Hackaday Links: January 3, 2016

January 3, 2016 by Brian Benchoff 19 Comments

Cx5 is a strange material that’s a favorite of model makers and prop replicators. It’s kind of like a wax, kind of like a clay, and a little bit like a plastic. Now it’s a 3D printer filament. It looks very interesting for sculpted and highly detailed models, something the 3D printing scene hasn’t had yet.

So you want a CNC machine, right? Tormach makes a good one, and here’s what it takes to put a PCNC440 in your garage. This is an incredible amount of work and a great excuse to buy an engine hoist.

[Zemnmez] could find dozens of apps and webpages that would calculate resistor color codes for him automatically. What he couldn’t find is one that would do it in reverse – i.e. type in a resistor value and return the correct color code. He made this.

[aggaz] needed a way to connect multiple MIDI devices to his computer. The MIDI spec provides a neat piece of hardware for just this occasion – the MIDI thru box. The only thing you need to build a single MIDI thru box is an opto-isolator and a buffer. It’s easy enough to build, although the DIN5 jacks used for MIDI devices are pretty expensive nowadays. (FWIW- We get an invalid certificate error when loading this page but you should still be able to load it.)

AliExpress always has some interesting stuff on it, and [Ethan] found something very cool. They’re A8 CPUs found in the latest iPhone. Are they real? Who knows. I bought one, and you’re going to get pictures in another links post in a month or so.

The Game Boy Micro was released by Nintendo in 2005 and quickly became one of the coolest and most desired handheld consoles on the planet. You need only look at the eBay listings for the Micro as evidence of its desirability. [ModPurist] took an old DS Lite and converted it into a Game Boy Micro – same idea, larger package.

32C3: 20 Oscillators In 20 Minutes

January 3, 2016 by Elliot Williams 25 Comments

In terms of implausible stand-up comedy, [Darsha]’s “20 Oscillators in 20 Minutes” is pretty far out there. First of all, she’s sitting down, with googly eyes on her multimeter, and five breadboards and a mess of 9V batteries laid out in front of her. “Has anybody built electronics before? Has anybody built electronics in front of this many people before? Yeah, so you’d better f**king be nice.” And she’s off!

“Square waves are really good for your speakers.” And a few seconds later, a lub-dub beat-frequency oscillator filled the hall. And then there’s the stand-up clichés: “Anyone in the audience from Norway?!” And “Anyone know what chip I’m using here?” (The 555.) A heckler, or participant, shouts up “What are you doing?” She responds “Building this!” and shows a sketch of the basic layout.

She baits the audience — “Do you want to ask me about duty cycles?” — and tells stories: “And then one time the solder fell in my lap and burned through my crappy jeggings. Who knows what jeggings are? Whooo!!” All the while the clicking gets louder and more complicated.

Then there’s the suspense. “11 minutes left? Shit, I dunno if I’m going to make it this time!” She’s visibly panicked. A question: “How do you protect the outputs from overvoltage?” “I don’t. (pause, laughter) I use some filter caps and just, well, hope that you guys have good insurance.”

Nearing the home stretch, there’s this quasi-rhythmic ticking and pulsing slowly building up in the background. She plugs in another capacitor, and the crowd spontaneously applauds. A little bit later, she shouts “Is it loud enough?” over the din and turns it down. At the end, the timing’s getting really tight, and she calls up someone to help from the audience.

We won’t spoil it, naturally. You’ll just have to watch it run to the end. We laughed, we cried. It was better than Schroedinger’s cats.

(We’d use hex inverters.)

Source: Flibble CC-BY-SA 3.0 https://commons.wikimedia.org/wiki/File:Acorn-ARM-Evaluation-System.jpg

Reverse Engineering The IPhone’s Ancestor

January 3, 2016 by Brian Benchoff 59 Comments

By all accounts, the ARM architecture should be a forgotten footnote in the history of computing. What began as a custom coprocessor for a computer developed for the BBC could have easily found the same fate as National Semiconductor’s NS32000 series, HP’s PA-RISC series, or Intel’s iAPX series of microprocessors. Despite these humble beginnings, the first ARM processor has found its way into nearly every cell phone on the planet, as well as tablets, set-top boxes, and routers. What made the first ARM processor special? [Ken Shirriff] potsed a bit on the ancestor to the iPhone.

