Greeking Out With Arduinos

Learning a new language is hard work, but they say that the best way to learn something is to teach it. [Angeliki Beyko] is learning Greek, and what better way to teach than to build a vocabulary flash-card game from Arduinos, color screens, 1602 text screens, and arcade buttons? After the break, we have a video from the creator talking about how to play, the hardware she chose, and what to expect in the next version.

Pegboard holds most of the hardware except the color screens, which are finicky when it comes to their power source. The project is like someone raided our collective junk drawers and picked out the coolest bits to make a game. Around the perimeter are over one hundred NeoPixels to display the game progress and draw people like a midway game. Once invested, you select a category on the four colored arcade buttons by looking at the adjacent LCD screens’ titles. An onboard MP3 shield reads a pseudo-random Greek word and displays it on the top-right 1602 screen in English phonetics. After that, it is multiple choice with your options displaying in full-color on four TFT monitors. A correct choice awards you a point and moves to the next word, but any excuse to mash on arcade buttons is good enough for us.

[Angeliki] does something we see more often than before, she’s covering what she learned, struggled with, would do differently, and how she wants to improve. We think this is a vital sign that the hacker community is showcasing what we already knew; hackers love to share their knowledge and improve themselves.

Typing Greek with a modern keyboard will have you reaching for an alt-code table unless you make a shortcut keyboard, and if you learn Greek, maybe you can figure out what armor they wore to battle.

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Parsing Math In Python

Programming computers used to be harder. Don’t get us wrong — today, people tend to solve harder problems with computers, but the fundamental act of programming is easier. We have high-level languages, toolkits, and even help from our operating systems. Most people never have to figure out how to directly read from a disk drive, deblock the data into records, and perform multiplication using nothing but shifts and adds. While that’s a good thing, sometimes it is good to study the basics. That was [gnebehay’s] thought when his university studies were too high level, so he decided to write an arithmetic expression parser in Python. It came out in about 100 lines of code.

Interpreting math expressions is one of those things that seems simple until you get into it. The first problem is correctly lexing the input — a term that means splitting into tokens. For a human, it seems simple that 5-3 is three tokens, {5, -, and 3} and that’s easy to figure out. But what about 5+-3? That’s also three tokens: {5,+,-3}. Tricky.

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Wooden Disc Player Translates Binary Back Into Text

[jbumstead] used MATLAB to convert the text messages into binary to be cut out of the disk.
[jbumstead] wanted to demonstrate the idea of information-storing devices such as LPs, CDs, and old hard drives. What he came up with lies directly at the intersection of art and technology: an intricately-built machine that plays beautiful collaged wooden disks. Much like the media that inspired the Wooden Disk Player, it uses a laser to read encoded data, which in this case is short bits of text like “Don’t Panic”.

These snippets are stored in binary and read by a laser and photodiode pair that looks for holes and not-holes in the disk. The message is then sent to an Arduino Nano, which translates it into English and scrolls the text on an LED matrix. For extra fun, the Nano plays a MIDI note every time it reads a 1, and you can see the laser reading the disk through a protective acrylic shield.

Though the end result is fantastic, [jbumstead] had plenty of issues along the way which are explored in the build video after the break. We love it when people show us their mistakes, because it happens to all of us and we shouldn’t ever let it tell us to stop hacking.

If anyone knows their way around lasers, it’s [jbumstead]. We loved playing their laser harp at Supercon!

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Falcon 9 Lamp Is Touching Down In The Living Room

Many of us have been inspired by the videos of the Falcon 9 booster, tall as an office building, riding a pillar of flame down to a pinpoint landing at Kennedy Space Center or on one of SpaceX’s floating landing pads in the ocean. It’s not often that we get to see science fiction fantasy become reality on such a short timescale, and while they might not be sold on the practicality of reusable rockets, even the most skeptical of observers have to admit it’s an incredible feat of engineering.

Though it can’t quite compare to the real thing, this 1:60 scale Falcon 9 lamp by [Sir Michael II] promises to bring a little of that excitement home every time you flick on the light. Combining a scratch built model of the reusable booster with some RGB LEDs, the hovering tableau recreates the tense final seconds before the towering rocket comes to a rest on its deployable landing legs. We imagine those last moments must seem like an eternity for the SpaceX engineers watching from home as well.

