Purpose-Built Plotter Pitches In To Solve Wordblitz On Your Phone

July 23, 2022 by Dan Maloney No comments

It seems like most hackers have never played a game without at least wondering how to cheat at it. It’s not that we’re a dishonest lot, at least not as a rule. It’s more that most games hold less challenge for us than does figuring out how to reverse engineer the game’s mechanics. We don’t intend to cheat; it just sort of happens.

Or at least that’s the charitable way to look at such smartphone game cheats as this automated word-search puzzle solver. The game is Wordblitz, which is basically an implementation of classic Boggle along with extra features to release more dopamine and keep you playing. Not one to fall for that trick, [ghettobastler] whipped up a quick X-Y gantry from MDF using a laser cutter, added a stylus in the form of a cotton swab tipped with aluminum foil, and a vision system based on a simple web camera. The bed of the gantry has a capacitive plate so the stylus can operate the phone, along with a frame of ArUco fiducial marker to aid in locating the phone.

A Raspberry Pi handles the machine vision part of the process, which uses OpenCV to estimate the phone’s location and extract the current game tiles. The words in the game field are located by a solver that [ghetto] had previously written; a script then streams G-code to the plotter to peck out the answers at blazing speed, or at least faster than even [Peggy Hill] could manage. See the video below for a sample game being solved.

One word of warning if you choose to build this: [ghettobastler]’s puzzle-solving algorithm is based on a French dictionary, so you’ll have to re-teach it for other languages. But whatever language it’s in, this reminds us a bit of some of the Wordle solvers we’ve seen recently.

Continue reading “Purpose-Built Plotter Pitches In To Solve Wordblitz On Your Phone” →

SATAn Turns Hard Drive Cable Into Antenna To Defeat Air-Gapped Security

July 22, 2022 by Dan Maloney 19 Comments

It seems like [Mordechai Guri]’s lab at Ben-Gurion University is the place where air-gapped computers go to die, or at least to give up their secrets. And this hack using a computer’s SATA cable as an antenna to exfiltrate data is another example of just how many side-channel attacks the typical PC makes available.

The exploit, deliciously designated “SATAn,” relies on the fact that the SATA 3.0 interface used in many computers has a bandwidth of 6.0 Gb/s, meaning that manipulating the computer’s IO would make it possible to transmit data from an air-gapped machine at around 6 GHz. It’s a complicated exploit, of course, and involves placing a transmitting program on the target machine using the usual methods, such as phishing or zero-day exploits. Once in place, the transmitting program uses a combination of read and write operations on the SATA disk to generate RF signals that encode the data to be exfiltrated, with the data lines inside the SATA cable acting as antennae.

SATAn is shown in action in the video below. It takes a while to transmit just a few bytes of data, and the range is less than a meter, but that could be enough for the exploit to succeed. The test setup uses an SDR — specifically, an ADALM PLUTO — and a laptop, but you can easily imagine a much smaller package being built for a stealthy walk-by style attack. [Mordechai] also offers a potential countermeasure for SATAn, which basically thrashes the hard drive to generate RF noise to mask any generated signals.

While probably limited in its practical applications, SATAn is an interesting side-channel attack to add to [Dr. Guri]’s list of exploits. From optical exfiltration using security cameras to turning power supplies into speakers, the vulnerabilities just keep piling up.

Continue reading “SATAn Turns Hard Drive Cable Into Antenna To Defeat Air-Gapped Security” →

Cut Just About Anything With This Combination Lathe And Wire EDM

July 20, 2022 by Dan Maloney 18 Comments

They say that if you have a lathe, you have every other machine tool too. To some degree, that’s true — you can make almost anything on a lathe, including another lathe, and even parts best made on other machine tools can usually be made on a lathe in a pinch. But after seeing this lathe attachment for a DIY electric discharge machining tool, we might be inclined to see the EDM as the one machine tool to rule them all.

Now, we’ll admit that the job [BAXEDM] built this tool for might be a little contrived. He wanted to make some custom hex inserts for his Swiss Army knife, which seem like they’d have been pretty easy to make from hex bar stock in a conventional lathe. Then again, hardened steel is the kind of material that wire EDM was made for, and there seem to be many use cases for an attachment that can spin a workpiece against an EDM cutting wire.

That was really the trick of this build — spinning a part underwater. To accomplish this, [BAXEDM] built a platform to carry a bearing block that supports a standard ER-25 collet, with a bracket that holds a stepper clear of the water in the EDM cutting tank. There are plenty of 3D printed insulators too, to keep most of the attachment electrically isolated from the EDM current, plus exotic parts like ceramic bearings that won’t corrode under water. There were a ton of other considerations, too; [BAXEDM] goes through the long iterative design process in the video below, as well as taking his new tool for a literal spin starting at about the 27:00 mark.

If you’re intrigued by what EDM can accomplish — and who wouldn’t be? — but you need more background on the process, we’ve got you covered.

Continue reading “Cut Just About Anything With This Combination Lathe And Wire EDM” →

Modular Z80 Really Racks Up The Retrocomputer Cred

July 19, 2022 by Dan Maloney 24 Comments

Very few retrocomputing projects are anything other than a labor of love. There’s really no practical reason to build a computer that is woefully inadequate for just about any task compared to even an entry-level PC today. But the lack of a practical reason to do something rarely stops a hacker, as with this nifty modular Z80-based rack computer.

