Bad Apple But It’s 6,500 Regex Searches In Vim

January 11, 2025 by Maya Posch 7 Comments

In the world of showing off, there is alongside ‘Does it play Doom?’ that other classic of ‘Does it play Bad Apple?’. Whereas either would be quaint in the context of the Vim editor, this didn’t deter [Nolen Royalty] from making Vim play the Bad Apple video. As this is a purely black and white video, this means that it’s possible to convert each frame into a collection of pixels, with regular expression based search and custom highlighting allowing each frame to be rendered in the Vim window.

The fun part about this hack is that it doesn’t require any hacking or patching of Vim, but leans on its insane levels of built-in search features by line and column, adjusting the default highlight features and using a square font to get proper pixels rather than rectangles. The font is (unsurprisingly) called Square and targets roguelike games with a specific aesthetic.

First 6,500 frames are fed through ffmpeg to get PNGs, which are converted these into pixel arrays using scripts on the GitHub project. Then the regex search combined with Vim macros allowed the video to be played at real-time speed, albeit at 120 x 90 resolution to give the PC a fighting chance. The highlighting provides the contrast with the unlit pixels, creating a rather nice result as can be seen in the embedded video.

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Tactility; The ESP32 Gets Another OS

January 11, 2025 by Jenny List 11 Comments

Doing the rounds this week is a new operating system for ESP32 microcontrollers, it’s called Tactility, and it comes from [Ken Van Hoeylandt]. It provides a basic operating system level with the ability to run apps from an SD card, and it has the choice of a headless version or an LVGL-based touch UI.

Supported devices so far are some Lillygo and M5Stack boards, with intriguingly, support in the works for the Cheap Yellow Display board that’s caught some attention recently. The term “ESP32” is now a wide one encompassing Tensilica and RISC-V cores and a range of capabilities, so time will tell how flexible it is for all branches of the family.

We find this OS to be interesting, both in its own right and because it joins at least two others trying to do the same thing. There’s [Sprite_TM]’s PocketSprite mini console, and the operating system used by the series of Netherlands hacker camp badges, We’ll be trying to get a device running it, in order to give you a look at whether it’s suitable for your projects. If it runs well on the cheaper hardware, it could be a winner!

Regular (Expression) Chess

January 7, 2025 by Al Williams 17 Comments

[Nicholas Carlini] found some extra time on his hands over the holiday, so he decide to do something with “entirely no purpose.” The result: 84,688 regular expressions that can play chess using a 2-ply minmax strategy. No kidding. We think we can do some heavy-duty regular expressions, but this is a whole other level.

As you might expect, the code to play is extremely simple as it just runs the board through series of regular expressions that implement the game logic. Of course, that doesn’t count the thousands of strings containing the regular expressions.

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Nottingham Railway departure board in Hackspace

All Aboard The Hack Train: Nottingham’s LED Revival

January 4, 2025 by Heidi Ulrich 4 Comments

Hackerspaces are no strangers to repurposing outdated tech, and Nottingham Hackspace happens to own one of those oddities one rarely gets their hands on: a railway departure board. Left idle for over a decade, it was brought back to life by [asjackson]. Originally salvaged around 2012, it remained unused until mid-2024, when [asjackson] decided to reverse-engineer it. The board now cycles between displaying Discord messages and actual train departures from Nottingham Railway Station every few minutes. The full build story can be found in this blog post.

The technical nitty-gritty is fascinating. Each side of the board contains 4,480 LEDs driven as two parallel chains. [asjackson] dove into its guts, decoding circuits, fixing misaligned logic levels, and designing custom circuit boards in KiCAD. The latest version swaps WiFi for a WizNet W5500 ethernet module and even integrates the Arduino Uno R4 directly into the board’s design. Beyond cool tech, the display connects to MQTT, pulling real-time train data and Discord messages via scripts that bridge APIs and custom Arduino code.

This board is a true gem for any hackerspace, even more so now it’s working. It waited for the exact mix of ingredients why hackerspaces exist in the first place: curiosity, persistence, and problem-solving. Nottingham Hackspace is home to a lot more, as we once wrote in this introductory article.If you don’t have room for the real thing, maybe set your sights a bit smaller.

Do you have a statement piece this cool in your hackerspace or your home? Tip us!

