Projects on the orange bench

by Dirk Grappendorf

Welcome to

About me, my past and ongoing projects and other things i'm interested in.
Look around and feel free to leave me a comment.

Featured Projects

  • 6502 Homecomputer

    6502 Homecomputer
    This is a project that I've often started, but haven't completed until now because i knew that it would take quite a long time: building my own 8-bit home computer from scratch. The idea was to design a computer like the C64, almost only using parts that were available when this computer was manufactured.
  • Analog Computer Construction Kit

    Analog Computer Construction Kit
    Inspired by Dr. Vogels Home Brew Analog Computer , this kit consists of various 100x60 cm PCB cards which can be connected together with 2.54 mm jumpers. Connect the various input and outputs of generators, adders, integrators and multipliers to compute different mathematical functions.
  • Sunrise Alarm Clock

    Sunrise Alarm Clock
    A wake-up light, built with Elixir, Nerves, running on a Raspberry Pi Zero. This project explores how Elixir/Erlang OTP can be used to develop robust and thoroughly tested embedded systems.
  • Smarkant

    This work extends the IKEA-Hackant project from Robin Reiter, who reverse engineered the controller board of an IKEA Bekant motorized adjustable table. In my project i connected an ESP-12F module (ESP8266) to the Arduino, which gives us WiFi and quite some processing power to add additional IoT functions to the Bekant table.


Tech Radar

For everyone interested in the technologies that i use, i created a Tech Radar. Feel free to write me about technologies that you use, that you no longer use or that you are considering using in the future.


Sunrise Alarm Clock - Update

I upgraded my Sunrise Alarm Clock tutorial project to the latest Elixir, Nerves and Phoenix versions.


Spin FV-1 based effects module for Eurorack systems

A Eurorack effects module based on the Spin FV-1 IC.

The circuit is essentially the reference design as described in the data sheet with some additional standard input and output signal level translation. I've also added a slightly over-engineerd program number display and a clunky program switch.


About me

I'm a senior Software Architect, Scrum Master, Team Lead and Software Developer currently located in Dortmund, Germany.
I'm always interested in new innovative and challenging tasks, so feel free to browse through my resume and leave me a note.