Storing 32 Bits Of Data In A Piece Of Glass

November 9, 2012 by 35 Comments

After finding an old piezoelectric delay line in an old TV, [Mike] decided to figure out how it works and in the process stored his name in sound waves reflecting inside a piece of glass

[Mike] was intrigued by these old-fashioned delay lines after watching [Dave] from EEVblog’s teardown of an circa 1985 camcorder. [Dave] found a piezoelectric delay line in his camcorder – a device that is able to store digital data by sending a sound wave into a glass plate, letting the sound wave bounce through the plate. and picking up the sound on the other end. It’s actually not too dissimilar to a mercury delay line used in the earliest computers.

After sending a pulse through his piezoelectric delay line, [Mike] picked up an echo almost exactly 64 microseconds later. After hooking up a simple circuit constructed out of a 74-series chip, [Mike] found he could ‘loop’ the delay line and keep a pulse going for up to 3 milliseconds.

Three milliseconds isn’t much, but by injecting serial data into the delay line, [Mike] was able to spell out his name in binary, as seen above. It’s just 32 bits stored for a fraction of a second, making it a very volatile, low-capacity memory, but functionally equivalent to the old mercury delay lines of yore.

It’s certainly not what [Mike] or [Dave]’s delay line was designed to do; these video delay lines were used to hold the previous line of video for a form of error correction. Outside [Mike]’s workbench and a few museums, though, you won’t see a delay line used as a form of computer memory. A very cool build and an awesome history lesson, and we thank [Mike] for that.

Netduino Gets A Huge Upgrade

November 9, 2012 by 12 Comments

The Netduino, a dev board built around the .NET Micro framework with the goal of being compatible with Arduino shields just got a huge upgrade.

The new Netduino Plus 2 features an upgraded STM32 ARM Cortex-M4 uC running at 168 MHz, improving on the original Netduino’s ARM7 running at 47 MHz. In addition to some more processing power, the STM32-based microcontroller has twice the RAM and six times as much Flash memory. Also, Ethernet (10Mbps), a MicroSD card port, and of course compatibility with all Arduino shields – including the new Arduino ‘Revision C’ boards for the Leonardo – remains intact.

In keeping with the design goals of the Netduino, the new board uses the .NET Micro Framework running under Windows. It looks like OS X and Linux users won’t be left out in the cold for long, though; there’s a project to port the .NET Micro stuff over to Mono.

Tip ‘o the hat to [Jason] for sending this one in.

Hardsync – DDR Reimagined For The C64

November 9, 2012 by 10 Comments

hardsync

For those of you that like to play dance games, but [DDR] for the [PS2] uses too modern hardware for your tastes, [Hardsync] may be for you. Although the chiptune-style music coming out of the [C64] may not appeal to everyone, one would have to imagine that a game like this could have been a huge hit 30 years ago.

As for the hardware itself, it does indeed use one PS2 element, the dance mat. It’s hooked into one of the C64 joystick ports. In this case, the cable was cut, but it would also be possible to make a non-destructive adapter for it so as not to interfere with any future PS2 fun.

The program is made so that fellow retro-dancers can make their own songs. Each song is a discreet file, and can be reconfigured to your own personal mix. Be sure to check out the video after the break of this old-school dance machine in use after the break! Continue reading “Hardsync – DDR Reimagined For The C64” →

KegDroid Makes Drinking Beer More Fun

November 8, 2012 by 16 Comments

KegDroid beer arduino

Are you bored with just drinking beer? Are your friends constantly sneaking into your house and stealing your sacred beverages? If so, perhaps you need KegDroid – the Android controlled beer tap created by [Paul Carff].

Looking for a way to add more excitement to drinking his beer, [Paul] spiced up his tap with a little extra technology. He added an Android tablet for touchscreen navigation of the menus, an Arduino to control the flow sensors and solenoid valves, and an NFC reader to act as security for restricted access.  Users must be authenticated before they are allowed to pour any alcohol.

