Author: Jenny List

3309 Articles

Reading Data From A CD, With A Microscope

January 22, 2023 by 18 Comments

There was a time when electronic engineering students studied the audio CD, for all its real-world examples of error correction and control systems. There’s something to be found in the system still for young and old though, and thus we were intrigued when we saw [Peter Monta] reading the data from a CD using a microscope.

CDs encode data as so-called pits and lands in a spiral track across a metalised surface, with a transition from pit to land signifying a logic 1 and a missing transition signifying a 0. Reading a section of the raw data is achieved in the first part of his write-up, but in the next installment he goes further into retrieving more data through stitching together microscope pictures and writing some code to retrieve data frames. He’s not quite at the audio playback stage, but he’s planning in the future to spiral-track a full image to rip an entire disc.

There are plenty of CD drives around to read audio the conventional way, but the techniques here still find a use where less ubiquitous media has to be read. In the last decade for example there was an effort to read the BBC Domesday Project from the 1980s, as it became clear that few of the original readers survived in working order.

An Unexpected Amiga Network Interface

January 21, 2023 by 31 Comments

The retrocomputer enthusiast has increasingly to grapple with not only runaway computer prices but the astronomical cost of vintage peripherals. A welcome solution in some cases comes from the Raspberry Pi, which has proved itself fast enough to emulate those add-ons for a lot less outlay. A good one comes from [Niklas Ekström], who’s made a Pi-based network adapter for the Commodore Amiga 1200. Better still it doesn’t hog the main expansion port or the PCMCIA slot, instead it sits on the 1200’s rarely-used real-time-clock port. Software wise it uses an updated version of his earlier project for the Amiga 500. It provides access to the Pi command prompt, as well as a SANA driver and a mounted filesystem.

While many of us view the Amiga from 2023 as a retro gaming platform, for those of us who used it at the time it was a desktop productivity machine on a more affordable budget than the Macintosh. At the time the thought of having a UNIX-like operating system running on a super-powerful co-processor in your Amiga would have been beyond our wildest dreams, but whether it provides enough now to make a 1992 machine compete on the desktop is debatable. Who wants to run Firefox from the Pi in an X server on the Amiga?

Addressable LEDs From A Z80

January 19, 2023 by 3 Comments

If you buy WS2812s under the Adafruit NeoPixel brand, you’ll receive the advice that “An 8 MHz processor” is required to drive them. “Challenge Accepted!“, says [ShielaDixon], and proceeded to first drive a set from the 7.3 MHz Z80 in an RC2014 retrocomputer, and then repeat the feat from a 3.5 MHz Sinclair ZX Spectrum.

The demos in the videos below the break are all programmed in BASIC, but she quickly reveals that they call a Z80 assembler library which does all the heavy lifting. There’s no microcontroller behind the scenes, save for some glue logic for address decoding, the Z80 is doing all the work. They’re all implemented on a pair of RC2014 extension cards, a bus that has become something of a standard for this type of retrocomputer project.

So the ubiquitous LEDs can be addressed from some surprisingly low-powered silicon, showing that while it might be long in the tooth the Z80 can still do things alongside the new kids. For those of us who had the Sinclair machines back in the day it’s particularly pleasing to see boundaries still being pushed at, as for example in when a Z80 was (almost) persuaded to have a protected mode.

Continue reading “Addressable LEDs From A Z80” →

The First Afghan Sports Car Has An Engine You Shouldn’t Mock

January 17, 2023 by 125 Comments

In the news today, Afghanistan has made its first sports car, and it’s a sleek and low-slung model with a throaty exhaust note that would get a second look on the Autobahn just as much as it does on the streets of Kabul. Making a modern sports car is an impressive achievement no matter where you do it, but it wouldn’t be something we’d share with you were it not for how the story is being reported. The general tone of Western reporting is focused not upon the car itself, but instead poking fun of it for using a Toyota engine also found in a Corolla.

Anyone who grew up during the Cold War will remember the rhetoric of the era with respect to technology. To paraphrase a little, our planes or rockets were based on the finest and latest high technology, we were told, while theirs were held together with string and sealing wax from the 1940s. This neglected the fairly obvious fact that Soviet probes were visiting all the planets, something they must have had some pretty good tech at their disposal to achieve. This was then explained as the product of their having stolen all our super-advanced Western tech, something we now know that our lot weren’t averse to either when the opportunity arose.

