## Ambient Light (Arduino Project)

This blog post explains the technical details of my Ambient Light project. If you don’t know what this project is about, watch the following video first: Video summary: Sometimes a screen is just a light spot in a dark room. To make the entire scenery more appealing, I created my own, Arduino-powered ambient light. A PC software (written …

## Guess Solutions of Polynomials

For a given polynomial of $n$th degree $$P_n(x)=\sum_{i=0}^n a_ix^i = a_nx^n+a_{n-1}x^{n-1}+…+a_1x+a_0$$ you can guess rational solutions $x$ for the corresponding problem $P_n(x)=0$ by applying the following two rules: $$x=\frac{p}{q}\text{, with } p \in \mathbb{Z} \land q \in \mathbb{N}\land p\mid a_0 \land q\mid a_n$$ $$\lvert x\rvert\le2\cdot \max\left\lbrace \sqrt[k]{\frac{\lvert a_{n-k}\rvert}{\lvert a_n\rvert}}, k=1, …, n\right\rbrace$$ Example The equations above might …

## Install Node SerialPort on Raspberry Pi

Since I had a lot of trouble installing the npm package serialport on my Raspberry Pi B Rev 1 (and Rev 3), I want to share how it eventually worked. Enable serial port usage by adding  enable_uart=1 to the file /boot/config.txt. If the normal  npm install serialport doesn’t work for you try the following. Install Node 6.x …

## Get into Orbit Without Lateral Acceleration

When I was about 6 years old, my dad explained to me that there was no possibility to shoot something right into orbit from the Earth’s surface. He said it was always necessary to accelerate sideways to reach orbit. At that time I did not really understand what he meant. However, later in physics class I …

## Die drei ??? Telegram Bot

Since the publisher Europa uploads new Die drei ??? episodes on Spotify quite frequently, I have been wanting to get an update every time they upload something new. For me the most convenient way to be notified is to get a message on my smartphone. The free messenger Telegram is predestinated for that task because of its open API and bot …

## Buzz Wire TFT (Teensy Project)

Arduino powered Version of the game Buzz Wire with a TFT touch screen. This project was developed for Denk Development‘s customer Kreative Kiste. Features Single- and multiplayer Multiplayer scoreboard Touchscreen name input Video The code itself was written in June 2016; the video was recorded on October 2, 2016. Weblinks Ronnie Berzins (Kreative Kiste) Denk …

## ABAP Objects Quick Reference

This is the second (and final) part of a quick reference for the programming language ABAP. Extending the first part, this one is primarily focusing on ABAP’s object oriented programming features, like classes, OOP-exceptions, and inheritance. The first part can be found here: ABAP Quick Reference Encapsulation using function groups FUNCTION-POOL s_person. * age is a global …

## ABAP Quick Reference

This is the first of two posts, providing a quick reference for ABAP developers. It primarily consists of code examples and doesn’t include major object oriented programming features, introduced in newer language versions. The second part of this series, targeting OOP related topics, can be found here: ABAP Objects Quick Reference ABAP (Advanced Business Application …

## Trigonometric Functions Formulary

This formulary has been created during the online onboarding process at Baden-Wuerttemberg Cooperative State University (DHBW). It is suitable for the related online tests and might be helpful for other people, seeking for formulas in this field of mathematics. Basics \begin{array}{l} \tan x = \frac{{\sin x}}{{\cos x}}\\ \cot x = {\tan ^{ – 1}}x = \frac{{\cos x}}{{\sin …

## Node.js: Develop on Mac, Run on Raspberry Pi

For me the solution for productive Node.js development on Mac, with code execution on a Raspberry Pi was usage of Samba. After following the steps you will be able to develop Node.js applications right on your Mac, execute them on your Raspberry Pi (just by pressing cmd+S) and see the console output and errors on your …