Your name and photo are pulled from your Google+ account as you’re logged in, then you simply select your beverage of choice, and if you’d like a one, eight, or twelve ounce pour. Flow sensors automatically shut off when you have the desired quantity.

Seems like you get more foam than beer, but all in all it’s a cool bar top app.

Check out the video after the break.

Continue reading “KegDroid Makes Drinking Beer More Fun” →

Zelda Is The Princess, Now Link Is Too

November 8, 2012 by 43 Comments

[Mike] is a huge fan of The Legend of Zelda: The Wind Waker and now that he has a daughter it’s a great time to pass this epic quest down to the next generation. There’s a problem with explaining the plot to her daughter, though: even though the player can name the character after themselves, there’s no way to change the gendered pronouns. Yes, it’s a problem that could have been solved by a cameo by Professor Oak asking, “Are you a boy or a girl?’ but [Mike] came up with a better solution: changing all the pronouns with a ROM hack.

There are a few ‘problems’ with altering the dialogue with a ROM hack. Most importantly, all the new pronouns need to be the same length as the words they replace. [Mike] is using the word ‘milady’ to replace ‘my lad’ and ‘master,’ but also had to take a page from critiques of modern epics and replace ‘swordsman’ with ‘swordmain.’

So far, everything is working as planned and the [Mike]’s daughter [Maya] is enjoying seeing herself sail her dragon ship and battle foes. It’s a great effort to bring some semblance of gender neutrality to a classic game, and an awesome project for a really great dad.

Thanks to [Guillaume] for sending this one in.

The Band’s Name In Lights, RGB LEDs To Be Exact.

November 8, 2012 by 18 Comments

A few of [michu]’s friends formed a band named Kalikut Now and needed an awesome stage show. The band made a few 80cm-high letters of their band name, cut a few pieces of acrylic, and wired them up with a few LED modules. The work of connecting these letters to a computer and programming them fell on [michu], and we’ve got to say he did a pretty good job.

You may remember [michu] from his StripInvaders and PixelInvaders projects, basically a few RGB LED modules that can communicate with an Arduino over an SPI interface. With these huge letters, [michu] ran into a problem: he had 11 meters of cabling between the clock and data lines, far beyond the maximum recommended length for any datasheet.

[michu] looked around the Internet for common problems with SPI interfaces and found a lot of good advice from a lot of very smart people. The issue with the SPI bus was eventually solved by correctly wiring the grounds of his LED modules, building a few dead-simple SPI buffers, and reducing the clock speed of the SPI bus.

After countless hours, the band’s name is in lights, and RGB LEDs to boot. Everything can be controlled with Abelton Live, and looks absolutely fantastic as seen in the video after the break.

Continue reading “The Band’s Name In Lights, RGB LEDs To Be Exact.” →

Raspberry Pi Gets RISC OS, Can Now Play Elite

November 8, 2012 by 32 Comments

The processor in the Raspberry Pi – an ARM11 built by Broadcom – actually has a long and storied history. Much as how the Intel i7 in a top-of-the-line desktop can still run code written for the original IBM PC, the ARM chip in the Raspberry Pi is also based on decades-old technology.

The first ARM-based computer was the Acorn Archimedes, a mid-80s computer with 512kB of RAM and no hard drive. The Archimedes ran RISC OS, a very nice graphical operating system written explicitly for the ARM architecture. RISC OS is now available for the Raspberry Pi, finally bridging the gap between educational computers from 1987 and 2012.

Of course, a very much updated version of 25-year-old operating system running on a Raspberry Pi doesn’t mean much without a ‘killer app,’ does it? For the original Acorn Archimedes the killer app – and one of the best video games of the 80s – was Elite, a space trading and combat game that featured vector-style ships. [Pete Taylor] downloaded the Raspi RISC OS image and got Elite running using an Archimedes emulator and, of course, the Archimedes port of Elite.

It’s a pretty neat development if you’re in to alternative OSes and one of the best space-based games ever made. Well worth a download, at the very least.