A few weeks ago I visited Berlin. A fantastically interesting city, and much more affordable and accessible than places like New York or London. However, it is almost comical how much of what you see ends up being about either the Third Reich or the Cold War and the DDR. The war in Ukraine was also noticeably present.Continue reading “Berlin – Cold War, Third Reich, and Ukraine”
I recently made a trip to the US to look at some interesting things like the USS Intrepid, the architecture or New York City, and Battleship Cove. Battleship Cove is located in Fall River, Massachusetts, and hosts the South Dakota-class battleship USS Massachusetts. Additionally, the site holds the destroyer USS Joseph P Kennedy, the submarine USS Lionfish, and the East German missile corvette Hiddensee. Given that I only had an afternoon there, I ended up only looking at the battleship with a brief run through the submarine. It was that good, especially in company with an old friend who also had read up on how the ship worked.Continue reading “USS Massachusetts and Battleship Cove”
When writing software that uses any kind of API or hardware functionality, sooner or later there will be questions about what a particular API call or hardware operation is supposed to do. In principle, such questions should be answered by referring to the specification (and user documentation). I am a firm believer in writing readable and clear specs and keeping software coding to follow the spec, as that ensures future compatibility. But reality is not that simple. Things are generally better today than they used to be, though. Reading up a bit on the history of my first computer (the ZX Spectrum), I found some rather interesting cases of spec vs implementation, and “discovered functionality”.Continue reading “Code to the Spec(trum) or the Implementation”
A few days ago, Sir Clive Sinclair died. I owe him, or rather his most successful product, my career as a computer scientist. I bought myself a ZX Spectrum in my early teens, taught myself how to program it, and never looked back. The ArsTechnica obituary calls the Spectrum a “gaming computer”, and I guess that is mostly fair. Can’t say I ever used it for more than playing games or programming games.Continue reading “Thank You, Sir Clive Sinclair”
When I recently turned 50, a friend of mine gave me a book that was about as old as me – Timesharing System Design Concepts, by Richard W Watson. The copyright date is 1970, but the publishing date found online 1971. The book covers the hardware support and software techniques needed to provide multiple users with simultaneous access to a computer system. Typically, using remote teletype terminals. It is a wonderful book, reflecting on the state of computer technology around 1970. It shows both how many of the basic concepts we still use today were already in use back then, but at the same time just how far we have evolved computing since.Continue reading “Timesharing System Design Concepts (1970)”
With Covid-19 still a bit of an issue, the summer of 2021 is yet another one for “svemester” (Sverige-semester, or Sweden-vacation). There are plenty of things to see, and one place that I finally got to visit was the old oil refinery at Oljeön in Ängelsberg, home to Engelsbergs oljefabrik and the world’s oldest preserved oil refinery dating back to the mid-1870s. It is a beautiful piece of industrial history, well-preserved and with good guided tours.Continue reading “Oljeön – The World’s Oldest Preserved Oil Refinery”
Back when I was a PhD student working on worst-case execution-time (WCET) analysis, one of the leading groups researching the topic was the “Saarbrücken gang” led by Professor Reinhard Wilhelm. Last year, Professor Wilhelm published a retrospective look on their work on WCET in the Communications of the ACM. It is a really interesting history write-up from the perspective of the Saarbrücken group.Continue reading “Professor Reinhard Wilhelm on the History of WCET Analysis”
The history show (and podcast) of Sverige Radio, Vetenskapsradion Historia, is one of the shows that I subscribe to and listen to regularly. In their look back at 2020, they reminded me of an episode from back in the summer that indirectly introduces what I believe to be the first programmer in Sweden.Continue reading “The First Swedish Programmer (1790s)?”
Continuing on my blog posts about our Hemester (part 1 covered Bodens Fästning), this blog post will cover Hemsö Fästning. Both are fascinating places, but also rather different, and clearly demonstrate the changes from the early 1900s to the Cold War of the 1950s.Continue reading “Hemsö Fästning – Coastal Defense from the 1950s”
Due to Covid-19, this year’s summer vacation involved a “staycation”, or “hemester” as we say in Swedish. We went up north in Sweden, and took the chance to visit some military museums. In particular, the fortresses at Hemsön and Boden (fästning means fortress). Both are fascinating places, but also rather different, and clearly demonstrate the developments from the early 1900s to the Cold War of the 1950s. This post covers Boden, with a separate post for Hemsö released a few days after this post.Continue reading “Bodens Fästning – A Fortress in the North of Sweden”
Recently, we had a discussion at work (in our daily virtual team “fika”) where we reflected on just how many weeks we had been working from home due to the Covid-19 pandemic. It has been quite a few; I last saw the office in week 11, and week 19 is beginning… so I am looking at eight weeks personally. Just how did it all begin? I thought it useful to go back and try to remember how we got to this point. In hindsight, I never thought it would be this huge.Continue reading “Recalling the Beginning of Covid-19 and Work-from-Home”
I heard about the DOOM Game Engine Black Book by Fabien Sanglard on the Hanselminutes podcast episode 666, and immediately ordered the book. It was a riveting read – at least for someone who likes technology and computer history like I do. The book walks through how the ID Software classic DOOM game from 1993 works and the tricks and techniques used to get sufficient performance out of the hardware of 1993. As background to how the software was written, the book contains a great description of the hardware design of IBM-compatible PCs, gaming consoles, and NeXT machines circa 1992-1994. It covers software design, game design, marketing, and how ID Software worked.Continue reading “DOOM Black Book – This is Brilliant!”
Last weekend, the yearly Flygdag (Airshow) of the Swedish Armed Forces took place in Uppsala at Ärna. Huge crowds, but it was still easy to get a good view of the aerial displays that took place. In this blog post, I just wanted to share a few photos.
Thanks to a tip from “Derek” on a previous blog post about a replay debugger from 1995, I was made aware of the reverse execution ability that was available in the Borland Turbo Debugger version 3.0 from 1992! This is the oldest commercial instance of “reverse” that I have found (so far), and definitely one of the oldest incarnations of the idea overall. Thanks to Google and the Internet, I managed to find a scanned copy of the manual of the product, which provided some additional information. Note that the debugger only does reverse execution, but not reverse debugging since you cannot run in reverse to stop at a breakpoint.
Bengt Werner was one of the first people to work on the simulator that would become Simics, way back in 1992. On my Intel Blog, I published an interview with Bengt a while back where we discuss the early days of Simics and the original product vision and use cases.