Affolter Engineering

Two years back I wrote a XMPP/Jabber bot named pysysbot. It’s based on the Python Jabberbot framework and just gives you system details as answers. In the past days I started to rewrite some parts especially the handling of the configuration file because the old solution did not work well with systemd and was designed to use the user’s home directory to store the configuration. Right, now the bot is under the control of systemd and the configuration was moved to /etc.

From my point of view it’s time to let pysysbot out. To make future installations easier I submitted a review request.

Inspired by mqtt-svg-dash which was created by Jan-Piet Mens I developed my own simple web interface. I think that the idea with the svg is great if you are working with free form elements or complex layouts like a house. I just wanted a simple web interface that display some values/states. I have no need to control the Arduino (this can be done with Breakout.js if needed in the future).

If you are looking for more advanced stuff then you should checkout homeA.

Git repository: https://github.com/fabaff/mqtt-panel
Video: http://youtu.be/Qb0UJa9kf2g

For the measurement of temperatures in a closed system or of the environment, a lot of sensors can be used with the Arduino. For starters the Dallas DS18X20 sensor is a good choice. Those devices are cheap, easy-to-use, and adding more sensors is simple. The simplicity is archived through the 1-wire technology.

The steps below are needed to get the DS18X20 working with Arduino.

• Installation of the OneWire library
• Installation of the Dallas Temperature Control library
• Open the sample example (Examples -> OneWire -> sample)
• Adjust the connection port to match your Arduino port and upload the sample sketch

Pin layout

Front view (the label is readable)

• Leg 1: GROUND
• Leg 2: DQ
• Leg 3: VDD

Wiring

• Standard wiring for DS18X20
• Parasite power mode wiring for DS18X20

To connect a DS18X20 to the Arduino a 4.7 kOhm resistor is needed. The Fritzing schema below shows the wiring of sensor on a breadboard.

The wiring for the parasite power mode of the DS18B20 differs a little bit from the standard wiring. The main distinction is that only two connections are needed (the third legs can have a connection to GROUND too). The Fritzing schema below shows how to wire the sensor on a breadboard to the Arduino.

The “Remove Bluetooth icon” and the “Remove Volume icon” Gnome Shell extensions will soon be available at the Gnome Shell Extensions Website. Currently the extensions are under review.

After the review the users can choose if they want to install the extensions from the Fedora packages or from the website.

The API changes of the Gnome Shell > 3.0.1 required an update of the extensions. The latest release of the Gnome Shell Bluetooth icon remover extension works with the current version of Gnome Shell.

• Website: http://www.affolter-engineering.ch/index.php?page=remove-bluetooth-icon
• Source: remove-bluetooth-icon-0.2.tar.bz2
• SHA1: remove-bluetooth-icon-0.2.sha1sum
• Git repo: https://gitorious.org/remove-bluetooth-icon
• Fedora Packages: http://koji.fedoraproject.org/koji/packageinfo?packageID=12064

The API changes of the Gnome Shell > 3.0.1 required an update of the extensions. The latest release of the Gnome Shell Volume icon remover extension works with the current version of Gnome Shell.

• Website: http://www.affolter-engineering.ch/index.php?page=remove-volume-icon
• Source: remove-volume-icon-0.3.tar.bz2
• SHA1: remove-volume-icon-0.3.sha1sum
• Git repo: https://gitorious.org/remove-volume-icon
• Fedora Packages: http://koji.fedoraproject.org/koji/packageinfo?packageID=12065

To create an Alpine ISO image with a specific set of packages only a plaintext list of packages and a configuration file is needed. Sometimes you wish to have some additional documentation or description about the included packages available and not only the package list. Here comes config-builder into play. config-builder is able to create a package list from a mediawiki page or the Alpine Linux Git repository. Below are two pages that are included in the config-builder script.

• Alpine Rescue
• Alpine Mini

config-builder allows you to grab data from any mediawiki instance to build your package list. A requirement for the mediawiki pages is that the package names are placed in a table (class wikitable). Beside that nothing else is needed. You are free to format your page as you like. If you are unsure about the table layout just take a look at one of the two page mentioned above.

More details about the creation of Alpine Linux ISO images can be found at this wiki page.

Source code: http://git.alpinelinux.org/cgit/fab/alpine-iso.git/

This Gnome shell extension removes the bluetooth icon from the panel.

Dowload the tarball to $HOME/.local/share/gnome-shell/extensions and unpack it.
A new directory called remove-volume-icon@affolter-engineering.ch should be created.

If you prefer to use the latest source clone the git repository and run
su -c 'make install'

Now restart your Gnome shell (Alt-F2 and ‘r’) and the bluetooth icon should be gone.

• Website: http://www.affolter-engineering.ch/index.php?page=remove-volume-icon
• Source: remove-volume-icon-0.1.tar.bz2
• SHA1: remove-volume-icon-0.1.sha1sum
• Git repo: https://gitorious.org/remove-volume-icon

remove-bluetooth-icon is licensed under GPLv3+, for more details check COPYING.