This part 2 of the tutorial will allow you to get data from the smart power outlets and send it to the Google Cloud Platform (GCP) throught the Google IoT Core and using an ESP32 programmed with Zerynth (Python). This data is not usually available to the user (directly, you need to use the power outlet application), and it is sent to the company servers.

If you want to check, if your power outlets are compatible for this tutorial, they should have the port 6668 opened. To check that:

>>> nmap <<ip-address>> -p 6668
[...]
Host is up (0.13s latency).

PORT     STATE SERVICE
6668/tcp open  irc

If the answer is as shown above, the port is opened. If you don't have the nmap application and you are on Windows, look at the Nmap Network Scanning tool. On Ubuntu type on a terminal sudo apt-get install nmap.

Today there is a wide range of offer for home automation devices. A lot of sensors, actors etc. can be connected to the cloud and be controlled using Google Home, Amazon Alexa, your smartphone, etc. There are a lot of companies offering low cost devices, e.g. Sonoff, Tuya, Teckin etc. Most of these solutions are based on ESP32 or ESP8266, and all of them send data to cloud solutions usually deployed on Amazon services, and the data is only accessible using the Android/iOS applications. They can be also controlled using voice commands over Google Home or Amazon Alexa devices.

Nice, but... my aim was to control these devices locally (using LAN and not Wi-Fi) and send the data to the Google Cloud Platform (GCP) to make some analytics later. To be clear, when you use the Android/iOS application (or Google Home/Amazon Alexa) and you switch on/off e.g. a smart power outlet, the application connects with the company server in which the smart power outlet is registered and it sends the command. Then, the server sends back the action to your smart outlet. An exception is Amazon Alexa that sometimes connects directly to the devices (e.g. Belkin switches / Philips Hue), when you are at home on the same network (Wi-Fi). That's why you can re-program the Sonoff devices using Sonoff-Tasmota and then, you don't need a cloud connection anymore. However, if you use Google Home, this is not possible.

To sum up the aim of this post: Using this tutorial, you'll be able to control locally (LAN) most of the low-cost smart power outlets using an ESP32 programmed in MicroPython. Additionally, you can use the available data to do some analytics.

Note: Application like home assistant allows you to make this too, but you need at least a Raspberry Pi to run it, and that means power consumption. That's why, I like to do this with an ESP32 and of course, using MicroPython!

LoRa (Long Range) is a patented digital wireless data communication technology. It was developed by Cycleo of Grenoble in France and then acquired by Semtech in 2012. Semtech defines the Lora Technology "as the DNA of IoT, which connects sensors to the Cloud and enables real-time communication of data and analytics that can be utilized to enhance efficiency and productivity".

To sum up, LoRa is a wireless data communication technology that enables very-long-range transmissions (more than 10 km in rural areas) with low power consumption. It uses license-free sub-gigahertz radio frequency bands as the 169 MHz, 433 MHz, 868 MHz for Europe and 915 MHz for North America. The technology can be divided in two parts:

• LoRa: the physical layer,
• LoRaWAN (Long Range Wide Area Network): the upper layers.

Here the code:

	Code: https://github.com/lemariva/uPyLora

This is my first review on a product that I bought. I hope you enjoy it! Advices and tips are welcome! Please leave me them in the comment section!

Introduction

At the beginning of March I supported the Kickstarter campaign called RasPad. I pledged for the Super Early Bird - RasPad which includes:

• Power Adapter
• RasPad Without Raspberry Pi

I didn't want the RasPad Kit because I had a Raspberry Pi B+ that I wasn't using.

The estimated delivery was May 2018, but as it usually happens with the Kickstarter campaign, it was delayed and arrived last week (12.09.2018).

Fig. 1: RasPad

There are lot of tutorials about connecting the ESP32 to a cloud service, but I planned to connect these boards using MicroPython directly to the cloud. That means, I didn't want to use a hardware or software bridge. I wanted to use the Google IoT Core, but MicroPython doesn't support JSON Web Token (JWT), which is needed for the device authentication. I tried to write the library myself, but it didn't work, because of the needed dependencies and the small memory available on the ESP modules. But, I found Zerynth. Zerynth supports JWT and using it, it is possible to connect the ESP32 directly to the Google IoT Core. The company Zerynth defined its product as "the middleware for IoT and Industry 4.0" and the ecosystem was stable as far as I tested it. The IDE (Zerynth Studio) can be a little bit improved, but it works well enough.

Zerynth is neither free nor open-source but every new user gets a welcome pack with 10 Zerynth VM licenses with FreeRTOS (5 Starter and 5 Premium) for free (more info here). If you need to register more sensors, you can use the store to purchase the additional licenses.

Important NOTE: I didn't get any money to promote Zerynth, I just wanted to use Python to connect the ESP32 directly to the Google IoT Core and this was the only option that I've found. If you know another one, please comment this post or send me a message. Thanks!

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!
• Hacking: ESP32 and Captive Portal using MicroPython
• MicroPython: Geolocation using WLAN
• MicroPython: ESP32 and Amazon Echo (Alexa) - Switching LED Colors
• MicroPython: Vu meter using WS2812B and SPW2430
• MicroPython: Weather Report using NEO-M8N
• MicroPython: Christmas lights!
• MicroPython: Camera stabilisation application
• MicroPython: ESP32 sending data using LoRa (NEW 07.10.18)

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.