The Sinclair ZX81: a Raspberry Pi retro restyle – Part 2

Previously on ‘ZX81: a Raspberry Pi retro restyle’: I used a headerless Arduino Leonardo to connect a ZX81 microcomputer keyboard to a Raspberry Pi via USB, using code to handle normal, shifted and function-shifted key presses.

After some searching on eBay, I found an old ZX81 going cheap because it lacked cables, though when it arrived, I found the computer itself to be in excellent condition. Possibly it has never been used, though how if that were the case the cables were lost and the box got so tatty is a mystery I will probably never solve.

ZX keyboard controller

A new ZX keyboard connected to the USB controller – an Arduino Leonardo

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The Sinclair ZX81: a Raspberry Pi retro restyle – Part 1

I love the design of the Sinclair ZX81. It was never a great computer, even in 1981. It only had 1KB of on-board RAM, it was slow, it was small, it could only do black and white graphics, and it’s membrane keyboard was useless for fast typing. But it looked fantastic: black, sleek and totally futuristic. Almost all other 1980s microcomputers now look very dated. No surprise there, of course, but the ZX81 still looks amazing.

Hats off to Sinclair Research’s industrial designer, Rick Dickinson, for devising a design that is genuinely timeless.

The ZX81 membrane keyboard

The ZX81 keyboard hooked up to the Pi via USB and Arduino

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Retro Review: Thorn EMI Liberator (1985)

In November 2012, I wrote and published the definitive history of the Thorn EMI Liberator, the first British laptop computer, over at The Register. I’d never even heard of the machine when I first saw a picture of it. I spotted the snap while researching the story of the Dragon 32 – some of the Dragon engineers went on to develop the Liberator after Dragon Data, by then a subsidiary of electrical industry giant GEC, was closed down.

I talked to the Liberator’s hardware and software engineers, their bosses and to Bernard Terry, the former civil servant who had the idea for a portable device for text processing in the first place. I even got to see a real Liberator, courtesy of the Science Museum in London, which has one in its collection, though not on public display. That’s a shame, given the Liberator is an example of pioneering British technology. More to the point, I wasn’t able to turn it on and try it out.

Thorn EMI Liberator

The Liberator in action

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RIP: Dragon 32 (1982-2013) my first 8-bit colour microcomputer

My Dragon 32 – bought from Boots, Central Milton Keynes by my father for my Christmas 1982 present – passed away this weekend during routine maintenance. It was 31.

Its early life was a very active one. It help me hone my knowledge of Basic programming, and it soon became my platform for learning the assembly language and machine code of the Motorola 6809E processor, on which it was based. Some of my earliest published work were program listings written on my Dragon and submitted to Britain’s home computer magazines of the early 1980s.

Dragon 32, at peace now

Dragon 32, at peace now

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