rob.rho.org.uk

I’ve been running a traditional Dungeons & Dragons game with my daughters¹. The fundamentals of table-top roleplaying haven’t changed very much since I was doing it at their age, but we came across one thing that definitely wasn’t available back then: HeroForge. It’s a website (we didn’t have those in the 80s) where you can create a 3D model of your character (would be a push on the Electron) and download a file for your 3D printer (we definitely didn’t have those in the 80s).

Imagine a character customiser from a game like Skyrim and you have the basic idea, but the thing that makes it is the breadth and quality of the execution. You could select a few basic attributes, costume items and equipment, but you can also customise every detail, including minutiae of pose and expression. Once you’re happy, you can buy the STL file for printing for about $8 (£6) — costly if you want to build an army², but for a few player characters it’s a very fair price for what you’re getting.

The girls each made a miniature of their character, and we’ve been pretty pleased with the 25mm scale ones for actual play. I printed these on the Bambu A1 with a 0.2mm nozzle; I’m sure I could get better detail with resin printing, but it’s pretty good and to be frank I’ve seen worse in commercially produced metal ones back in the day. Last week, they asked for bigger versions, so I printed them out at 400%. Worked a treat (after a bit of experimenting with supports), and really shows off the models.

Custom miniatures aren’t going to change the game that much, but they’re definitely add an extra point of enjoyment, and aren’t something I’d have even imagined being able to do forty years ago. Living in the future isn’t all bad.

In a recent post, I alluded to my “newly tricked-out Electron”, and promised more detail in a future post. This is that post, and pictured above is the Electron in question, with its new friend the Plus 1 Mini.

While of course dear to my heart, the Acorn Electron was never what you’d call a powerhouse. Its 32K of RAM wasn’t terrible on paper, but the lack of a true text mode meant that much of it was given over to the screen. Moreover, the base unit had limited connectivity, only video (RF, composite and RGB) and a cassette interface for mass storage. What there was was an expansion slot on the back of the machine that gave access to almost all of the internals, and this offered a way forward.

Due to the Electron’s limited success in the market, and the more general problems they were facing, Acorn only released two expansions (the multi-purpose Plus 1 — more on that below — and the Plus 3 disc drive). However, third parties such as Slogger and Cumana picked up the mantle, producing a wider range of peripherals and keeping the ecosystem going for a few years longer than it might have.

More recently, the retro community (such as the fine people on StarDot) have continued this tradition, and there are numerous more modern options that open up interesting possibilities. I’d been eyeing up various of these for a while, but was inspired to take the plunge by this post from Mark Moxon (who’s work on Elite is well worth checking out if you haven’t already).

The Plus 1 Mini, unlike some other options, doesn’t exactly ape the physical form of the Acorn Plus 1 — as you can see in the photo, it’s not quite as wide as the Electron itself — but is similar in spirit in that it offers a grab-bag of useful capabilities in a single package. There are the obvious and characteristic dual cartridge slots, and a joystick port (Atari-style, rather than analogue). Inside are headers to connect a Raspberry Pi Zero to emulate the Tube second processor interface, which is definitely something I want to try out in the future. However, there are two items in particular that make a night-and-day difference to the capability of the machine: 128K of sideways RAM, and an SD card slot.

What makes the RAM sideways is a whole topic in itself, but suffice to say that it’s not just more of the same. The 16-bit address bus means the 6502 can only reference a 64K address space, which needs to cover both RAM and ROM, including the OS. To make use of more than 64K, a fair amount of bank switching is required. Fortunately, Acorn MOS provides a well developed system for doing this. An added bonus is that the sideways RAM isn’t subject to the compromises the Electron makes to share the main RAM with video, and so access is twice as fast.

The biggest benefit, though, is the SD card slot, which essentially emulates a stack of floppy disks¹. Previously I’d been using the excellent PlayUEF to load cassette images, which allows you to pick from a vast library of software and load it with a great facsimile of my 1980s experience. However, I never figured out a good way to get the reverse process working, and thus never had a way to save work from the Electron. This severely limits the kind of experimentation you can do with the machine.

With the Plus 1 Mini, I can not only try out an even wider range of software (including ROM images, which can be loaded into sideways RAM), but can actually do things that last across multiple sessions. I’m excited to see what possibilities this opens up. I’ve already found that the expanded Electron is a significantly more capable (even useful) machine, and it seems clear that it could indeed have been the basis for a thriving ecosystem if history had gone a little differently.

I’ve just got round to uploading a quick model I made a few weeks ago: sleeves for reusable coffee cups. We have a couple of these basic cups in the car for when we get coffee on long journeys, but they can get a bit hot, and it’s not always clear whose drink is whose. Printing a couple of these in different colours makes them both easier to identify and more comfortable to hold. Not exactly earth-shattering, but a tiny quality of life improvement.

• Coffee cup sleeve on MakerWorld
• CoffeeCupSleeve.scad OpenSCAD file

I’m having an unexpectedly parentheses-heavy weekend. As well as experimenting with Acornsoft LISP on my newly-tricked-out Electron (more on that in a future post), I had a minor itch at work, and I decided to turn to Emacs to scratch it.

I wanted a quick tool to track what I’m working on, to get a clearer picture of where my time is going. Specifically, I wanted a list of tasks and time spent each day, in a form that I could collate and generate statistics from.

There are innumerable ways this could be done, and I have plenty of experience in quite a few of them. For something that’s just for personal use, a full application toolkit is almost certainly overkill. The last time I did this exercise I used Excel, which worked pretty well on the statistics side but left the entry of the data more manual than I wanted, so this time I wanted to try something else. I decided to return to an old staple.

Within about half an hour, I’d put together something serviceable — a new editing mode for an simple, ad hoc format that allowed me to quickly enter timestamped entries in a few keystrokes, while retaining all of Emacs’ more general editing facilities. Reading this into a Python notebook to analyse will be similarly easy when I get to it.

As mentioned, I could have done all of this in a more powerful and general application toolkit, but that would have probably taken longer than I could justify. The advantage of Emacs (and Excel, and a few other similar systems) is that they provide a rich structure to tweak to your specific needs. The interesting question is in the details; in this case, Emacs’ system of editable text buffers was a better fit that Excel’s grid of cells, but often the converse is true. It makes me wonder, are there other useful structures with similar properties? It’s a space that seems both fertile and under explored.

The Aerial screensaver has always been one of my favourite quality-of-life details of the Apple TV box, and I was happy to see it arrive on macOS, with the bonus touch of slowing and becoming the desktop background when you unlock the computer.

For a long while I stuck with the default Sequoia forest video, but recently I fancied a change, and opening up Settings I came across an absolute gem that I had no idea was there, the “Macintosh” screensaver.

This consists of extreme, animated close-ups of UI from the original 1984 Mac, slowly panning over a colour gradient background. Not only is the effect superbly executed, but the content is well chosen — recognisable applications such as MacPaint and MacWrite, the iconic cursive “hello”, and (slightly anachronistically) the “here’s to the crazy ones…” text.

I’m not entirely sure how this ended up in macOS. Apple are now a globe-spanning behemoth serving an incredibly broad customer base. Most of their customers weren’t born in 1984, and I’d imagine most of those who were wouldn’t recognise what they were seeing. The fact that something so niche made it through the big company machinery is surprising, and it delights me a little every time I open my computer.

Update 2025-07-18: This morning I noticed another nice touch; the time on the virtual Mac is correct, and updates live. I’d assumed it was basically a layered motion graphic, but apparently they’ve gone to even more effort than I thought. Brilliant.