Changing System Architectures And The Complexities Of Apple’s Butterfly Approach To ISAs

July 13, 2020 by Maya Posch 64 Comments

Apple computers will be moving away from Intel chips to its own ARM-based design. An interesting thing about Apple as a company is that it has never felt the need to tie itself to a particular system architecture or ISA. Whereas a company like Microsoft mostly tied its fortunes to Intel’s x86 architecture, and IBM, Sun, HP and other giants preferred vertical integration, Apple is currently moving towards its fifth system architecture for its computers since the company was formed.

What makes this latest change possibly unique, however, is that instead of Apple relying on an external supplier for CPUs and peripheral ICs, they are now targeting a vertical integration approach. Although the ARM ISA is licensed to Apple by Arm Holdings, the ‘Apple Silicon’ design that is used in Apple’s ARM processors is their own, produced by Apple’s own engineers and produced by foundries at the behest of Apple.

In this article I would like to take a look back at Apple’s architectural decisions over the decades and how they made Apple’s move towards vertical integration practically a certainty.

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How Early Radio Receivers Worked

July 10, 2020 by Al Williams 43 Comments

If you’ve ever built a crystal radio, there’s something magical about being able to pull voices and music from far away out of thin air. If you haven’t built one, maybe you should while there’s still something on the AM band. Of course, nowadays the equivalent might be an SDR. But barring a computer solution, there are not many ways to convert radio waves into intelligence. From a pocket radio to advanced RADAR to a satellite in orbit, receiving a radio wave is accomplished in pretty much the same way.

There are, however, many ways to modulate and demodulate that radio wave. Of course, an AM radio works differently than an FM radio. A satellite data downlink works differently, too. But the process of capturing the radio wave from the air and getting them into a form ready for further processing hasn’t changed much over the years.

In this article, I’ll talk about the most common radio receiver architectures you may have seen in years past, and next week I’ll talk about modern architectures. Either way, understanding receiver architectures will help you design new radios or troubleshoot them.

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Bridge Over Trebled Water: How The Golden Gate Bridge Started To Sing

July 8, 2020 by Alex Weinberg 28 Comments

Throughout the spring, some Bay Area residents from Marin County to the Presidio noticed a sustained, unplaceable high-pitched tone. In early June, the sound reached a new peak volume, and recordings of the eerie noise spread across Twitter and Facebook. Soon after, The Golden Gate Bridge, Highway, & Transportation District, the agency responsible for the iconic suspension bridge’s maintenance, solved the mystery: The sound was due to high winds blowing through the slats of the bridge’s newly-installed sidewalk railing. Though a more specific explanation was not provided, the sound is most likely an Aeolian tone, a noise produced when wind blows over a sharp edge, resulting in tiny harmonic vortices in the air.

The modification of the Golden Gate Bridge railing is the most recent and most audible element of a multi-phase retrofit that has been underway since 1997. Following the magnitude 6.9 Loma Prieta Earthquake in 1989, The Golden Gate Bridge, Highway, & Transportation District (The District) began to prepare the iconic bridge for the wind and earthquake loads that it may encounter in its hopefully long life. Though the bridge had already withstood the beating of the Bay’s strong easterly winds and had been rattled by minor earthquakes, new analysis technology and construction methods could help the span hold strong against any future lateral loading. The first and second phases of the retrofit targeted the Marin Viaduct (the bridge’s north approach) and the Fort Point Arch respectively. The third and current phase addresses the main span.

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Marian Croak Is The MVP Of VoIP Adoption

July 7, 2020 by Kristina Panos 23 Comments

If you’ve ever used FaceTime, Skype, own a Magic Jack, or have donated money after a disaster by sending a text message, then you have Marian Croak to thank. Her leadership and forward thinking changed how Ma Bell used its reach and made all of these things possible.

Marian Croak is a soft-spoken woman and a self-described non-talker, but her actions spoke loudly in support of Internet Protocol (IP) as the future of communication. Humans are always looking for the next best communication medium, the fastest path to understanding each other clearly. We are still making phone calls today, but voice has been joined by text and video as the next best thing to being there. All of it is riding on a versatile network strongly rooted in Marian’s work.

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The WIMP Is Dead, Long Live The Solar Axion!

July 6, 2020 by Moritz v. Sivers 23 Comments

For decades scientists have been building detectors deep underground to search for dark matter. Now one of these experiments, the XENON1T detector, has found an unexpected signal in their data. Although the signal does not stem from dark matter it may still revolutionize physics.

Since the 1980s the majority of scientists believe that the most likely explanation for the missing mass problem is some yet undiscovered Weakly Interacting Massive Particle (WIMP). They also figured that if you build a large and sensitive enough detector we should be able to catch these particles which are constantly streaming through Earth. So since the early 1990s, we have been putting detectors made from ultrapure materials in tunnels and mines where they are shielded from cosmic radiation and natural radioactivity.

Over the decades these detectors have increased their sensitivity by a factor of about 10 million due to ever more sophisticated techniques of shielding and discriminating against before mentioned backgrounds. So far they haven’t found dark matter, but that doesn’t mean the high-end sensing installations will go unused.

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The ISS Is Getting A New WC

July 1, 2020 by Kristina Panos 32 Comments

Every home needs renovations after a few decades, and the International Space Station is no different. This fall, they’ll be getting a new Universal Waste Management System (UWMS), aka a new toilet.

Though the news coincides with increased traffic to the ISS, this move stems from a more serious issue with bacterial contamination during longer-term space travel. Today’s ISS toilets already recycle urine back into potable water and scrub the air reclaimed from solid waste as it gets compacted and stored. The new UWMS will act more like a food dehydrator, reducing the water content as much as possible to save on space, and petrifying the poo to inactivate the bacteria.

The current commode on the American side of the ISS was designed in the 1990s and is based on the Space Shuttle’s facilities. It has a funnel with a hose for urine and a bag-lined canister with a seat for solid waste, both of which are heavily vacuum-assisted.

Though the current toilet still does everything it’s supposed to do, there is room for improvement. For instance, women find it difficult to engage both parts of the system at the same time, and almost everyone prefers the toe bars on the Russian toilet to the more encumbering thigh bars on the American throne. Also, the current commode’s interface is more complicated than it needs to be, which takes up valuable crew time. Continue reading “The ISS Is Getting A New WC” →

USB-C Is Taking Over… When, Exactly?

June 23, 2020 by Lewin Day 182 Comments

USB is one of the most beloved computer interfaces of all time. Developed in the mid-1990s, it undertook a slow but steady march to the top. Offering an interface with good speeds and a compact connector, it became the standard for hooking up interface devices, storage, and even became the de-facto way to talk old-school serial, too.

In late 2014, the USB Implementers Forum finalised the standard for the USB-C plug. Its first major application was on smartphones like the Nexus 5X, and it has come to dominate the smartphone market, at least if you leave aside the iPhone. However, it’s yet to truly send USB-A packing, especially on the desktop. What gives? Continue reading “USB-C Is Taking Over… When, Exactly?” →