I would think most of us here at OSNews are aware of VisiOn, the graphical multitasking operating system for the IBM PC which was one of the first operating systems with a graphical user interface, predating Windows, GEM, the Mac, and even the Apple Lisa. While VisiOn was technically an “open” platform anybody could develop an application for, the operating system’s SDK cost $7000 at the time and required a VAX system. This, combined with VisiOn failing in the market, means nobody knows how to develop an application for it.

Until now. Over the past few months, Nina Kalinina painstakingly unraveled VisiOn so that she she could recreate the SDK from scratch. In turn, this allowed developer Atsuko to develop a clean-room application for VisiOn – which is most likely the very first third-party application ever developed and released for VisiOn. I’ve been following along with the pains Kalinina had to go through for this endeavour over on Fedi, and it sure was a wild ride few would be willing (and capable) to undertake.

It took me a month of working 1-2 hours a day to produce a specification that allowed Atsuko to implement a clean-room homebrew application for VisiOn that is capable of bitmap display, menus and mouse handling.

If you’re wondering what it felt like: this project is the largest “Sudoku puzzle” I have ever tried to solve. In this note, I have tried to explain the process of solving this puzzle, as well as noteworthy things about VisiOn and its internals.

↫ Nina Kalinina

The article contains both a detailed look at VisiOn, as well as the full process of recreating its SDK and developing an application with it. Near the end of the article, after going over all the work that was required to get here, there’s a sobering clarification:

This reverse-engineering project ended up being much bigger than I anticipated. We have a working application, yes, but so far I’ve documented less than 10% of all the VisiHost and VisiOp calls. We still don’t know how to implement keyboard input, or how to work with timers and background processes (if it is possible).

↫ Nina Kalinina

I’d love for more people to be interested in helping this effort out, as it’s not just an extremely difficult challenge, but also a massive contribution to software preservation. VisiOn may not be more than a small footnote in computing history, but it still deserves to be remembered and understood, and Kalinina and Atsuko have done an amazing amount of legwork for whomever wants to pick this up, too.

What if you have a Risc PC, but aside from RISC OS, you also want to run Linux? Well, then you have to jump through a lot of hoops, especially in 2025.

Well, this was a mess. I don’t know why Potato is so crashy when I install it. I don’t know why the busybox binary in the Woody initrd is so broken. But I’ve got it installed, and now I can do circa-2004 UNIX things with a machine from 1994.

↫ Jonathan Pallant

The journey is definitely the most rewarding experience here for us readers, but I’m fairly sure Pallant is just happy to have a working Linux installation on his Risc PC and wants to mostly forget about that journey. Still, reading about the Risc PC is very welcome, since it’s one of those platforms you just don’t hear about very often between everyone talking about classic Macs and Commodore 64s all the time.

OK I promised computers, so let’s move to the Tek 4051 I got! Released in 1975, this was based on the 4010 series of terminals, but with a Motorola 6800 computer inside. This machine ran, like so many at the time, BASIC, but with extra subroutines for drawing and manipulating vector graphics. 8KB RAM was standard, but up to 32KB RAM could be installed. Extra software was installed via ROM modules in the back, for example to add DSP routines. Data could be saved on tape, and via RS232 and GBIP external devices could be attached!

All in all, a pretty capable machine, especially in 1975. BASIC computers where getting common, but graphics was pretty new. According to Tektronix the 4051 was ideal for researches, analysts and physicians, and this could be yours for the low low price of 6 grand, or around $36.000 in 2025. I could not find sales figures, but it seems that this was a decently successful machine. Tektronix also made the 4052, with a faster CPU, and the 4054, a 19″ 4K resolution behemoth! Tektronix continued making workstations until the 90s but like almost all workstations of the era, x86/Linux eventually took over the entire workstation market.

↫ Rik te Winkel at Just another electronics blog

Now that’s a retro computer you don’t see very often.

LisaGUI is an amazing project that recreates the entire user interface of the Apple Lisa in the browser, using nothing but CSS, a bit of HTML, and SVG files, and it’s an absolute joy to use and experience. Its creator, Andrew Yaros, has published a blog post diving into the why and how of LisaGUI.

I had been trying to think of a good project to add to my programming portfolio, which was lacking. Finding an idea I was willing and able to execute on proved harder than expected. Good ideas are born from necessity and enthusiasm; trying to create a project for its own sake tends to be an uphill battle. I was also hoping to think of a specific project idea that hasn’t really been tried before. As you may have guessed by the title of this post, LisaGUI ended up being that project, although I didn’t really set out to make it as much as I stumbled into it while trying to accomplish something else.

