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Submission + - A Dog Symphony helps you understand Direct Digital Synthesis (

szczys writes: Direct Digital Synthesis is a method of generating audio from stored values. It's the basis of digital audio playback and learning to implement it on a microcontroller will give you a great understanding of audio generation and manipulation. But the topic can be a bit dry. That's why Elliot Williams chose to create a barking dog symphony as the vehicle for his DDS explanation. Using one sample, and an 8-bit microcontroller, he walks through issues like combining playback of multiple voices at one time, and how to reconcile a changing sample rate with a fixed clock rate.

Submission + - The Internet of Broken Things (

szczys writes: The Internet of Things is all the hype these days. On one side we have companies clamoring to sell you Internet-Connected-everything to replace all of the stuff you already have that is now considered "dumb". On the other side are security researchers screaming that we're installing remote access with little thought about securing it properly. The truth is a little of both is happening, and that this isn't a new thing. It's been around for years in industry, the new part is that it's much wider spread and much closer to your life. Al Williams walks through some real examples of the unintended consequences of IoT, including his experiences building and deploying devices, and some recent IoT gaffs like the NEST firmware upgrade that had some users waking up to an icy-cold home.

Submission + - Grandma's Phone, DSL, and the Copper They Share (

szczys writes: DSL is high-speed Internet that uses the same twisted pair of copper wire that still works with your Grandmother's wall-mounted telephone. How is that possible? The short answer is that the telephone company is cheating. But the long answer delves into the work of Claude Shannon, who figured out how much data could be reliably transferred using a given medium. His work, combined with that of Harry Nyquist and Ralph Hartley (pioneers of channel capacity and the role noise plays in these systems), brings the Internet Age to many homes on an infrastructure that has been in use for more than a hundred years.

Submission + - The Hydrillium Accident that Made Rock-afire Explosion an Ironic Band Name (

szczys writes: One fine September morning an explosion rocked the city of Orlando. An inventor had been experimenting with production, transport, and adoption of Hydrillium as an energy storage medium. The gas is produced by arcing electricity across carbon rods submerged in water. Hydrillium hasn't been widely adopted because of its low energy density by volume but Aaron Fechter sought to change that by storing the gas at high pressure. The storage tank eventually failed due to Stress Corrosion Cracking and Hydrogen Embrittlement; taking out a wall and the roof with a pressure wave when it gave out. There wasn't a fireball, the flammable gas dispersed without further incident and without casualties. But knowing that Aaron was the creator of The Rock-afire Explosion — a robot band found in the pizza parlors of your youth — you have to ask, isn't it ironic?

Submission + - One Hoss Shay and Our Society of Obsolescence (

szczys writes: The last time you replaced your smart phone, was the entire thing shot or had just one part gone bad? Pretty much every time it's one thing; the screen has cracked, or the WiFi stopped working predictably. But the other parts of the phone were fine. The same is true for laptops, or cars, or one-horse carriages. In fact this is a concept that has been recognized for well over one hundred years. The stuff we buy isn't meant to last forever, otherwise we wouldn't buy more of them. And for that matter, nothing lasts forever despite design. But what if everything was optimized to fail all at once? Instead of a single point of weakness, all parts wore equally and failed in the same time frame. Finding a balance between the One Hoss Shay model, and encouraging the return of user-serviceable parts would go a long way toward making sure that replacement is a choice and not a necessity.

Submission + - VGA in Memoriam ( 1

szczys writes: VGA is going away. It has been for a long time but the final nails in the coffin are being driven home this year. It was the first standard for video, and is by far the longest-lived port on the PC. The extra pins made computers monitor-aware; allowing data about the screen type and resolution to be queried whenever a display was connected. But the connector is big and looks antiquated. There's no place for it in today's thin, design minded devices. It is also a mechanism for analog signaling in our world that has embraced high-speed digital for ever increasing pixels and integration of more data passing through one connection. Most motherboards no longer have the connector, and Intel's new Skylake processors have removed native VGA functionality. Even online retailers have stopped including it as a filter option when choosing hardware.

Submission + - The Dark Arts: Meet the LulzSec Hackers (

szczys writes: Reputations are earned. When a small group of hackers who were part of Anonymous learned they were being targeted for doxing (having their identities exposed) they went after the person hard, taking down two of the company websites, the CEO's Facebook, Twitter, Yahoo, and even his World of Warcraft accounts. The process was fast, professional, and like nothing ever seen before. This was the foundation of Lulz Security and the birth of a reputation that makes LulzSec an important part of black hat history.