The first ARM processor was inspired by a few research papers at Berkeley and Stanford on Reduced Instruction Set Computing, or RISC. Unlike the Intel 80386 that came out the same year as the ARM1, the ARM would only have a tenth of the number of transistors, used one-twentieth of the power, and only use a handful of instructions. The idea was using a smaller number of instructions would lead to a faster overall processor.

This doesn’t mean that there still isn’t interesting hardware on the first ARM processor; for that you only need to look at this ARM visualization. In terms of silicon area, the largest parts of the ARM1 are the register file and the barrel shifter, each of which have two very important functions in this CPU.

The first ARM chip makes heavy use of registers – all 25 of them, holding 32 bits each. Each bit in a single register consists of two read transistors, one write transistor, and two inverters. This memory cell is repeated 32 times vertically and 25 times horizontally.

The next-largest component of the ARM1 is the barrel shifter. This is just a device that allows binary arguments to be shifted to the left and right, or rotated any amount, up to 31 bits. This barrel shifter is constructed from a 32 by 32 grid of transistors. The gates of these transistors are connected by diagonal control lines, and by activating the right transistor, any argument can be shifted or rotated.

In modern terms, the ARM1 is a fantastically simple chip. For one reason or another, though, this chip would become the grandparent of billions of devices manufactured this year.

7th Period Of The Periodic Table Complete

January 3, 2016 by Brian Benchoff 40 Comments

For the last fifty or so years, the periodic table has been incomplete. Elements after uranium on the periodic table have been synthesized for the past few decades, but there were always a few missing blocks in the periodic table. These elements, with atomic numbers of 113, 115, 117, and 118 comprise the missing parts of period 7 – the lowest row – of the periodic table. Now, IUPAC, the International Union of Pure and Applied Chemistry, has announced the verification of the discoveries of the last four elements of the seventh period of the periodic table.

With the announcement of the verification of discovery for these elements, they will get a name. Currently elements 113, 115, 117, and 118 are known as Ununtrium, Ununpentium, Ununseptium, and Ununoctium, respectively. What these elements will be named depends on the proposals by the discoverers of these elements.

Element 113 was discovered by researchers at the RIKEN laboratory in Japan, and these researchers will be able to propose a name and atomic symbol for their discovery. Elements 115, 117, and 118 were discovered through a partnership between the Joint Institute for Nuclear Research in Dubna, Russia, Lawrence Livermore National Laboratory in California, and Oak Ridge National Laboratory in Oak Ridge, Tennessee. Researchers at these three laboratories will propose names and atomic symbols for these three elements.

It should be noted that Lawrence Livermore National Laboratories and the Joint Institute for Nuclear Research in Dubna each have their own element named after them: Lawrencium and Dubnium, with atomic numbers 103 and 105, respectively. Having element 113, 115, and 118 named after Oak Ridge National Laboratory wouldn’t be a bad proposal, and would be rather fitting given the laboratory’s influence on the last half-century of physics.

Of particular interest is the naming of element 118. Because element 118 falls within group 18 of the periodic table, it is a noble gas, with a particular naming pattern. each of the elements in group 18 end with the suffix ~on, instead of the suffix for the rest of the periodic table, ~ium (helium is the exception to this rule due to historical precedent). Whether element 118 will use the ~on or ~ium suffix is up to debate; current IUPAC rules say all new elements should end with ~ium, but recommendations have been published to name all group 18 elements with the ~on suffix.

This is not the end of the periodic table by any means. It is possible that elements with higher atomic numbers can be synthesized. However, experiments to synthesize element 119 have so far come up short, and the predicted properties of element 119 put it at the limits of what current technology is able to detect.

