Indiegogo Calls Time On The ZX Vega

June 7, 2018 by Jenny List 15 Comments

It has been an exciting time to be a retro computer enthusiast in recent years, and the availability of affordable single board computers, systems-on-chip, and FPGAs have meant that retro hardware could be accurately reproduced or emulated. A host of classic micros have been reborn, to delight both the veterans who had the originals, and a new crop of devotees.

Today we have news of the impending demise of one of the higher-profile projects. The ZX Vega+ is a handheld Sinclair Spectrum console bearing the Sinclair name that came with an impeccable pedigree in that it had the support of the man himself. It seemed like a good proposition on the crowdfunding site Indiegogo, and when it made its debut there in early 2016 it attracted over half a million pounds worth of backing in short order. Things soon went sour though, with reports of a falling-out within Retro Computers, followed by multiple missed deadlines and promises undelivered over the last couple of years. With little sign of either the money or the console itself, it seems Indiegogo have now lost patience and will be sending in the debt collectors to recover what they can. Whether the backers will see any of their money is unclear.

It’s fair to say that the ZX Vega saga has been a tortuous and rather sordid one, out of which few players emerge smelling of roses. In a way though it is entirely in keeping with the spirit of the 8-bit era, as the period from the late 1970s onwards was littered with the financially bare corpses of dubiously run companies in the home computer industry. Meanwhile if you are hankering for a Vega it should be easy enough to create one for yourself, as Retro Computers Ltd admitted that under its skin was a copy of the FUSE software emulator. We suspect that most Hackaday readers could take a Raspberry Pi and a suitable LCD, pair them with a 3D-printed case and an 18650 cell, and be playing Manic Miner in no time. Far simpler than this convoluted Spectrum project!

It’s UNIX. On A Microcontroller.

June 3, 2018 by Jenny List 70 Comments

It’s difficult to convey in an era when a UNIX-like operating system sits in your pocket, how there was once a time when the mere word was enough to convey an aura of immense computing power. If you ran UNIX, your computer probably filled a room, and you used it for Serious Stuff rather than just checking your Twitter feed. UNIX machines may still perform high-end tasks, but Moore’s Law has in the intervening years delivered upon its promise, and your phone with its UNIX-like OS is far more powerful than that room-sized minicomputer of the 1970s. A single chip for a few cents can do that job, which begs the question: just how little do we need to run UNIX today? It’s something [Joerg Wolfram] could advise you upon, because he’s got a functional UNIX running on a microcontroller.

Of course, the UNIX in question is not exactly the same as the one you’d find on a supercomputer, either in the 1970s or now. Mini UNIX is a minimalist version of the operating system developed by [Heinz Lycklama] at Bell Labs four decades ago. It gives you a complete UNIX V6 system for the DEC PDP-11, but which needs only 56K of RAM, and no MMU. Emulating a PDP-11 on an STM32 microcontroller allows it to run happily, and while it’s not the most minimalist of microcontrollers it’s still a pretty cheap part upon which to run UNIX.

It’s doubtful whether a 1970s version of an operating system on a commodity microcontroller will take the world by storm, but that’s hardly the point of such a neat hack. It’s certainly not the first time we’ve seen similar work, though this PIC32 offering has a little more in the way of resources to offer.

Header image: Golonlutoj [CC BY-SA 3.0].

Bringing Back A Spectrum’s Rails

June 2, 2018 by Jenny List 10 Comments

The Sinclair ZX Spectrum was to most Brits the computer to own in the early 1980s, it might not have had all the hardware features of its more expensive competitors but it had the software library that they lacked. Games came out for the Spectrum first, and then other platforms got them later. If you didn’t have a rubber keyboard and a Sinclair logo, you were nothing in the playground circa 1984. That low price though meant that in true Sinclair tradition a number of corners had been cut in the little micro’s design. Most notably in its power supply, all the various rails required by the memory chips came from a rather insubstantial single-transistor oscillator that is probably the most common point of failure for these classic machines.

[Tynemouth Software] had an Issue 2 Spectrum with a missing -5V rail, and has detailed both the power supply circuit used on these machines and the process of faultfinding and repairing this one. A single transistor oscillator drives a little ferrite-spool transformer from which the various supplies are rectified and filtered. Similar circuits appear in multiple generations of Sinclair hardware, where we might nowadays use a little switching regulator chip.

We’re taken through the various stages of faultfinding this particular circuit, and the culprit is found to be a faulty Zener diode. It’s certainly not the last dead Spectrum that will cross an enthusiast’s bench, but at least in this case, the fault was less obtuse than they sometimes can be in this much-loved but sometimes frustrating machine.

Sinclair enthusiasts might also appreciate the great man’s earliest work.

