking for an encrypted swap partition, however most likely you have not created one. Which is normal, now when a lot of RAM is available, and a swap partition is not necessary. This is all due to a misconfiguration entry in the fstab, which tells the system to try and mount the said (non existing) partition.

Solution

The solution is to remove or comment out the "cryptswap" entries from /etc/fstab and /etc/crypttab.

This can be done easily by editing the above mentioned files as commenting out the lines that say cryptswap by placing a "#" in front of the matching lines.
sudo nano /etc/fstab
sudo nano /etc/crypttab
The result is shown below in the image, where the lines referring to the cryptswap partition are already commented out.

Reminder: 'CTRL + O' saves the file, 'CTRL + X' exits the nano text editor.

Both fstab and crypttab have an entry for cryptswap1, shown as already commented out

Tuesday, January 24, 2017

Install Steam Controller on Ubuntu 16.04

I have a Steam controller that I use every now and then and wanted to try it on Ubuntu 16.04. However, the operating system did not recognize the controller automatically, as of 22.01.2017 on a fresh install of Ubuntu 16.04. Luckily, it can be added quickly without any extensive troubleshooting.


Detecting the steam controller in ubuntu
Ubuntu 16.04 detecting the Steam controller for the first time.

Add a Controller

Referring to an earlier post from November 2016 on AskUbuntu.com the solution is quite straightforward and applies to a fresh 16.04 install.

  1. To install the controller we have to add a new device manually with udev,
    sudo gedit /lib/udev/rules.d/99-steam-controller-perms.rules
  2. There is no such file by default, so the above command will create it. Simply copy the following into it,
    # This rule is needed for basic functionality of the controller in Steam and keyboard/mouse emulation
    SUBSYSTEM=="usb", ATTRS{idVendor}=="28de", MODE="0666"

    # This rule is necessary for gamepad emulation; make sure you replace 'GROUP' with a group that the user that runs Steam belongs to
    KERNEL=="uinput", MODE="0660", GROUP="GROUP", OPTIONS+="static_node=uinput"

    # Valve HID devices over USB hidraw
    KERNEL=="hidraw*", ATTRS{idVendor}=="28de", MODE="0666"

    # Valve HID devices over bluetooth hidraw
    KERNEL=="hidraw*", KERNELS=="*28DE:*", MODE="0666"

    # DualShock 4 over USB hidraw
    KERNEL=="hidraw*", ATTRS{idVendor}=="054c", ATTRS{idProduct}=="05c4", MODE="0666"

    # DualShock 4 wireless adapter over USB hidraw
    KERNEL=="hidraw*", ATTRS{idVendor}=="054c", ATTRS{idProduct}=="0ba0", MODE="0666"

    # DualShock 4 Slim over USB hidraw
    KERNEL=="hidraw*", ATTRS{idVendor}=="054c", ATTRS{idProduct}=="09cc", MODE="0666"

    # DualShock 4 over bluetooth hidraw
    KERNEL=="hidraw*", KERNELS=="*054C:05C4*", MODE="0666"

    # DualShock 4 Slim over bluetooth hidraw
    KERNEL=="hidraw*", KERNELS=="*054C:09CC*", MODE="0666"
    Make sure to replace GROUP with the user's group that will run Steam. In most installations your username and group will be username:username, hence your username will suffice. If in doubt, you can check what groups you belong to simply by,
    groups username
  3. Unplug the controller adapter if it was plugged in.
  4. Re-plug the controller adapter. 
That should be it. Enjoy gaming.

Saturday, January 21, 2017

Install Cura 2.x on Ubuntu 16.04

Cura is a slicer software that prepares your 3D drawings for printing. Installing the latest version on Ubuntu 16.04 was not as easy as downloading the .deb file and installing it from the official site at: https://ultimaker.com/en/products/cura-software.


Cura 2.x running under Ubuntu 16.04

Install from repository

Firstly, since Cura depends on python 3.x, let's get the dependencies first,
sudo apt-get install python3 python3-dev python3-sip
Then add the following repository,
sudo add-apt-repository ppa:thopiekar/cura
Finally, update packages list and install cura.
sudo apt-get update && sudo apt-get install cura
After this you should be able to run cura either with the command cura from the terminal or from searching through dash.
Cura
Launch Cura from Ubuntu dash,

Saturday, January 7, 2017

Send email with PHP and crontab on reboot in Ubuntu

Even with the best VPS services reboots can happen: maintenance, hardware upgrade, kernel upgrade. Most of the time users are warned in advance so that they can prepare for the service outage. However, it can happen that there is a reboot and you did not know about it or simply forgot. 

I just added a small php script to my server to send me an email if it was rebooted. This way I can log in ASAP and restart services that do not start automatically.

Send email via PHP

This assumes that you have php installed on your Ubuntu instance.

A simple php program to send emails can look like this:

<?php
$to = "email@address.com";
$subject = "Reboot";
$txt = '

Hello, your server has been rebooted and services have most likely stopped.
If this reboot was unscheduled please log in to restart services.

Have a nice day!
';


// To send HTML mail, the Content-type header must be set
$headers  = 'MIME-Version: 1.0' . "\r\n";
$headers .= 'Content-type: text/html; charset=iso-8859-1' . "\r\n";

//More headers
$headers = "From: server@server.com" . "\r\n" .
"CC: ";

mail($to,$subject,$txt,$headers);
?>

It is kind of self-explanatory, but just to explain quickly: 

to: email address of the recipient
subject: subject of the email
text: main body of the email until the final semicolon (;). Note that you can also send html-based emails. To do this, simply used the html codes such as,
$text = '<html>
<head>
</head>
<body>
This is a html <br> message!
</body>
</html>'
headers: sets the message header. You can write any email address in the "from" field.
mail($to,$subject,$txt,$headers); : sends the email with the previously defined variables above.

