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Getting the .ipynb Notebook File Location From a Running Jupyter Lab Notebook

Sun, 29 Jun 2025 23:42:00 +0100

If you need to get the path of the ipynb file in a running #Jupyter notebook, this one-liner will do the trick. It seems chatgpt is confused, and a bunch of other approaches on the web look fragile and/or unnecessarily complex to me.

8seg Technical Overview

Tue, 26 Dec 2023 15:26:00 +0100

8seg is a large-scale LED light art installation that displays text on a 1.5 meter high, 30 meter wide 8-segment display made from cheap LED tape.

KiMesh

Wed, 04 Oct 2023 23:42:00 +0200

KiMesh is a KiCad plugin that automatically creates security meshes with two or traces covering an arbitrarily-shaped outline on the board.

Ubiquiti EdgeRouter on Deutsche Telekom GPON Fiber

Mon, 21 Feb 2022 20:00:00 +0100

Short tutorial on getting a Deutsche Telekom GPON internet connection running using a SFP ONU unit in an Ubiquiti EdgeRouter.

New Paper on Inertial Hardware Security Modules

Tue, 23 Nov 2021 23:42:20 +0100

Paper announcement: We have published a paper on how you can DIY a tamper-sensing hardware security module from any single-board computer using a moving tamper-sensing mesh made from cheap PCBs.

Kicad Mesh Plugin

Tue, 18 Aug 2020 13:15:39 +0200

I wrote a little KiCad plugin that you can use to create security meshes, heaters and other things where you need one or more traces cover the entire surface of a PCB. The plugin supports arbitrary PCB shapes, cutouts, and can route around existing footprints and traces on the PCB.

Private Contact Discovery

Sat, 22 Jun 2019 10:30:00 +0800

I gave a short introduction into Private Contact Discovery protocols at our university workgroup.

Hardware Security Module Basics

Fri, 17 May 2019 15:29:20 +0800

I gave a short introduction into Hardware Security Modules at our university workgroup, including an overview on interesting research directions.

How to talk to your microcontroller over serial

Sat, 19 May 2018 08:09:46 +0200

Scroll to the end for the TL;DR.

In this article I will give an overview on the protocols spoken on serial ports, highlighting common pitfalls. I will summarize some points on how to design a serial protocol that is simple to implement and works reliably even under error conditions.

If you have done low-level microcontroller firmware you will regularly have had to stuff some data up a serial port to another microcontroller or to a computer. In the age of USB, an old-school serial port is still the simplest and quickest way to get communication to a control computer up and running. Integrating a ten thousand-line USB stack into your firmware and writing the necessary low-level drivers on the host side might take days. Poking a few registers to set up your UART to talk to an external hardware USB to serial converter is a matter of minutes.

Thor's Hammer

Thu, 03 May 2018 11:59:37 +0200

In case you were having an inferiority complex because your friends' IBM Model M keyboards are so much louder than the shitty rubber dome freebie you got with your pc... Here's the solution: Thor's Hammer, a simple typing cadence enhancer for PS/2 keyboards.

Your browser does not support the HTML5 video tag.

A demonstration of the completed project. h264 download / webm download

The connects to the keyboard's PS/2 clock line and briefly actuates a large solenoid on each key press. An interesting fact about PS/2 is that the clock line is only active as long as either the host computer or the input device actually want to send data. In case of a keyboard that's the case when a key is pressed or when the host changes the keyboard's LED state, otherwise the clock line is silent. We ignore the LED activity for now as it's generally coupled to key presses. By just triggering an NE555 configured as astable flipflop we can stretch each train of clock pulses to a pulse a few tens of milliseconds long that is enough to actuate the solenoid.

32-Channel LED tape driver

Wed, 02 May 2018 11:31:14 +0200

Together, a friend and I outfitted the small staircase at Berlin's Chaos Computer Club with nice, shiny RGB-WW LED tape for ambient lighting. For this installation, I made a 32-channel LED driver that achieves high dynamic range on all 32 channels using a cheap microcontroller by using Binary Code Modulation.

Wifi Led Driver

Wed, 02 May 2018 11:31:03 +0200

After the `multichannel LED driver`_ was completed, I was just getting used to controlling LEDs at 14-bit resolution. I liked the board we designed in this project, but at 32 channels it was a bit large for most use cases. Sometimes I just want to pop a piece of LED tape or two somewhere, but I don't need a full 32 channels of control. I ended up thinking that a smaller version of the 32-channel driver that didn't require a separate control computer would be handy. So I sat down and designed a variant of the design with only 8 channels instead of 32 and an on-board ESP8266_ module instead of the RS485_ transceiver for WiFi connectivity.