BGA Hand Soldering Video

January 3, 2016 by Al Williams 31 Comments

By 2016, most people have got the hang of doing SMD soldering in the garage–at least for standard packaging. Ball Grid Array or BGA, however, remains one of the more difficult packages to work with [Colin O’Flynn] has an excellent video (almost 30-minutes, including some parts that are sped up) that shows exactly how he does a board with BGA.

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32C3: 3D Printing On The Moon

January 3, 2016 by Elliot Williams 36 Comments

How do you resist this talk title? You can’t! [Karsten Becker]’s talk about what kinds of 3D printers you’d use on the moon is a must-see.

[Part-Time Scientists] was a group of 35 people working on a mission to the moon. Then they won the qualifying round in the Google Lunar XPRIZE, got a bunch of money, and partnered with some heavy corporate sponsors, among which is Audi. Now they’ve added eleven full-time employees and updated the name to [PT Scientists]. (They’re taking applications if you’re interested in helping out!)

A really neat part of their planned mission is to land near the Apollo 17 landing site, which will let them check up on the old lunar rover that NASA left up there last time. The science here is that, 45 years on, they hope to learn how all of the various materials that make up the rover have held up over time.

But the main attraction of their mission is experimental 3D printing using in-situ materials. As [Karsten] says, “3D printing is hard…but we want to do it on the moon anyway.”

One idea is to essentially microwave the lunar regolith (and melt it) . This should work because there’s a decent iron component in the regolith, so if they can heat it up it should fuse. The catch with microwaving is directivity — it’s hard to make fine details. On the plus side, it should be easy to make structures similar to paved roads out of melted regolith. Microwave parts are robust and should hold up to launch, and microwaving is relatively energy efficient, so that’s what they’re going to go for.

But there are other alternatives. The European Space Agency is planning to bring some epoxy-like binder along, and glue regolith together in layers like a terrestrial cement printer. The problem is, of course, schlepping all of the binder to the moon in the first place.

And then there are lasers. [Karsten] talked lasers down a little bit, because they’re not very energy efficient and the optics are fidgety — not something you’d like to be supporting remotely from earth.

The final option that [Karsten] mentioned was the possibility of using locally-generated thermite to fuse regolith. This has been tested out on earth, and should work. [Karsten] thought it was an interesting option, but balls of hot thermite are potentially tough on rovers, and the cost of mistakes are so high that they’re going to put that off for a future mission.

In the end, the presentation ran only thirty minutes long, so there’s a great Q&A session after that. Don’t go home once you hear the audience clapping!

Better 3D Graphics On The Arduino

January 2, 2016 by Brian Benchoff 20 Comments

There are cheap LCDs available from China, and when plugged into an Arduino, these displays serve as useful interfaces or even shinier baubles for your latest project. [Michael] picked up a few of these displays in the hope of putting a few animated .GIFs on them. This is an impossible task with an ATMega microcontroller – the Arduino does not have the RAM or the processing power to play full-screen animations. It is possible to display 3D vector graphics, with an updated graphics library [Michael] wrote.

The display in question uses the ILI9341 LCD driver, found in the Adafruit library, and an optimized 3D graphics driver. Both of these drivers have noticeable flicker when the animation updates, caused by the delay between erasing a previous frame and when a new frame is drawn.

With 16-bit color and a resolution of 320×240 pixels, there simply isn’t enough memory or the processing power on an ATMega microcontroller to render anything in the time it takes to display a single frame. There isn’t enough memory to render off-screen, either. To solve this problem, [Michael] built his render library to only render pixels that are different from the previous frame.

Rendering in 3D presents its own problems, with convex surfaces that can overlap themselves. To fix this, [Michael]’s library renders objects from front to back – if the pixel doesn’t change, it doesn’t need to be rendered. This automatically handles occlusions.

In a demo application, [Michael]’s LCD and Arduino can display the Stanford bunny, a low-poly 3D face, and geometric object. It’s not a video game yet, but [Michael] thinks he can port the classic game Spectre to this platform and have it run at a decent frame rate.

Video of the demo below.

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