The LED “exhaust” without the fluff.

[Michael] walks readers through assembling the Falcon 9 model, which cleverly uses a 2 inch white PVC pipe as the fuselage. After all, why waste the time and material printing a long white cylinder when you can just buy one at the hardware store for a few bucks?

Dressed up with 3D printed details from Thingiverse user [twuelfing] and splashed with a bit of paint, it makes for a very convincing model. While the diameter of the pipe isn’t quite right for the claimed 1:60 scale, unless Elon Musk is coming over your place to hang out, we don’t think anyone will notice.

The rocket is attached to the pad with a piece of threaded steel rod, around which [Michael] has wrapped one meter of RGB LEDs controlled by an Arduino Uno. With some polyester fiber filler as a diffuser and a bit of code to get the LEDs flickering, he’s able to produce a realistic “flame” that looks to be coming from the Falcon 9’s center engine. While we admit it may not make a very good lamp in the traditional sense, it certainly gets extra points for style.

We’ve actually seen a similar trick used before to light up the engines of a LEGO Saturn V and Apollo Lunar Module. It’s amazing how realistic the effect can be, and we’d love to see it used more often. We’d also like to see more model rockets that actually levitate over their pads, but one step at a time.

Casio Computer Rebuild Puts New Wine In An Old Bottle

With a glut of vintage consumer electronics available from eBay it should be easy to relive your glory days, right? Unfortunately the march of time means that finding gear is easy but finding gear that works is not. So was the case when [Amen] acquired not one, but two used calculator/computer units hoping to end up with one working device. Instead, he went down the rabbit hole of redesigning his own electronics to drive the Casio QT-1 seen here.

Especially interesting is the prototyping process for the replacement board. [Amen] used a “BluePill” STM32 microcontroller board at its heart, and used point-to-point soldering for the rest of the circuitry on a rectangle of protoyping board. That circuit is non-trivial, needing a 23 V source to drive the original VFD from the computer, a battery-backed real-time-clock (MCP7940), and a GPIO expander to scan the keys on the keypad.

It worked great, but couldn’t be cut down to fit in the case. The solution was a PCB designed to fit the footprint of the original. The modern guts still need more firmware work and a couple of tweaks like nudging that 23 V rail a bit higher to 26 V for better brightness, but the work already warrants a maniacal cry of “It’s Alive!”.

This isn’t [Amen’s] first rodeo. Back in March we looked in on another vintage Casio refurb that sniffed out the display protocol.

The ZX Microdrive: Budget Data Storage, 1980s Style

An enduring memory for most who used the 8-bit home computers of the early 1980s is the use of cassette tapes for program storage. Only the extremely well-heeled could afford a disk drive, so if you didn’t fancy the idea of waiting an eternity for your code to load then you were out of luck. If you had a Sinclair Spectrum though, by 1983 you had another option in the form of the unique Sinclair ZX Microdrive.

This was a format developed in-house by Sinclair Research that was essentially a miniaturized version of the endless-loop tape carts which had appeared as 8-track Hi-Fi cartridges in the previous decade, and promised lightning fast load times of within a few seconds along with a relatively huge storage capacity of over 80 kB. Sinclair owners could take their place alongside the Big Boys of the home computer world, and they could do so without breaking the bank too much.

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Hackaday Podcast 085: Cable Robots Two-Ways, Cubic Raspberry Pi, Plastic Wrap Kayak, And Digging Inductors

Hackaday editors Mike Szczys and Elliot Williams take a look at all the hacks from the week that was. We think we’ve found the perfect tentacle robot, and its matching controller is also a tentacle. An unrelated project uses the same Bowden cable trick as the tentacle controller to measure deflection. If you’re more of a material-science geek, refining black sand to make your own inductors is a fascinating hack. And we wrap up the episode talking SSH keys and buses that go off road, but not in the way you might think.

Take a look at the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!

Direct download (~60 MB)

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