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.

Now read on…

ZX keyboard controller

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

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.

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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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