It’s this which is brought to mind by the mirth of the Western commentators at the Afghan car’s supposedly humble engine. It doesn’t matter what you think of the Afghan regime (and there’s plenty there to criticize), the car should be assessed on its merits. After all, it’s hardly as though the engine in question didn’t find its way into more than one sports car that Western commentators might find appealing.

A Flex Sensor For A Glove Controller Using An LDR

January 15, 2023 by 14 Comments

When most of us think of glove controllers, the first which comes to mind is Nintendo’s PowerGlove, which promised much more than it delivered. But the idea persists, and from time to time we see them here at Hackaday. [Gord Payne] has one with an elegant sensor solution, it detects finger movement using a light dependent resistor.

The cleverest designs are those which are the simplest, and this one eschews complex mechanisms and exotic parts for a simple piece of flexible tube. At one end is an LED and at the other the LDR, and when attached to a glove it provides a finger sensor without the fuss. The amount of light reaching the LDR from the LED decreases as the pipe is bent, and with a simple divider circuit a voltage can be read by an Arduino. You can see it in action in the video below the break, where the glove flexing controls a servo.

Perhaps this might revitalize a bit of interest in glove controllers, something we probably don’t see too many of. Those Nintendo PowerGloves do still crop up from time to time though.

Continue reading “A Flex Sensor For A Glove Controller Using An LDR” →

Art of 3D printer in the middle of printing a Hackaday Jolly Wrencher logo

3D Printering: Can You Ever Have Enough Vitamins?

January 12, 2023 by 66 Comments

As a community we owe perhaps more than we realise to the RepRap project. From it we get not only a set of open-source printer designs, but that 3D printing at our level has never become dominated by proprietary manufacturers in the way that for example paper printing is. The idea of a printer that can reproduce itself has never quite been fully realised though, because of what the RepRap community refer to as “vitamins“.

These are the mass-produced parts such as nuts, bolts, screws, and other parts which a RepRap printer can’t (yet) create for itself. It’s become a convenience among some of my friends to use this term in general for small pieces of hardware, which leads me to last week. I had a freshly printed prototype of one of my projects, and my hackerspace lacked the tiny self-tapping screws necessary for me to assemble it. Where oh where, was my plaintive cry, are the vitamins!

So my hackerspace is long on woodscrews for some reason, and short on machine screws and self-tappers. And threaded inserts for that matter, but for some reason it’s got a kit of springs. I’m going to have to make an AliExpress order to fix this, so the maybe I need you lot to help me. Just what vitamins does a a lone hardware hacker or a hackerspace need? Continue reading “3D Printering: Can You Ever Have Enough Vitamins?” →

Virgin Not-Quite-Orbit-Yet

January 10, 2023 by 27 Comments

A country’s first orbital satellite launch from home soil is a proud moment, even when as is the case with Virgin Orbit, it’s not from the soil itself but from a Boeing 747 in the stratosphere over the sea. The first launch of the under-wing rocket took place yesterday evening, and pretty much every British space enthusiast gathered round the stream to watch history being made somewhere over the Atlantic south of Ireland. Sadly for all of us, though the launch itself went well and the rocket reached space, it suffered an anomaly in its second stage and failed to reach orbit.

No doubt we will hear more over the coming days as we’re sure they have a ton of telemetry data to work through before they find a definitive answer as to what happened. Meanwhile it’s worth remembering that the first launch of a new platform is a test of a hugely complex set of systems, and this one is certainly not the first to experience problems. It’s the under-wing launch that’s the interesting bit here, and in that we’re glad to see that part of the mission as a success. We know there will be a secomd launch and then many more, as not just the UK’s but Europe’s first launch platform from native soil becomes a viable and hopefully lower-cost launch option than its competitors.

People with very long memories will remember that this wasn’t the first time a British satellite launch attempt failed at the second stage and then went on to launch successfully, but Black Arrow launched Prospero back in 1971 from the Australian outback rather than the chilly North Atlantic.

Header: Österreichisches Weltraum Forum, CC BY-SA 4.0.