Saturday, 30 January 2021

Computers I Have Known - Part One

In the spirit of very entertaining blog posts by Jacques Mattheij and Jim Lawless, I thought I might celebrate having written computer software professionally for 20 years, by recapping all the computers I have known, since the beginning.

And in the beginning, there was, an Acorn Electron. Yes, the "King of the 8-Bits" BBC Micro's little brother, and, well, he wasn't very good. In their efforts to reduce the Beeb's chip count and cut costs to a Sinclair Spectrum-rivalling price-point, Acorn bottlenecked the processor's access to memory so that while for the most part it was compatible with BBC BASIC, programs would run, at best, around half the speed of the Model B.

8-year-old me neither knew nor cared about this however; I had a computer, in my bedroom, and it was amazing. I'm pretty sure my Dad picked the computer up from Curry's or Dixons (UK high street electrical retailers) at a heavily discounted price, just in time for my birthday. As he is a complete luddite I'm fairly sure he was advised by a family friend (a teacher) that the BBC Micro (or indeed, something compatible) would be a fine choice; I don't recall ever outwardly expressing a desire for a home computer but had certainly enjoyed playing the BBC B at our friends' house. That machine was very well specced with a disc drive and dedicated colour monitor; my setup was substantially lower-rent with a domestic-grade cassette recorder and a monochrome television pressed into service for display duties. Sadly I don't have a picture of my first "workstation" but here are some very close approximations:
The cassette recorder here is almost identical to what I had, in the same position to the left of the Electron, because that's where the I/O and motor control connectors were and the cable wouldn't reach anywhere else.
Here's the mighty Binatone 12-inch monochrome TV that was my "monitor". I was very pleased to be able to recall that brand name! It plugged into the Electron's RF port and had to be tuned in for a nice sharp picture. Although pretty crappy by almost every measure, I was at least lucky enough to have this TV dedicated for my computing, and so didn't have to share the family TV.

Together with the hardware came a veritable mountain of boxed software; almost all of it from Acornsoft in their distinctively-80s graph-squares-and-neon-script style:
(from acornelectron.co.uk)

These were a couple of my favourites; Starship Command was a very Star Trek-inspired shoot-em-up with lovely smooth circular scrolling and "high" resolution graphics (in black-and-white, the cost of such a resolution), while Sphinx Adventure was an impenetrable (well, it seemed like it) text adventure in the GO NORTH, TAKE SHOVEL, GO EAST, USE SHOVEL style.

Yep, games. Sorry, I'd love to be able to say I was busting out 6502 assembly and "racing the beam", unlocking hidden hardware capabilities and pushing the limits ... but no, while I did program, it was mostly small BASIC experiments based on these two books (that came in the original bundle):
Although I stayed very much "within the lines" of what those books showed me, I still built up the fundamentals of programming; variables, conditionals, looping. I never got as far as arrays on the Electron as far as I can tell - I remember wanting to make a virtual airport departures board (after being suitably impressed by the board at Gatwick Airport I think) and being stumped at how to make the departures "move up" as the topmost flight disappeared.

The main aspect of BBC BASIC I remember being fascinated with was the graphics "API", principally the LINE command, which would draw a straight line between two X,Y points in the current paint colour. Combined with a pair of nested loops, I'd build spider-web like meshes around the edges of the screen. Very, very slowly. The super-smooth inner curves thus achieved delighted me then, and indeed still do:
(Go chortle at my Codesandbox HTML Canvas version here)

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