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Blog Spot

Blog Spot

This is not a BLOG, where short pieces of information are published on a regular basis. Rather, it's a place for me to dump things onto the internet that didn't fit in other places. Call it "private digital landfill" if you like. It's organized with old stuff at the bottom and more recent stuff near the top.

Table of Content

  1. Chess
  2. The SemWare Editor
  3. Speakerbench
  4. Audio Streamer Upgrade
  5. Think Global Background Picture
  6. ALMA - AISE 2017
  7. Chapter for Book
  8. Streaming Audio
  9. Linux
  10. Batch programming tutorial

2025-07-05: Chess

Although I am quite bad at chess (I am not practicing), I find the game interesting. Maybe my years living in Norway add to this, because chess champion and grandmaster Magnus Carlsen was frequently in the news. I found the work by Oscar Toledo particularly fascinating in that he created a chess engine that plays by the rules (including castling, en passant, and promoting of pawns) within 1 kilobyte of memory, i.e., the brain size of a fruit fly (maybe), yet it is said to have a chess rating of about 1300, which means it will beat you every time, unless you start practicing. A skilled person in chess should be able to beat the game.

I found a version of Oscar Toledo's chess engine coded in Javascript embedded into a web page with some nice CSS for showing a pretty chessboard. This game takes up a few more kilobytes, but I think it is worth the extra space. The code I found had one 'error' in that the fields of the chessboard were wrongly numbered (the letters A-H were in the opposite direction), so I modified the code. Here is my modified code: nanochess.

Feel free to download the code and use it offline (right-click and choose Save link as). The code is in principle human readable (in essence open source), but to minimize the code, each variable is a single letter, so it's cryptic. For comprehending it, you probably will need to buy Oscar Toledo's book about the subject. How about running it and seeing if you can beat a fruit fly brain (about 100000 neurons) in chess? I claim no copyright or other rights to this code. It all belongs to Oscar Toledo.


2023-01-07: The SemWare Editor

My favourite code editor is TSE ('Tessie') for The SemWare Editor. Many of you may never have heard about it, but for me it started back in the days of MS-DOS, and the name of the editor was QEdit. The editor was restricted by DOS memory limits (640 kb of main RAM). I could easily program the editor to do many of the editing tasks I needed done, because it had a powerful macro language, and it was super fast (predominantly coded in assembly language). Sammy Mitchell (of SemWare) faced modern times (of Windows, and no memory limits) by reworking his code from scratch, now with a frame of the C language, but gauging from the speed of the editor, still infused with assembly code, now with an even more powerful macro language which can do almost anything - including communicating with your coffee machine to brew a cup of coffee for you (if it's hooked up to your LAN). I paid for TSE in 2004 and am still a happy user.

TSE became freeware sometime in 2021 or early 2022 and you can download it from the website of Carlo Hoogeveen (who is also an avid macro programmer for TSE). Surprisingly TSE is still being actively developed. TSE has many powerful features, but one special feature is cut and paste of code across columns and rows. Something I need but haven't found in any other editor (I've tried many). I guess that is just how it is with editors, once you are hooked, there is no way to turn around.


2020-04-05: Speakerbench

A couple of months back, Jeff Candy and I launched a new web site, named Speakerbench (external link). This is a web application for assisting in speaker design, in particular measuring advanced parameters by using the dual-added-mass approach. More will come.


2019-01-19: Raspberry Pi and ApplePi Music Streaming Audio Upgrade

This DIY project describes how I've built a high-end replacement for my Squeezebox Touch streamer using a Raspberry Pi and a suitable DAC HAT-module.


2018-10-27: "Think Global" - Pixel Art, Stylized World Time Zone Map

Suitable as background image / wallpaper for your PC.

I looked several times for one of those time zone maps for my PC, like what came with the old IBM Thinkpads, but I only found bad ones (maybe upscaled from lower resolution images), and almost none that fitted to my 1920 x 1080 resolution. This summer I gave up and started to make my own. Here's the result, I hope you enjoy it and if not, that's just too bad: Think_Global_FHD.png - Made by Claus Futtrup © Copyright 2018. Here's some map facts.


2017-02-23: ALMA - AISE 2017

At the ALMA International Symposium and Expo 2017 (AISE2017) Jeff Candy and I presented a paper titled "Physical Accuracy and Modeling Robustness of Motional Impedance Models."

The paper / presentation is available for download here: ALMA-2017.pdf. Enjoy!


2016-04-29: Chapter for Book

It was either late 2011 or very early 2012. A German publisher approached me and asked if I would write a chapter for a book. Today, more than 4 years later, I've annually gone through the chapter and updated it, but the book will not materialize. So instead I received permission to publish the chapter here.

The concept behind the book itself was inspired by a garden book, if I remember correctly, where several authors wrote chapters. They may be controversial. Preferably something that catches a debate. Each author was free to choose whatever subject they wanted to write about.

The chapter is 24 pages of text: Book_05_Futtrup.pdf. Enjoy!

This chapter is somewhat like a "layman's" version of the AES paper I wrote in 2011, targeting a nontechnical audience, (almost) without the math. It adds historical background and some idea about how to ensure a nice impulse response by using Group Delay. I hope it's good for learning to understand what goes on in a loudspeaker. If you're engineering loudspeakers, using T/S parameters, I think you'll find this chapter interesting. I'd like to move forward with additional advancements in simulation, but I believe the presented FDD model is very good for explaining limitations within the classical Thiele/Small modelling.


Streaming Audio

This text on how to setup your hardware as well as your music library and using software to tag the files is from 2009 and may appear a bit old by now. Nonetheless, it is one of the most popular pages on my website so it must still be useful to a lot of people in the world.

Streaming Audio:

I have experimented with streaming audio, and eventually purchased a Logitech Squeezebox Duet. Here you can read about my experiments with streaming audio. Later, my setup has been changed for a Logitech Squeezebox Touch.


Linux

I was active in the Linux community from somewhere around 2005 and until 2008. Since the support for Microsoft Windows 7 has dropped (for example, I can't get an updated PowerShell) and only security updates are still rolling in, I just might bring my old laptop computer back to life with Linux again.

Linux:

I've been an active Linux user for a while, predominantly involved in the Zenwalk Linux project. For example, I wrote a welcome message for Windows users. With more than 100000 views it is safe to say that this text was very popular and maybe still is. It was posted on several other sites and translated into other languages. Unfortunately, as of October 2013 the Zenwalk Linux homepages are defunct and may not return.

I have recovered the page from archive.org. The page layout has been reworked to fit this web site. You can see the reworked page here: Welcome Windows Users (reworked).


Batch programming tutorial

This tutorial has existed on my web pages forever, yet it is so old it doesn't seem appropriate to put it on my front page anymore. Much of the material is from 1995. I'm proud to say people around the world have used the code inside. For example, one script was adopted by LaTeX (F_NAME.BAT - and it is still available on CTAN).

Batch programming tutorial:

At some point I decided to write a tutorial in batch programming (for DOS), and it became quite advanced. It is suitable for anybody who wants to write a little batch-file, or a large one. The tutorial contains examples that tend to look like magic in the control of the batch language, but even a newbie should be able to read it because it starts out really easy (no steep learning curve). Check out batching.zip. (P.S. Note that it is made for DOS 5.0 up to 6.2, not 100% compatible with all cmd terminals in MS Windows)