Docutils System Messages

System Message: ERROR/3 (<stdin>, line 1); backlink

Unknown target name: "multichannel led driver".

System Message: ERROR/3 (<stdin>, line 1); backlink

Unknown target name: "esp8266".

System Message: ERROR/3 (<stdin>, line 1); backlink

Unknown target name: "rs485".

LED Characterization

Wed, 02 May 2018 11:18:38 +0200

Preface

Recently, I have been working on a small driver for ambient lighting using 12V LED strips like you can get inexpensively from China. I wanted to be able to just throw one of these somewhere, stick down some LED tape, hook it up to a small transformer and be able to control it through Wifi. When I was writing the firmware, I noticed that when fading between different colors, the colors look all wrong! This observation led me down a rabbit hole of color perception and LED peculiarities.

8seg

Mon, 01 Jan 0001 00:00:00 +0000

8seg is an experimental textual display. It is made from a 45m by 1.5m large lacework banner that can be put up in a variety of spaces, conforming to the space's size and shape through bending and folding.

About jaseg

Mon, 01 Jan 0001 00:00:00 +0000

About

Hej, I'm Jan, or jaseg. At the moment I'm doing a PhD (Dr.-Ing.) at TU Darmstadt in Computer Science, specializing on Hardware Security. This is my personal website where I publish things that I find interesting.

I self-host my code at git.jaseg.de, but I am also on github and on gitlab. I use github for issue tracking for some of my projects such as gerbolyze and python-mpv. I maintain the python-mpv and gerbolyze python packages on PyPI. Release tags on these two repositories are signed with the release signing key found on github and below.

Gerbolyze

Mon, 01 Jan 0001 00:00:00 +0000

Gerbolyze is a tool that allows the modification of Gerber PCB artwork with a vector graphics editor like Inkscape. Gerbolyze directly converts between SVG and Gerber, and accurately reproduces details that other tools can not.

Gerbonara

Mon, 01 Jan 0001 00:00:00 +0000

Gerbonara is a user-friendly, powerful tool for reading, writing, modification and rendering of Gerber PCB artwork from the command line or from Python code. Gerbonara supports the Gerber dialects of all industry-standard EDA tools.

Impressum

Mon, 01 Jan 0001 00:00:00 +0000

Impressum

Sebastian Götte
c/o Praxis Dr. Götte
Krankenhausstr. 1a
54634 Bitburg
imprint@jaseg.net

Inhaltlich Verantwortlicher gem. § 55 II RStV: Sebastian Götte (Anschrift s.o.)

Lizenz dieser Seite

Dieses Werk ist lizenziert unter einer Creative Commons Namensnennung - Nicht-kommerziell - Weitergabe unter gleichen Bedingungen 4.0 International Lizenz (CC-BY-NC-SA) .

Haftungsbeschränkung für Inhalte der Website

Gemäß § 7 Abs. 1 TMG ist der Verantwortliche der Website i. S. v. § 5 TMG für eigene Informationen, die er zur Nutzung bereithält, nach den allgemeinen Gesetzen verantwortlich.

lolcat-c

Mon, 01 Jan 0001 00:00:00 +0000

lolcat-c is a small, high-performance re-implementation of the lolcat rainbow cat utility. lolcat-c is meant as a lolcat that you can actually use in production. It is fast, not slowing down whatever you pipe through it, and it robustly handles real-world terminal output including escape sequences.

python-mpv

Mon, 01 Jan 0001 00:00:00 +0000

python-mpv is a small, ctypes-based Python library wrapping the libmpv media player library. Despite its small size and simple API, python-mpv allows advanced control over libmpv and beyond simple remote control of mpv can be used to embed mpv in OpenGL, Qt, and GTK-based Python applications.

svg-flatten

Mon, 01 Jan 0001 00:00:00 +0000

svg-flatten is a command-line utility that performs vector occlusion and clipping on SVG files, producing a flattened SVG file without overlapping elements, without changing what the file looks like. svg-flatten is used as a part of gerbolyze.

wsdiff

Mon, 01 Jan 0001 00:00:00 +0000

wsdiff is a command-line utility that produces self-contained, syntax-highlighted, HTML-formatted diffs that support both unified and side-by-side diffs from a single source file using nothing but CSS magic.