• 03
      Sep - 2019

      Cloud Platforms
      7 min | 4846

      #GCP: Running OpenProject almost FREE

      Cloud Platforms | 7 min | 4846

      google cloud platform
      management software

      The last days, I was looking for an online project management tool with bug tracking system. The best platform that I know is Jira from Atlassian. Jira offers a bug tracking and agile project management, however, it costs between $8.33 and $10 (annual/monthly payment) for the standard version with under 10 accounts. We use Jira in Finealyze and I am very happy with it, but I was looking for a free alternative for myself. Then, I found OpenProject, which describes itself as "the leading open source project management software".

      OpenProject is offered in three different ways: Community, Cloud an...

    • 27
      Aug - 2019

      Deals, Raspberry Pi
      3 min | 11079

      #Raspberry Pi: Displaying images on an E-Ink screen

      Deals, Raspberry Pi | 3 min | 11079

      e-ink display
      raspberry pi

      Last week, I published an article about the Raspberry Pi and an e-ink display:

      This time, this tutorial is about processing and displaying images on the 7.5" e-ink screen as shown in Fig. 1b.

      Waveshare® 7.5" E-ink Screen connected to a Raspberry Pi
      Fig. 1a: E-ink Screen connected to a RPi
      running ePaperWidgets
      Fig. 1b: Banggood's 13th anniversary
      original image here

      Hardware & Software

      You find here a list of hardware and software that you could use for this tutorial:

      E-ink Screen
      • Waveshare® ...
    • 25
      Aug - 2019

      Raspberry Pi
      4 min | 8074

      #Raspberry Pi 4B: How much faster is the new CPU?

      Raspberry Pi | 4 min | 8074

      n-queens problem
      raspberry pi 3 B plus
      raspberry pi 4b

      On July 4th, I ordered a Raspberry Pi 4B from Reichelt. On July 17th, I received the board, but it was broken, and a month later, finally I received a new board that seems to work OK :).

      The new Raspberry Pi 4B has a lot of upgrades and one of the most important ones is the RAM: You can choose between three models (1GB, 2GB and 4GB). But, another main change is the CPU and the RAM bus: they changed from a Cortex-A53 64-bit (3B+/3A+) to a Cortex-A72 64-bit, both ARMv8, and from LPDDR2 SDRAM to LPDDR4 SDRAM. Thus, the CPU clock was increased to 1.5GHz (0.1GHz more) and the memory frequency to 2...

    • 21
      Aug - 2019

      Raspberry Pi
      7 min | 13020

      #Raspberry Pi: an E-Paper display with Widgets

      Raspberry Pi | 7 min | 13020

      e-ink display
      google apis
      google calendar
      raspberry pi
      raspberry pi zero

      E-paper or e-ink displays are becoming more common in recent days. You can find them e.g. on readers, clocks and sensors. Thus, I looked for an e-ink display for the Raspberry Pi and I found the Waveshare® 7.5" E-ink Screen.

      There are many projects with an e-ink display and the Raspberry Pi, but I first tried with an ESP32 and MicroPython. That solution didn't work (something was not working with the reset voltage - too much signal noise). So, that remains a work in progress and I will use this board. But now, in this tutorial, I uploaded a solution for the Raspberry Pi.

       Waveshare® 7.5" E-ink Screen connected to a Raspberry Pi
      Fig. 1: Wa...
    • 20
      Aug - 2019

      4 min | 9953

      #MicroPython: VSCode IntelliSense, Autocompletion & Linting capabilities

      MicroPython | 4 min | 9953

      visual studio code

      Last December, I wrote an article telling you that I was switching from Atom.io to Visual Studio Code to program MicroPython. Nowadays, I'm still using VSCode and the PyMakr extension. The latter enables the communication to a board running MicroPython using the built-in command line REPL. Thus, I can run a single file on my board, sync my entire project or directly type and execute commands using the Terminal on VSCode. However, I was missing some of the main features of VSCode, namely IntelliSense, autocompletion, and linting capabilities. Last month, BradenM contacted me and told me that he...

