The website of Xenomai says the following about it Xenomai:

Xenomai brings POSIX and traditional RTOS APIs for porting time-critical applications to Linux-based platforms. When the native Linux kernel cannot meet the response time requirements of the application, Xenomai supplements it with Cobalt, a small real-time infrastructure which schedules time-critical activities independently from the main kernel logic.

Checking the list of supported hardware, the Raspberry Pi 2, 3 B(+) ARM micro (BCM2835) is included.

This tutorial is almost the same as the tutorial for Preempt-RT patching, but in this case, we need to patch the kernel. The patched Preempt-RT sources are included in the official Raspberry Pi repository. If you need a tutorial for patching the kernel click on the link above.

The Preempt-RT tutorial article is the most visited post on my blog. Therefore, I decided to update the tutorial to make it cleaner, and to introduce some other possible modifications and tips for solving problems.

Preempt-RT is a popular patch for the Linux kernel to transform Linux into such a real-time operating system. There is another option to get this done, and that's Xenomai (tutorial and performance tests here).

Tiejun Chen, the main responsible for the official Raspberry-Pi-RT branch, has published a video about Preempt-RT here. It includes tips, results and tests.

This article extends the node tree of ProjectDiva to include an Arduino Pro Mini.

This article explains how to connect a Arduino Pro Mini to the nRF24Things application (Android Things). The code allows sending and receiving messages between the nodes. It uses the well-known RF24 libraries to create a sensor mesh, where the node 0 (in this case a Raspberry Pi running the Android Things application) actuates as a "DHCP" server and assigns the node addresses in the mesh.

Unboxing Google AIY Vision Kit picked up at Target Manhattan Herald Square -New York!- (Target.com) . Also for the fans of Google AIY Voice Kit keep watching! If anyone made the same experience, please advise!

@Target: It will be great to hear from you!
@Google: Congratulations on your choice of business partner!

If you are going to buy something in this shop, please double check the package and the contain before you leave the shop!

Update 9.07.2018: I managed to get the money back after a 45-minute chat session.

To continue the series of posts "connecting sensors to MicroPython", this article is about the MPU6055 (you can use also the MPU9255, I am still waiting for the Chinese sensor package) and the WiPy 3.0. Combining the IMU sensor with the WiPy and two micro servos 9g, it is possible to stabilize a camera (tilt/rotate).

To calculate the compensation needed for the stabilisation, I added the umatrix, quaternion and ulinalg libraries to the project to make matrix multiplication and quaternion to Euler conversion. The ahrs library from Madgwick fusions the data of the accelerometer, gyroscope (and magnetometer, only with MPU9255) and allows to calculate the rotation of the IMU in quaternion coordinates. I rewrote (most of) the libraries to be compatible with MicroPython.

I got you! Please stop trying to hack my website! It's just a small blog! You are ruining my stats! ;)

Sorry to the other users!, but the last two weeks, someone was using the cloud system ofOnline SAS to try to hack my website. Yes, you heard that right! Someone is trying to hack this small blog! and I can tell you: That's illegal! ;) In the terms and conditions of Online SAS that is NOT allowed! ;P

Are Paris IP-addresses going to be the next Nigeria IP-addresses? abuseipdb.com has a lot of Paris IP-addresses declared as risky!

Leave a comment, if you have more info, and if you are the guy trying to hack my website, please STOP!!!

Thanks Sal for your comments on the article TI: Sensortag CC2650 . This is for you and those who are playing with TI SensorTag!

I've updated the repository of the Texas Instrument (TI) SensorTag CC2650. The repository can be found here . As you may know TI doesn't update the repository anymore. The original last open source repository of the application can be found here .

I've wrote an article last year as I migrated and updated the repository:

• TI: SensorTag CC2650

Today, I've updated the repository to support Android 8.1 (>6.0). The main modification was that Android >6.0 needs location permission for BLE to work. It was first reported as a bug but Google closed the report with status: Won't Fix (Intended Behavior):

To access the hardware identifiers of nearby external devices via Bluetooth and Wi-Fi scans, 
your app must now have the ACCESS_FINE_LOCATION or ACCESS_COARSE_LOCATION permissions

One of the most visited articles on my blog is the Getting started with MicroPython! tutorial. If you still don't know what is MicroPython and you want to start programming microcontroller boards (ESP32, ESP8266 etc.) using a small version of Python 3, you should look at that article. Don't expect to use machine learning or/and other big libraries (the available RAM and microcontroller performance is far away for that aim), but you can do some projects like these:

• Micropython: Merry Xmas & Happy New Year!
• White Hacking: Wemos & Captive Portal using MicroPython
• MicroPython: Geolocation using WLAN
• MicroPython: WeMos and Amazon Echo (Alexa) - Switching LED Colors!
• MicroPython: Vu meter using WS2812B and SPW2430
• MicroPython: Weather Report using NEO-M8N
• MicroPython: Christmas lights!