Submission + - Overunity, Free Energy, Perpetual Motion to the Modern Mad Scientist (

szczys writes: Making change for $1.00 and getting $1.10 back. That's the premise of overunity, free energy, and perpetual motion experiments. Using money as the the analogy is fitting because these concepts are heavily aligned with scams trying to land a payday for their "research". But there is another branch of people working on them: tinkerers who believe they can actually solve the problem. Laws of thermodynamics say otherwise, but this isn't necessarily wasted time. Other breakthroughs are waiting to be discovered as these mad scientists try to remove all efficiency losses from their doomed systems. They are one place to look for interesting ideas on low-friction, high efficiency fabrication.

Submission + - The Trouble with Intel's Management Engine (

szczys writes: You've used many devices that have Intel's Management Engine built into them, even if you haven't heard of it before. This is the lowest level of security, built directly into the chips. But obscurity is part of its security and part of its weakness. Nobody knows exactly how ME works, yet it includes a wide range of features that would be frightening if exploited. The ME is always listening, able to receive packets even when the device is asleep. And it has the lowest level of access to every part of the computer system.

Submission + - Hunting Malware with GPUs and FPGAs (

szczys writes: Rick Wesson has been working on a solution to identify the same piece of malware that has been altered through polymorphism (a common method of escaping detection). While the bits are scrambled from one example to the next, he has found that using a space filling curve makes it easy to cluster together polymorphically similar malware samples. Forming the fingerprint using these curves is computationally expensive. This is an Internet-scale problem which means he currently needs to inspect 300,000 new samples a day. Switching to a GPU to do the calculation proved four orders of magnitude efficiency over CPUs to reach about 200,000 samples a day. Rick has begun testing FPGA processing, aiming at a goal of processing 10 million samples in four hours using a machine drawing 4000 Watts.

Submission + - What's in a Tool? A Case for Made in the USA (

szczys writes: You have the choice of buying a wrench made in the USA and one made in China. Which one should you buy? The question is not a straightforward one. Tools are judged by their ability to do the job repeatedly and without fail. To achieve this, only the best of design and manufacturing will do. But this is a high bar when you factor in price competition which often leads to outsourcing production. Gerrit Coetzee looks at this issue, comparing two instances of the same model of Crescent brand adjustable wrench; one a legacy manufactured in the USA, another outsourced for manufacture in China.

Submission + - Stallman's Legacy Halts at Hardware (

szczys writes: To say Richard Stallman had a profound effect on Open Source Software is not a bold enough statement. The power of the GPL, and his advocacy for software freedom have changed the world. But there is one frontier that has yet to hear this gospel. These days, no Hardware is an island. Almost every type of electronics we use is running some type of code, and in almost every case some of that code is secret in more ways than one. From beefy processors, to graphics controllers, boot ROMs and binary blobs run in the silicon we base our systems upon. The code is not published and in the rare case that you are able to view the source it is only under strict NDA. This represents one of the biggest barriers to true Open Hardware.

Submission + - The Hardware that Searches for Dark Matter (

szczys writes: Deep in a gold mine in South Dakota the Large Underground Xenon experiment waits in the darkness for a tiny flash of light that signals that dark matter actually exists. So far we theorize that it does exist, and have gone to great lengths to build hardware to detect dark matter. Very cold, very pure liquid Xenon sits waiting for a dark matter particle to strike the nucleus of a Xenon molecule, producing a distinct pattern of photons through scintillation. An array of photomultiplier tubes detect the photons, whose pattern is processed by FPGAs on custom boards connected using HDMI. The experiment has generated a list of properties not possessed by dark matter; running for several years no evidence of the particles interacting with the Xenon have been found. But when the data collection concludes this year, a much larger version of the impressive hardware will be built.

Submission + - Hackers and Heroes: A Tale of Two Countries (

szczys writes: "Hackers" — people who non-maliciously test the limits of technology — have a very different societal standing depending on the country they live in. To illustrate the concept, consider the history of hackers in the United States versus those in Germany. Both communities have their genesis with the telecom systems of the 1980's, when hackers were called Phone Phreakers and traded secrets on telephone system exploits. These groups were the earliest to test the security and vulnerability of the burgeoning Internet, but their paths diverged. Hackers in Germany formed political parties while in the US they were targeted by law enforcement. The result is two very different communities filled with highly skilled individuals, but one must fly under the radar while the other enjoys much wider open acceptance.

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Just about every computer on the market today runs Unix, except the Mac (and nobody cares about it). -- Bill Joy 6/21/85