↫ Andrew Yaros

I’m someone who prefers to run the real thing on real hardware, but in a lot of cases, that’s just not realistic anymore. Hardware like the Apple Lisa are not only hard to find and expensive, they also require considerable knowledge and skill to maintain and possibly repair, which not everyone can do. For these types of machines, virtualisation, emulation, and recreation are much better, more accessible options, especially if it involves hardware and software you’re not interested enough in to spend time and money on them.

I love it when I discover – usually through people smarter than I – an operating system or graphical user interface I’ve never heard of. This time, we’ve got Bellcore MGR, as meticulously detailed by Nina Kalinina a few weeks ago.

I love old computers, and I enjoy looking at old user interfaces immensely. I could spend a whole evening on installing an old version of MS Word and playing with it: “Ah, look, how cute, they didn’t invent scrollbars just yet”. A special place in my heart is taken by user interfaces that were historically significant and yet fell into relative obscurity (like Windows 2 or BTRON).

This is why I absolutely had to try Bellcore MGR. An early windowing system (1984), it was made by the Bell Communications Research, and it looked like Plan 9’s older sister. The system was distributed over the Usenet, ported to every conceivable Unix-like system, including Minix, Linux and Coherent, and – eventually – mostly forgotten. The only two videos on YouTube that have something to do with MGR have a bit over 1000 views combined, and don’t really show it in the best light possible. And I think it’s a crying shame.

↫ Nina Kalinina

The reference to Plan 9 is apt, as MGR definitely seems to function almost exactly like Plan 9’s rio graphical user interface, including things like drawing a rectangle to open a new window. Rio is an acquired taste – to put it very mildly – and it seems MGR fits the same bill. There’s also $home movie, an entire video editor for MGR, which is honestly mind-blowing considering it’s running on a mere SPARCstation in the late ’80s and early ’90s. It has an incredibly unique UNIXy flavour:

If you don’t have 40 minutes to watch the tour, please do spend two minutes on this demo of the “$HOME MOVIE” system. It is “a suite of tools for the capture, editing and playback of window system sessions on a Sun Sparcstation” based on MGR. It is probably the most Unix way of making videos: the window manager dumps the rendering commands into a file, then the rendering commands can be altered with a set of small tools, some of which are in awk, and then these rendering commands can be packaged into a single demo.

↫ Nina Kalinina

Kalinina had to more or less reverse-engineer its unique video format, too, but in doing so managed to upload the original demonstration of $movie home, narrated by its creator and created in $movie home itself, to YouTube. Kalinina also created and uploaded a ready-made hard disk image of Debian 0.93 with Bellcore MGR preinstalled for use in Qemu and 86Box.

Have you ever heard of the Encore 91 computer system, developed and built by Encore Computer Corporation? I stumbled upon the name of this system on the website for the Macintosh like virtual window manager (MLVWM), an old X11 window manager designed to copy some of the look and feel of the classic Mac OS, and wanted to know more about it. An old website from what appears to be a reseller of the Encore 91 has a detailed description and sales pitch of the machine still online, and it’s a great read.

The hardware architecture of the Encore 91 series is based on the Motorola high-performance 88100 25MHz RISC processor. A basic system is a highly integrated fully symmetrical single board multiprocessor. The single board includes two or four 88100 processors with supporting cache memory, 16 megabytes of shared main memory, two synchronous SCSI ports, an Ethernet port, 4 asynchronous ports, real-time clocks, timers, interrupts and a VME-64 bus interface. The VME-64 bus provides full compatibility with VME plus enhancements for greater throughput. Shared main memory may be expanded to 272 megabytes (mb) by adding up to four expansion cards. The expansion memory boards have the same high-speed access characteristics as local memory.

↫ Encore computing 91 system

The Encore 91 ran a combination of AT&T’s system V.3.2 UNIX and Encore’s POSIX-compliant MicroMPX real-time kernel, and would be followed by machines with more powerful processors in the 88xxx series, as well as machines based on the Alpha architecture. The company also created and sold its own modified RISC architecture, RSX, for which there are still some details available online. Bits and bobs of the company were spun off and sold off, and I don’t think much of the original company is still around today.

Regardless, it’s an interesting system with an interesting history, but we’ll most likely never get to see oe in action – unless it turns up in some weird corner of the United States where the rare working examples of hardware like this invariably tends to end up.