    • 13
      Aug - 2019

      Home Automation, Raspberry Pi
      3 min | 18829

      #Zigbee: Flashing a CC2531 dongle using a Raspberry Pi

      Home Automation, Raspberry Pi | 3 min | 18829

      aqara sensors
      door sensor
      home assistant
      raspberry pi
      xiaomi gateway
      xiaomi sensors

      Last April, I published a tutorial about connecting the Aqara sensors to a Raspberry Pi without using the Xiaomi Gateway. To make that possible, I needed a CC Debugger to flash the TI CC2531 Zigbee Dongle. This debugger was used only one time, and then the Zigbee-USB dongle worked without any problem.

      In this article, I will cover a way to flash the CC2531 without the CC Debugger. This reduces project costs (about $10 for debugger + cable adapters) and waiting time. Usually, you wait 30 days to get a low cost version of the debugger (using the cheapest shipping option). Let's start!


    • 02
      Aug - 2019

      Raspberry Pi
      2 min | 5755

      #Raspberry Pi 4B: Where were the quality controls?

      Raspberry Pi | 2 min | 5755

      board broken
      capacitor broken
      quality control failed
      quality problems
      raspberry pi
      raspberry pi 4b
      tantalum capacitor

      On July 4th, I ordered a Raspberry Pi 4B. To be honest, I really didn't/don't need a new Raspberry Pi, I don't have any specific task for it, but I saw some cool stuff on the Internet, and I said: Ok, I need one! Thus, I bought the 4GB model on Reichelt. The expected delivery date was on July 10th but, I had to wait a little longer and I got it on July 17th! Everything was ok, and I got the following closed and sealed box (see Fig. 1):

      Fig. 1: Box of the Raspberry Pi Model 4B (4GB RAM)

      But, as soon as I opened the box, my joy faded! :( With a quick visual control, I checked tha...

    • 21
      Jul - 2019

      General, MicroPython, Miscellaneous
      1 min | 1760

      #Collector: Things that I recently bought - XIAOMI Wowstick & ESP32 8MB PSRAM

      General, MicroPython, Miscellaneous | 1 min | 1760

      development boards
      electric screw driver
      esp32 8mb psram
      misc article
      xiaomi wowstick

      This is a really misc. small article. Two month ago, I bought on Banggood two articles that I wanted to show you, but this time, these are not connected to an application, code or a detailed product review. This is only a misc. article to describe my purchase: The Xiaomi Wowstick Screw Driver and the TTGO ESP32 WROVER with 8MB PSRAM.


      Xiaomi Wowstick

      If you are looking for a very small electric screw driver, then the Xiaomi Wowstick is an option for you. It includes everything that you need except the batteries. You need two AAA batteries and you can start disarming toys, clocks, cell...

    • 14
      Jul - 2019

      General, Product Reviews
      5 min | 2327

      #Timeular: Tracking your time using an Octahedron

      General, Product Reviews | 5 min | 2327

      access to data
      getting things done
      product review
      time tracker
      time tracking system

      First of all, this article is a product review which was/is not supported by Timeular GmbH or similar. I bought the product two weeks ago, because I wanted to test it. I missed out the Kickstarter campaign (2016) and the regular price for the octahedron was too expensive for me.

      Timeular application: Analytics Dashboard
      Fig. 1: Timeular application

      This summer, the tracker is on sale with up to 50% discount and I bought the basic plan. I got an octahedron -called tracker- which connects to the Timeular application (Mac, Win...

    • 09
      Jul - 2019

      Home Automation, Product Reviews, Raspberry Pi
      2 min | 5925

      #Zigbee: Reading Xiaomi Sensors with a Raspberry Pi (no Xiaomi gateway needed!)

      Home Automation, Product Reviews, Raspberry Pi | 2 min | 5925

      home assistant
      home automation
      product review
      raspberry pi 3 B plus
      xiaomi gateway
      xiaomi sensors

      I've been very busy the last weeks. I moved to a new apartment and I was living between moving boxes. Four days ago, I managed to put my desk together and now I have some time (not a lot) to write a new article.

      Last month I've received from GearBest two Aqara sensors:

      These sensors use Zigbee and I connected them to a Raspberry Pi running Raspbian OS and a dockerized version of Home Assistant (DIY tutorial). This connection was made without using any Xiaomi gateway (DIY tutorial).

