Play Your Favorite Nokia Game On The Raspberry Pi Pico

May 11, 2021 by Lewin Day 6 Comments

In many people’s memories, Snake lived and breathed on Nokia handsets from the late 90s and early 2000s. However, the game has been around for much longer than that, and will continue to live on in the future. That’s at least in part thanks to people like [Hari Wiguna] keeping it alive by implementing it on new platforms.

[Hari] set about writing Snake in MicroPython for the Raspberry Pi Pico. The hardware side of things is simple enough – five buttons hooked up to the Pico, along with an 128×64 I2C OLED screen to display the game on. On the software side of things, [Hari] pushed the boat out, deciding that his version of Snake had to have the player character slither like the real thing. This took a little effort to get right, particularly when navigating corners in different directions. However, perseverance paid off and [Hari] got the job done.

Code is on GitHub for those that want to tinker at home. It’s a tidy piece of work, though not the weirdest place we’ve seen the game appear – we’ve actually seen it run within PCB routing software before thanks to some nifty scripting. Video after the break. Continue reading “Play Your Favorite Nokia Game On The Raspberry Pi Pico” →

Smallest Discrete Transistor 555 Timer

May 11, 2021 by Chris Lott 28 Comments

Over at Tiny Transistor labs, [Robo] took it upon himself to reproduce the classic 555 timer in discrete transistor form. For bonus points, he also managed to put it in a package that’s the same basic size, pin compatible with, and a plug-in replacement for the original. The first task was deciding which 555 circuit to implement. He examined a handful of different implementations — and by examined, we mean dissected them and studied the die circuitry under a microscope. In the end, he went with Hans Camenzind’s original circuit, both as a tribute and because it used the fewest transistors — a point which helped manage the final size, which is only a little bit bigger than the IC!

Speaking of sizes, have you ever soldered an EIA 01005 resistor? We agree with [mbedded.ninja] who wrote on a post about standard chip resistor sizes, the 01005 is a “ridiculously small chip package that can barely be seen by the naked eye.” It is 16 thou x 8 thou (0.4 mm x 0.2 mm) in size, and despite its name and placement in the Imperial series, it is not half the size of an 0201. The transistors are your standard 2N3904 / 2N3906, but purchased in a not-so-standard DFN (Dual Flat Pack, No Leads). We might think a 1.0 x 0.6 mm component as small, but compared to its neighboring resistors in this circuit, it’s huge.

[Robo] has done this kind of project before, most recently making a discrete recreation of of the classic 741 op-amp. We covered a similar, but larger, discrete 555 timer project back in 2011. If you want to go really big-scale with your own reproduction project, check out the MOnSter 6502 from five years ago for further inspiration. Thanks to [Lucas] for the tip.

PHP Gets A Demoscene Engine Of Its Very Own

May 9, 2021 by Lewin Day 6 Comments

When we think demoscene, our first thought is typically of 80s computers, particularly the Commodore 64 and Amiga 500 which were widely regarded as the awesomest of their time. However, you can write a demo on any platform you wish, and [OxABADCAFE] has done just that – in PHP.

Going by PDE, standing for Pointless, Portable, or PHP Demo Engine, the code is available on GitHub for the curious. The code is set up for RGB ASCII terminal output, for a beautifully old-school aesthetic. Demo sequences can be programmed in JSON files, with the code executing a default in-built demo if none is provided.

There’s no audio yet, so you’ll have to cool your thumping chiptune jets until that’s available in a later release. With that said, we look forward to more development expanding what can be done with the engine – after all, there’s nothing more demoscene than pushing the limits. Video after the break.

Continue reading “PHP Gets A Demoscene Engine Of Its Very Own” →

3D Printed Camera Crane For The Workshop

May 5, 2021 by Danie Conradie 7 Comments

When you make a living building stuff and documenting the process camera setups take up a lot of time, breaking expensive equipment is an occupational hazard. [Ivan Miranda] knows this all too well, so he built a fully-featured camera crane to save his time and camera equipment. Video after the break.

The basic design is a vertical mast with a pivoting camera mounted to the end. The aluminum mast telescopes for increased vertical adjustability, and rides on a plywood base with caster wheels. The aluminum pivoting arm is counterweighed to offset the camera head, and a parallel bar mechanism allows the camera to hold a constant vertical angle with the ground. Thanks to the explosion of home gyms during the pandemic, gym weights were hard to find, so [Ivan] used an ammo can filled with sand and screws instead. A smaller sliding counterweight on top of the arm allows for fine-tuning. [Ivan] also wanted to be able to do horizontal sliding shots, so he added a pulley system that can be engaged with a clutch mechanism to keep a constant horizontal angle with the camera. Most of the fittings and brackets are 3D printed, some of them no doubt on his giant 3D printer.