After researching the first commercial transistor computer, the British Metrovick 950, Nina Kalinina wrote an emulator, simple assembler, and some additional “toys” (her word) so we can enjoy this machine today. First, what, exactly, is the Metrovick 950?

Metrovick 950, the first commercial transistor computer, is an early British computer, released in 1956. It is a direct descendant of the Manchester Baby (1948), the first electronic stored-program computer ever.

↫ Nina Kalinina

The Baby, formally known as Small-Scale Experimental Machine, was a foundation for the Manchester Mark I (1949). Mark I found commercial success as the Ferranti Mark I. A few years later, Manchester University built a variant of Mark I that used magnetic drum memory instead of Williams tubes and transistors instead of valves. This computer was called the Manchester Transistor Computer (1955). Engineers from Metropolitan-Vickers released a streamlined, somewhat simplified version of the Transistor Computer as Metrovick 950.

The emulator she developed is “only” compatible on a source code level, and emulates “the CPU, a teleprinter with a paper tape punch/reader, a magnetic tape storage device, and a plotter”, at 200-300 operations per second. It’s complete enough you can play Lunar Lander on it, because is a computer you can’t play games on really a computer?

Nina didn’t just create this emulator and its related components, but also wrote a ton of documentation to help you understand the machine and to get started. There’s an introduction to programming and using the Metrovick 950 emulator, additional notes on programming the emulator, and much more. She also posted a long thread on Fedi with a ton more details and background information, which is a great read, as well.

This is amazing work, and interesting not just to programmers interested in ancient computers, but also to historians and people who really put the retro in retrocomputing.

The 1980s saw a flurry of graphical user interfaces pop up, almost all of them in some way made by people who got to see the work done by Xerox. Today’s topic is no exception – GEM was developed by Lee Jay Lorenzen, who worked at Xerox and wished to create a cheaper, less resource-intensive alternative to the Xerox Star, which he got to do at DRI after leaving Xerox. His work was then shown off to Atari, who were interested in using it.

The entire situation was pretty hectic for a while: DRI’s graphics group worked on the PC version of GEM on MS-DOS; Atari developers were porting it to Apple Lisas running CP/M-68K; and Loveman was building GEMDOS. Against all odds, they succeeded. The operating system for Atari ST consisting of GEM running on top of GEMDOS was named TOS which simply meant “the operating system”, although many believed “T” actually stood for “Tramiel”.

Atari 520 ST, soon nicknamed “Jackintosh”, was introduced at the 1985 Consumer Electronics Show in Las Vegas and became an immediate hit. GEM ran smoothly on the powerful ST’s hardware, and there were no clones to worry about. Atari developed its branch of GEM independently of Digital Research until 1993, when the Atari ST line of computers was discontinued.

↫ Nemanja Trifunovic at Programming at the right level

Other than through articles like these and the occasional virtual machine, I have no experience with the various failed graphical user interfaces of the 1980s, since I was too young at the time. Even from the current day, though, it’s easy to see how all of them can be traced back directly to the work done at Xerox, and just how much we owe to the people working there at the time.

Now that the technology industry is as massive as it is, with the stakes being so high, it’s unlikely we’ll ever see a place like Xerox PARC ever again. Everything is secretive now, and if a line of research doesn’t obviously lead to massive short-term gains, it’s canned before it even starts. The golden age of wild, random computer research without a profit motive is clearly behind us, and that’s sad.

For an operating system that was once incredibly popular and expected to become a standard for a long time to come, it’s remarkable how little experience most people have with CP/M. In fact, many conventions and historical limitations you might be aware of – like the 8.3 filename convention of DOS – come straight from CP/M, as it influenced DOS considerably. It’s quite easy to emulate CP/M today, but it’s just old and different enough that getting into it might be a but confusing, but that’s where Eerie Linux’s introduction to CP/M comes into play.

This article is just what the headline promises: an introduction to the CP/M operating system. No previous knowledge of 1970s and early ’80s operating systems is required. However, some familiarity with Linux or a BSD-style operating system is assumed, as the setup process suggested here involves using a package manager and command-line tools. But why explore CP/M in the 2020s? There are (at least) two good reasons: 1) historical education 2) gaining a better understanding of how computers actually work.

↫ Eerie Linux

This article is a great way to get up and running with CP/M fairly quickly, and I intend to do just that when I find some time to mess around with it. What are some of the core, crucial applications that one should try on CP/M? Things people would be using back when CP/M was properly in use?