Google has released Android Things 1.0 this week to developers with long-term support for production devices.

I've updated today the two applications to run on this Android Things version:

• nRF24Things - Related post: here
• SensorTag-Things - Related post: here

Additional resources

Take a look at the full release notes for Android Things 1.0, and head over to the Android Things Console to begin validating your devices for production with the 1.0 system image. If you are looking for a Getting Started on Android Things, head over to these posts:

• #ProjectDIVA: Android Things 0.8.1 getting started!
• #Tutorial: Getting started with Android Things

Docker is a technology that emerged for about 5 years and since then it has simplified the packaging, distribution, installation and execution of (complex) applications. Usually applications consist of many components that need to be installed and configured. Installing all needed dependencies and configuring them correctly is usually time consuming and frustrating for normal users and developers. Here is where Docker comes to simplify this process allowing developers and users to package these applications into containers.

A container image is lightweight, stand-alone, executable packages of a piece of software that includes everything needed to run it: code, runtime, system tools, system libraries, settings. Let me say something before I continue: Docker is not only for application developers, if you are a "normal" user you are going to love it too.

All data needed or used in this tutorial is located on GitHub.

Docker is a technology that emerges for about 5 years and simplifies the packaging, distribution, installation and execution of (complex) applications. Portainer is a management UI which allows you to easily manage your different Docker environments. If you are here because of the post title, I do not have to explain anymore about the Docker technology and the management tool Portainer. But, if you need to know more about these two topics, I leave you two links:

• Docker
• Portainer

Let's start with the installation of Portainer for Docker management on Windows 10.

After the Hannover Fair 2018, I have this weekend some time and I decided to update the #ProjectDIVA to the last version of Android Things. Today the actual version is 0.8.1 DP and the Android Things Setup Utility has the version number 1.0.19.

I have two applications running on Android Things:

• nRF24Things - Related post: here
• SensorTag-Things - Related post: here

In Oct. 2017, I wrote a tutorial for Android Things, but I checked that the tutorial needed an update, and the repositories too. That's why I'm writing this post.

I have a Nexus 5X or I had a working Nexus 5X, and last week it turned black and has finally bootlooped! I bought it from Google Store, so I decided to contact Google. I knew that the warranty was expired on Dec. 2017 (Google repeated it), but this is a common problem of the Nexus 5X, so I thought that maybe I have a chance! But NO! The support was nice, but the solution was to contact LG. A death path! Meaning: No goodwill from Google! Nothing! I contacted LG, and the solution was to send the phone to this address:

DUX Logistics & Tech Services GmbH, Neben dem Mühlweg 20, 65474 Bischofsheim

which doesn't have nice reviews (search the company name on google and you'll see).

I am really happy to inform you that I will be at the Hannover Fair 2018. The Institute of Mechatronic Systems will be represented by our research group "Integrated Systems and Machine Learning" in the Hall 2 on Stand B08 and we will be presenting solutions for the advancing digitization of industrial production.

The Hannover Fair 2018 takes place between Apr 23, 2018 and Apr 27, 2018 in Hannover.

For more info, click here:

You find the map below:

I am writing this post as a tutorial or a 'keep' note for myself, but I think it could be interesting for a lot of people. At work I'm using a Latitude Dell Laptop with dual boot (Ubuntu 16.04 LTS and Windows 10). The laptop has a SD card reader. Usually I work under Ubuntu while I am programming, and the SD card reader support is broken! But typing the following on a terminal, makes it works again:

sudo rmmod sdhci_pci sdhci_acpi sdhci
sudo modprobe sdhci debug_quirks2="0x10000"
sudo modprobe sdhci_pci sdhci_acpi sdhci

It seems to be a problem since Linux kernel version 4.1.8. A bug report here confirms it, with the possible workaround here.

To make this workaround permanent, you need to create a .conf file with the debug_quirks option in the folder /etc/modprobe.d/. Executing the following command on a terminal creates the needed file:

sudo sh -c 'echo options sdhci debug_quirks=0x10000 >> /etc/modprobe.d/sdhci-pci.conf'

Update: if it doesn't work with that, try with this value. It should be slower, but it works:

sudo modprobe sdhci debug_quirks2="0x4"