Raspberry Pi’s Power Over Ethernet Hardware Sparks False Spying Hubbub

June 1, 2018 by Jenny List 86 Comments

Have you ever torn open an Ethernet jack? We’d bet the vast majority of readers — even the ones elbow-deep into the hardware world — will answer no. So we applaud the effort in this one, but the conclusion landed way off the mark.

In the last few days, a Tweet showing a Raspberry Pi with its Ethernet socket broken open suggested the little PCB inside it is a hidden bug. With more going on inside than one might expect, the conclusion of the person doing the teardown was that the Raspberry Pi foundation are spying upon us through our Ethernet traffic. That’s just not the case. But we’re still excited about what was found.

Continue reading “Raspberry Pi’s Power Over Ethernet Hardware Sparks False Spying Hubbub” →

Laser-Powered Flying Machine Weighs Milligrams

May 30, 2018 by Jenny List 21 Comments

We’ve become used to seeing some beautiful hand-made creations at the smaller end of the flying machine scale, tiny aircraft both fixed and rotary wing. An aircraft that weighs a few grams is entirely possible to build, such have been the incredible advances in component availability.

But how much smaller can a working aircraft be made? Given a suitable team and budget, how about into the milligrams? [Dr. Sawyer Fuller] and his team at the University of Washington have made an ornithopter which may be the lightest aircraft yet made, using a piezoelectric drive to flap flexible wings. That in itself isn’t entirely new, but whereas previous efforts had relied on a tether wire supplying electricity, the latest creation flies autonomously with its power supplied by laser to an on-board miniature solar cell that protrudes above the craft on its wires.

Frustratingly Dr. Fuller’s page on the machine is lighter on detail than we’d like, probably because they are saving the juicy stuff for a big reveal at a conference presentation. It is however an extremely interesting development from a technical perspective, as well as opening up an entirely new front in the applications for flying machines. Whatever happens, we’ll keep you posted.

You can see the craft in the video below the break, and if you’re interested lies with more conventional tiny machines take a look at the creator of a 2.9g Mustang model.

Continue reading “Laser-Powered Flying Machine Weighs Milligrams” →

A Li-Ion Booster Pack, Done Right

May 27, 2018 by Jenny List 12 Comments

We’re all used to battery booster packs containing a Li-ion or Li-poly cell and a little inverter circuit, they are a standard part of 21st century daily survival for those moments when smartphone battery lives don’t perform as advertised. But how many of us have considered what goes into them, and further how many of us have sought to produce the best one possible rather than a unit built at the lowest price?

It’s a course [Peter6960] has followed, producing a PCB that sits on the back of an 18650 cell holder. It follows the work of [GreatScott] in particular in its use of the TP4056 charger, MT3608 boost converter, and FS312F protection ICs. Many commercial modules omit any protection circuit, and the FS312F is of particular interest because it has a low 2.9V cut-off voltage that should lengthen the life of the cell. Files for the PCB can be found in a zip file hosted on Google Drive.

You might think that there was nothing new that could be learned about a Li-ion battery booster, but it’s always worth a look at a well-executed piece of work. We noticed he refers to Li-poly cells while using what appears to be a Li-ion 18650 cell. Most likely this is merely an oversight.

There is a lot to know about the characteristics and safety of the lithium-chemistry rechargeables, you may find [Sean Boyce]’s article on the subject to be an interesting read.

A Classy SDR Chip, Decapped

May 27, 2018 by Jenny List 20 Comments

If you are a regular searcher for exotic parts among the virtual pages of semiconductor supplies catalogs, you will have probably noticed that for a given function it is most often the part bearing the Analog Devices logo that is the most interesting. It may have more functionality, perhaps it will be of a higher specification, and it will certainly have a much higher price. [Zeptobars] has decapped and analyzed an AD chip that holds all three of those honors, the AD9361 SDR transceiver.

It’s placed under a slightly inflammatory title, “when microchips are more profitable than drugs“, but does make a good job of answering why a semiconductor device at the very cutting edge of what is possible at the time of release can be so expensive. The AD9361 is an all-in-one SDR transceiver with an astonishing bandwidth, and as such was a particularly special device when it reached the market in 2013. We see some particularly fine examples of on-chip inductors and PLL circuitry that must have consumed a significant design effort to preserve both bandwidth and noise characteristics. This is an item of physical beauty at a microscopic scale as well as one of technical achievement.

The financial analysis puts Analog Devices’s gross profit at about $103 of the $275 retail purchase price of an AD9361. The biggest slice at $105 goes to the distributor, and surprisingly the R&D and manufacturing costs are not as large as you might expect. How accurate these figures are is anybody’s guess, but they are derived from an R&D figure in the published financial report, so there is some credence to be given to them.

We’ve featured [Zeptobar’s] work before more than once. A look at fake Nordic Semi parts for example or a Soviet i8080 clone have received their treatment. Always a source to watch out for!