We can certainly see this crane meeting its design objectives, and we can’t help but want one ourselves. [Alexandre Chappel] also built a camera crane a while back which utilized a completely different arm mechanism. As cool as these are, they still pale in comparison to [mingul]’s workshop-sized 8-axis CNC camera crane. Continue reading “3D Printed Camera Crane For The Workshop” →

Lego Wheels And Tracks Benchmarked For Your Pleasure

May 4, 2021 by Lewin Day 7 Comments

For many people, Lego is their first entry into the world of engineering. With the Technic line of building blocks complete with all manner of gears and shafts and wheels, there’s a ton of fun to be had while learning about the basic principles of mechanical things. The [Brick Experiment Channel] takes Lego quite seriously in this context, and has collected data concerning the performance of a variety of Lego wheels and tracks.

The testing setup is simple. A small vehicle is fitted with a particular set of Lego wheels or tracks. Then, it’s placed on an inclined wooden board. The angle of inclination is then increased until the vehicle neither climbs the board nor slips down it. This angle can then be used to calculate the coefficient of friction of the given tyre or track set. [Brick Experiment Channel] filmed this testing and collected data on 33 different wheel and track combinations, publishing it in the description of the Youtube video.

Interestingly, the date of release of the various parts is recorded with the data. This is interesting as one would expect older rubber parts to lose grip with age, however, the release date of the parts obviously does not correspond with the manufacturing date, so the utility of this is somewhat unclear. There’s also some surprising results, with what appear to be soft, flat and smooth rubber wheels performing somewhat worse than those with curved profiles that you’d expect to have less contact patch. Regardless, it’s the best data we’ve ever seen in this field and we think it’s great that it was collected and shared with the broader Lego community. We look forward to seeing more of this in future, as it’s obviously something of great use to builders. We can imagine it would have proved handy when [Brick Experiment Channel] built their obstacle climbing rover. Video after the break.

Continue reading “Lego Wheels And Tracks Benchmarked For Your Pleasure” →

Enjoy An ASCII Version Of Star Wars In The Palm Of Your Hand For May The 4th

May 4, 2021 by Dan Maloney 13 Comments

Everyone by now has probably seen the original — and best; fight us — installment of the Star Wars franchise, and likely the ASCII-art animation version of it that improves greatly on the film by eliminating all those distracting special effects, human actors, and the soundtrack. But what we haven’t had until now is a portable player for ASCIIWars, to enjoy the film in all its character-based glory while you’re on the go.

While this tribute to [Simon Jansen]’s amazing ASCII-art achievement might seem like a simple repackaging of the original, [Frank] actually had to go to some lengths to make this work. After getting [Simon]’s blessing, the build started with a WEMOS D1 Mini, a good platform for the project less for its wireless capabilities and more for its 4 MB of flash memory. A 240×360 TFT LCD display was selected to show the film; the scale of the display made most fonts hard to read, so [Frank] used Picopixel, a font designed for legibility on small screens. The animation file is stored on the SPIFFS file system on the D1’s flash memory, and a few lines of code parse it and send it to the display. The final touch is mounting the whole thing is an old slide viewer, which magnifies the display to make it a little easier to see.

As much as we applaud [Frank]’s tribute to [Simon]’s effort, there’s no reason to confine this to the Star Wars universe. If you read up on the history of ASCII art, which goes surprisingly far back, you might be inspired to render another classic film in ASCIImation and put it on a viewer like this. ASCII-Metropolis, anyone?

Continue reading “Enjoy An ASCII Version Of Star Wars In The Palm Of Your Hand For May The 4th” →

I2C Paper Tape Reader Is Not What You Think

May 3, 2021 by Chris Lott 26 Comments

We’re not quite sure what drove the development of this project, but [shapoco] has put together an intriguing device that reads I2C signals (Japanese Twitter link) which have been printed as black and white rectangles on paper tape. He wrote a program that prints an I2C byte stream onto strips containing the SCL and SDA signal patterns. Once printed, you cut the strips from the paper and glue them together into one long piece, making a complete message — in this case, commands to a small LCD screen that will display the phrase “Hello, Tape I2C”.

We’re not sure exactly sure what’s inside that rectangular widget epoxied to the bottom of that perf board through which the tape passes. But clearly, it must contain a pair of LEDs to illuminate the tape and a pair of sensors to detect the reflection off the tape (looking at the wiring, it seems unlikely that anything is mounted underneath the tape). According to one machine-translated Twitter message, detection is done using a Schmitt trigger made from an LM393 comparator with hysteresis (see this TI app note for a review of this type of circuit). Here’s a scope capture of the resulting signals. [Shapoco] notes that the circuit can operate much faster — the tape is being pulled slowly in the video to make it easier to see.

This is not [shapoco]’s first experiment in optical I2C communications. Check out the second video down below where he’s reading I2C signals from a computer’s display. One person tweeted about how software source code was sometimes printed optically in old Byte magazines many years ago, a topic we talked about in Hackaday Podcast #049 last year when discussing Cauzin strips.

Besides just being cool, and possibly helpful as an educational device, does this technique have any real-world applications these days? Let us know your thoughts in the comment section below. Thanks to [Manawyrm] for sending us this tip.

Continue reading “I2C Paper Tape Reader Is Not What You Think” →