Create and test

  1. You can save the above in a .php file. (I prefer to have a MyScripts directory in my /home, just to keep everything organized.)
  2. Test if the program is working.
    sudo -u www-data php -f rebootMail.php
    This will call php, as the user "www-data", and launch the specified file. If your web server's default user is not www-data, adjust accordingly.

Note: If you have a web server running, you can run the above php program from your web browser. Simply copy the rebootMail.php into your /var/www (or wherever your web server's / is) and visit serveraddress.com/rebootMail.php. If you have done everything correctly, you should receive an email. Although, in this case the php program can be executed by anyone visiting it's web address.

Auto-launch program on reboot 

This can be done either via crontab or using /etc/rc.local. Let's do it via crontab.
  1. To edit existing cron scheduled tasks (no sudo needed),
    crontab -e
  2. In a new line at the end of the file add,
    @reboot /usr/bin/php /path/to/rebootMail.php
  3. Save changes and exit the nano editor,
    Ctrl + O
    Ctrl + X
Done. If all done correctly, you should now receive an email on every reboot. To make sure everything is well configured, you should reboot your server manually once and confirm that it works.

Note: If your php is not installed in /usr/bin, adjust the path accordingly.

Sunday, September 11, 2016

Change Banana Pi M3 CPU Frequency

This is a short script for changing the CPU clock rate of the Banana Pi M3 in the allowable steps between 480 MHz to 1.8 GHz.

Motivation

Since the Banana Pi M3 heats quite a bit at 1.8 GHz (even with heat sinks), lowering the CPU frequency can bring these temperatures down. The clock rate can be tuned between 480 MHz and 1.8 GHz by default, possibly up to 2 GHz when the CPU voltages are adjusted and unlocked. 

Note: This script only adjusts the speed up to 1.8 GHz.

How-to

  1. Download the script from Pastebin [Direct Download
  2. Copy it over to your Banana Pi M3
    scp BananaPiM3_FrequencyChanger.sh user@bananapi:/home/remoteuser/
  3. Make it executable
    chmod +x BananaPiM3_FrequencyChanger.sh
  4. Run it with
    ./BananaPiM3_FrequencyChanger.sh

Optional:  Add an alias in your .bash_aliases to call it faster!
echo "alias frequency='./BananaPiM3_FrequencyChanger.sh'" >> .bash_aliases
Apply the changes with,
source .bashrc
From now on you can call the script with
frequency
Screenshot of the script in action.
Screenshot of the script, setting my board's frequency to 1 GHz.

Wednesday, August 31, 2016

Large Heat Sink on Banana Pi M3

So while I was playing with the idea of running BOINC - on my otherwise mostly idle - octa-core Banana Pi M3, I remembered that the previously added tiny heat sink will probably not do much good. The CPU is still easily heating to 65-67 degrees Celsius even with a CPU clock rate set to 1GHz and under moderate load.
Small heat sink installed on my Banana Pi M3
Small heat sink installed on my Banana Pi M3

Sizing

I started looking around in my "random parts box" and found a roughly 5*5 cm aluminium heat sink, with a slight plateau on the bottom, in the centre line where something used to be attached. Unfortunately, there isn't any mounting opportunity on the board and everything is tightly packed. The CPU and the RAM are the same height, but some parts directly next to them are slightly higher and this puts a limit on how large the heat sink can be. I measured and a roughly 3.5*2.5 cm heat sink should give enough clearance from nearby parts. I had to cut my heat sink into pieces, but it worked.
Heat sink cut into 3 parts. 1 scrap and 2 useful sides.
Heat sink cut into 3 parts. Bottom one is scrap, left and right are the right size.

Mounting

I cleaned and polished the cut edges a bit and made sure it fits on the board. I put a grain of thermal paste on both the CPU and RAM and aligned the part carefully. It fits just right and the paste also gives a bit of mechanical stability, although not much. It is not visible on the pictures, but to hold the heat sink in place I have used 2 pea-sized balls of glue on the side of the heat sink close to the GPIO pins. Ideally I would have used a glue gun, but since I do not have one, I used the 2 component Pattex glue paste.

As you can see below, the heat sink has an odd-shape with one "arm" extending over the eMMC storage (to the right), whereas contact is only made on the left side with the CPU and RAM. I realize it is an oddly shaped heat sink, but the shape allowed me to use a surface area as large as possible.

Large heat sink mounted on the Banana Pi M3.

Large heat sink mounted on the Banana Pi M3. Side view.


 It is an odd shape, yes, but it is the added thermal mass and the surface area that matters.

Result

  • I have been running BOINC on 6 cores at 100% load, using a clock frequency of 1GHz for about 45 minutes and the temperature seems to have maxed out at 62-63 degrees Celsius. Ambient temperature of 27 degrees Celsius.
  • The heat sink seems to sit tightly, despite the agreeably dodgy mounting. I wish I could have added some screws, but there simply isn't enough space.
  • The possible drawback is that since the heat sink covers both the RAM and CPU, it is quite likely that it is in fact heating the RAM. I am not sure if this is the case - or to what degree as the RAM was usually hot as well, just checking by touching - nevertheless, I'll keep an eye on this.
I will do a bunch of testing to see what temperatures I get at different CPU speeds and number of cores used. Stay tuned.