Actually, there’s at least one area where retrocomputers excel compared to their modern multi-core gigahertz counterparts — and that’s nostalgia. That’s what [Ricardo Kaltchuk] was going for with his build, which started by finding a Z80 and an Intel 8251 USART in his parts bin. Those formed the core of what would become the “Proton” computer, a modular beauty built around 7 cm by 10 cm PCBs that plug into a backplane inside a rack made from aluminum angle. Aside from the power supply and the Z80 CPU, other modules include a RAM card with a zero insertion force socket for an EPROM, a mass-storage module sporting a 128 MB Compact Flash card, plus modules for standard serial and I2C comms.

The fit and finish are excellent, and the performance is impressive. The Proton runs CP/M and boasts a ton of old applications that will bring back some memories, like SuperCalc and dBase. We’d venture a bet that WordStar is in there someplace, or easily could be. The video below is a little rough, but shows everything off really well.

In some ways, the Proton reminds us of the RC2014, but its fit and finish are what bring this build home. That’s not to take away from the work [Ricardo] obviously put into documentation, though. The 62-page manual has every detail of every module, plus instructions for building one of your own.

Continue reading “Modular Z80 Really Racks Up The Retrocomputer Cred” →

Hackaday Links: July 17, 2022

July 17, 2022 by Dan Maloney 9 Comments

Webb’s first deep-field image. Source: NASA

The folks at NASA are taking a well-deserved victory lap this week after the splashy reveal of the first scientific images from the James Webb Space Telescope. As we expected, the first public release included a lot of comparisons to images obtained from Hubble, as the general public understandably sees Webb as the successor to the venerable space telescope, now in its third decade of service. So for a “let’s see what this baby can do” image, they turned Webb loose on a tiny patch of sky in the southern hemisphere containing galactic cluster SMACS 0723, and sent back images and spectroscopic data from galaxies up to 13 billion light years away. There are plenty of analyses of Webb’s deep field and the other images in the first release, but we particularly liked the takes by both Anton Petrov and Dr. Becky. They both talk about the cooler scientific aspects of these images, and how Webb is much more than just a $10 billion desktop image generator.

Continue reading “Hackaday Links: July 17, 2022” →

Impatience Is A Virtue When Testing This Old Maritime Teleprinter

July 16, 2022 by Dan Maloney 1 Comment

[Larry Wall], inventor of Perl, once famously said that programmers have three key virtues: sloth, hubris, and impatience. It’s safe to say that these personality quirks are also present in some measure in most hardware hackers, too, with impatience being perhaps the prime driver of great hacks. Life’s too short to wait for someone else to build it, whatever it may be.

Impatience certainly came into play for [Sebastian (AI5GW)] while hacking a NAVTEX receiver (in German). The NAVTEX system allows ships at sea to receive text broadcast alerts for things like changes in the weather or hazards to navigation. The trouble is, each NAVTEX station only transmits once every four hours, making tests of the teleprinter impractical. So [Sebastian]’s solution was to essentially create his own NAVTEX transmitter.

Job one was to understand the NAVTEX protocol, which is a 100-baud, FSK-modulated signal with characters encoded in CCIR 476. Since this encoding is also used in amateur radio teletype operations, [Sebastian] figured there would surely be an Arduino library for encoding and decoding it. Surprisingly, there wasn’t, but there is now, allowing an Arduino to produce the correct sequence of pulses for a CCIR 476-encoded message. Fed into a function generator, the mini-NAVTEX station’s signal was easily received and recorded by the painfully slow teleprinter. There’s that impatience again.

We thought this was a neat hack, and we especially appreciate that [Sebastian]’s efforts resulted in a library that could be useful to hams and other radio enthusiasts in the future. We’ve talked about some more modern amateur radio digital modes, like WSPR and FT8, but maybe it’s time to look at some other modes, too.

Continue reading “Impatience Is A Virtue When Testing This Old Maritime Teleprinter” →

Collaborative Effort Gets Laser Galvos Talking G-Code

July 15, 2022 by Dan Maloney 9 Comments

Everyone should know by now that we love to follow up on projects when they make progress. It’s great to be able to celebrate accomplishments and see how a project has changed over time. But it’s especially great to highlight a project that not only progresses, but also gives back a little to the community.

That’s what we’re seeing with [Les Wright]’s continuing work with a second-hand laser engraver. It was only a few weeks ago that we featured his initial experiments with the eBay find, a powerful CO₂ laser originally used for industrial marking applications. It originally looked like [Les] was going to have to settle for a nice teardown and harvesting a few parts, but the eleven-year-old tube and the marking head’s galvanometers actually turned out to be working just fine.

The current work, which is also featured in the video below, mainly concerns those galvos, specifically getting them working with G-code to turn the unit into a bit of an ad hoc laser engraver. Luckily, he stumbled upon the OPAL Open Galvo project on GitHub, which can turn G-code into the XY2-100 protocol used by his laser. While [Les] has nothing but praise for the software side of OPAL, he saw a hardware hole he could fill, and contributed his design for a PCB that hosts the Teensy the code runs on as well as the buffer and line driver needed to run the galvos and laser. The video shows the whole thing in use with simple designs on wood and acrylic, as well as interesting results on glass.

Of course, these were only tests — we’re sure [Les] would address the obvious safety concerns in a more complete engraver. But for now, we’ll just applaud the collaboration shown here and wait for more updates.

Continue reading “Collaborative Effort Gets Laser Galvos Talking G-Code” →