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38C3: Save Your Satellite With These Three Simple Tricks

December 30, 2024 by Elliot Williams 11 Comments

BEESAT-1 is a 1U cubesat launched in 2009 by the Technical University of Berlin. Like all good satellites, it has redundant computers onboard, so when the first one failed in 2011, it just switched over to the second. And when the backup failed in 2013, well, the satellite was “dead” — or rather sending back all zeroes. Until [PistonMiner] took a look at it, that is.

Getting the job done required debugging the firmware remotely — like 700 km remotely. Because it was sending back all zeroes, but sending back valid zeroes, that meant there was something wrong either in the data collection or the assembly of the telemetry frames. A quick experiment confirmed that the assembly routine fired off very infrequently, which was a parameter that’s modifiable in SRAM. Setting a shorter assembly time lead to success: valid telemetry frame.

Then comes the job of patching the bird in flight. [PistonMiner] pulled the flash down, and cobbled together a model of the satellite to practice with in the lab. And that’s when they discovered that the satellite doesn’t support software upload to flash, but does allow writing parameter words. The hack was an abuse of the fact that the original code was written in C++. Intercepting the vtables let them run their own commands without the flash read and write conflicting.

Of course, nothing is that easy. Bugs upon bugs, combined with the short communication window, made it even more challenging. And then there was the bizarre bit with the camera firing off after every flash dump because of a missing break in a case statement. But the camera never worked anyway, because the firmware didn’t get finished before launch.

Challenge accepted: [PistonMiner] got it working, and after fifteen years in space, and ten years of being “dead”, BEESAT-1 was taking photos again. What caused the initial problem? NAND flash memory needs to be cleared to zeroes before it’s written, and a bug in the code lead to a long pause between the two, during which a watchdog timeout fired and the satellite reset, blanking the flash.

This talk is absolutely fantastic, but may be of limited practical use unless you have a long-dormant satellite to play around with. We can nearly guarantee that after watching this talk, you will wish that you did. If so, the Orbital Index can help you get started.

Bringing OpenStreetMap Data Into Minecraft

December 30, 2024 by Tom Nardi 11 Comments

Over the years, dedicated gamers have created incredible recreations of real (and not so real) locations and structures within the confines of Minecraft. Thanks to their efforts, you can explore everything from New York city to Middle Earth and the U.S.S. Enterprise in 1:1: scale.

But what if you wanted to recreate your own town, and didn’t have the hundreds of hours of spare time necessary to do it by hand? Enter Arnis, an open source project from [Louis Erbkamm] that can pull in geographic data from OpenStreetMap and turn it into a highly detailed Minecraft map with just a few keystrokes.

The tool, written in Rust, can be either run via an interactive graphical interface or on the command line. In either case, you provide Arnis with the latitude and longitude for a bounding box around whatever you want to import into the game. [Louis] warns that the resulting process is fairly computationally heavy, so you should start be experimenting with small areas.

Once generated, the map can be loaded into the Java Edition of Minecraft. This refers to the original build of the game that predates the Microsoft buyout. Once Redmond took over they spearheaded a new version of the game written in C++ which was then ported over to mobile operating systems and game consoles. Long story short, if you want to wander around a Minecraft version of your home town, you’ll have to do it on your desktop computer instead of your Nintendo Switch.

While the tool is usable in its current state, [Louis] has a fairly long list of features that either still need to be implemented or could use some improvements. From the number of pull requests that have been merged in, it looks like any assistance the community can provide to make Arnis as capable as possible is welcome, so feel free to lend a hand if you’ve got that geospatial fever.

We’ve seen several examples of hackers bringing objects from Minecraft into the physical world, so it’s refreshing to see a bit of our reality sneaking into the game’s blocky universe.

Porting Dragon’s Lair To The Game Boy Color Was A Technical Triumph

December 28, 2024 by Donald Papp 5 Comments

If you remember the 80s arcade game Dragon’s Lair, you probably also remember it was strikingly unlike anything else at the time. It didn’t look or play like anything else. So it might come as a surprise that it was ported to Nintendo’s Game Boy Color, and that took some doing!

Dragon’s Lair used LaserDisc technology, and gameplay was a series of what we’d today call quick-time events (QTE). The player essentially navigated a series of brief video clips strung together by QTEs. Generally, if the player chose correctly the narrative would progress. If they chose poorly, well, that’s what extra lives (and a stack of quarters) were for.

More after the break!

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