      Hardware and Software

    • 11
      May - 2019

      12 min | 2146

      #Analytics: Beautiful Python using PEP8

      Analytics | 12 min | 2146

      programming languages

      PEP-8 (sometimes PEP 8 or PEP8) is a coding standard and style guide for readability and long-term maintainability of code in Python. It was written in 2001 by Guido van Rossum, Barry Warsaw, and Nick Coghlan and provides guidelines and best practices on how to program Python code. PEPs stand for Python Enhancement Proposals, and they describe and document the way Python language evolves, providing a reference point (and in some way a standardization) for the pythonic way to write code.

      This tutorial presents some of the most important key points of PEP-8. If you want to, you can read the ful...

    • 27
      Apr - 2019

      Analytics, Hacking
      1 min | 1351

      #Docker: Docker hub has been hacked

      Analytics, Hacking | 1 min | 1351

      data leak
      docker hub

      Attention Docker Hub users - Docker Hub has been hacked!

      An email containing the following highlight was sent to the users whose account data may have been exposed.

      During a brief period of unauthorized access to a Docker Hub database, sensitive data from approximately 190,000 accounts may have been exposed (less than 5% of Hub users). Data includes usernames and hashed passwords for a small percentage of these users, as well as Github and Bitbucket tokens for Docker autobuilds (full email).

      If you got this email you should (and if you didn't receive that email, do it too ;)):

      1. Change your...

    • 16
      Apr - 2019

      Raspberry Pi
      4 min | 5054

      #Edge-TPU: Hands-On with Google's Coral USB accelerator

      Raspberry Pi | 4 min | 5054

      coral usb accelerator
      machine learning
      raspberry pi
      teachable machine
      tensorflow lite

      Last week, the Coral team released updates to the Coral platform to "address customer feedback and make it easier to use the products and tool-chain". The Python API has now the ability to run multiple models in parallel, using multiple Edge TPUs.

      Thus, due to the multiple changes, I updated the Docker image lemariva/raspbian-edgetpu which includes the Edge-TPU libraries for Raspberry Pi 3 B+, Jupyter Notebooks and some other interesting libraries (check the Dockerfile).

      Fig 1: Coral USB Accelerator, Jupyter and some training objects

      The base Docker image remained balenalib/ras...

    • 13
      Apr - 2019

      Home Automation, Raspberry Pi
      4 min | 13007

      #Raspberry Pi: Xiaomi Sensors & Home Assistant (Hass.io)

      Home Automation, Raspberry Pi | 4 min | 13007

      home assistant
      home automation
      raspberry pi

      Last week, I published an article about using Xiaomi sensors without a Xiaomi Gateway. The gateway/hub can be replaced with a Raspberry Pi and a USB-ZigBee dongle. You find the instructions here: #ZigBee: Xiaomi Sensors using Raspberry Pi (without Gateway!).

      As you can read in that article, two repositories are available to connect and process the data from the Xiaomi sensors. Additionally, Zigbee2mqtt can be connected to Hass.io. Well, I didn't want to use HassOS (the OS on which hass.io runs), but I wanted to use Hass.io running on Raspbian, otherwise with Home Assistant running as an appli...

    • 12
      Apr - 2019

      MicroPython, Product Reviews
      5 min | 7507

      #MAiX Dock & MicroPython: Hands-On with low power AI at the edge

      MicroPython, Product Reviews | 5 min | 7507

      edge device
      low port ai
      low power ai
      maix dock
      object classifier

      This week, I received from Seeed Studio a MAiX Dock to review it. The main board of the kit includes a Sipeed M1w which is a compact module like the ESP32 but based on the Kendryte K210 dual core RISC-V processor. It is designed for low power artificial intelligence workloads, such as face detection, object recognition, or audio processing. There are two type of modules: the Sipeed M1 and M1w, the last one includes WIFI connectivity.

      The main features of the MAiX Dock boards are:

      1. Display I/F – An FPC24P socket for 8-bit MCU LCD
      2. Camera I/F- An FPC24P socket for DVP camera
      3. Storage – micro SD s...