Digital Rain Animation Crammed Into Pi Pico

January 12, 2022 by Lewin Day 6 Comments

With a new Matrix movie now in cinemas, we’ve all been reminded of those screensavers that were just the coolest thing ever when the original film dropped in 1999. [en0b] decided to recreate the classic “digital rain” effect on the Raspberry Pi Pico, using up all the little microcontroller’s storage in the process.

Rather than rely on existing graphics libraries, [en0b] set about using a high-quality GIF for the animation. The original file was 8 MB, which was far too big to fit on the Pico. After some finagling in an image editor and with the help of a custom Python script, however, [en0b] managed to fit the 127-frame animation at 240 x 135 resolution into the 2 MB Flash onboard the chip. With the microcontroller hooked up to the 1.14″ IPS “Pico Display” from Pimoroni, the final looks great and faithfully recreates the aesthetic seen in the film.

[en0b]’s technique could reliably be used for displaying any GIF that you can cut down to 14 to 16 colors without losing too much quality. It’s not the world’s highest-end graphics format, but it does the job for little animations like these.

We’ve seen similar builds before too, using more heavy-duty hardware to build a magic 8-ball in much the same way. Meanwhile, if you’ve got your own neat little GIF hacks or Pico projects, don’t hesitate to send them in!

Matrix Digital Rain On The IBM PC With A High Persistence Monitor

January 3, 2022 by Dave Rowntree 11 Comments

Unless you’ve been hiding under a rock for the last 20-odd years, you will have come across The Matrix series of movies, and the cool green ‘digital rain’ effect used frequently. This inspired [Oli Wright] to wonder what it would look like if instead of running the animation on a modern display, using a digitally produced phosphor persistence effect, it was implemented on some retro PC hardware, using an actual high-persistence phosphor Green Monochrome monitor. (Video embedded, below) As luck would have it, [Oli] owns a 40-year-old IBM PC 5150 as well as the matching IBM 5151 monitor, so it was a simple matter to implement the effect in 8088 assembler to create falling sequences of characters. The final binary is less than 256 bytes!

The IBM 5151’s long display persistence was intended to reduce the visibility of display flicker due to the low scan rate, but has the unfortunate side effect of smearing horribly when the image changes. This is exactly what [Oli] needed to implement this effect and we think it looks jolly fine.

[Oli] made use of the excellent PCjs browser-based emulator written by [Jeff Parsons] to demonstrate what the software is doing, without the effect being evident. If you like, you can try it out for yourselves, as the assembly listing is available on the project GitHub.

Of course, we’ve covered the digital rain effect many. many times before, for example, with this Arduino Library, and here’s a custom PC case side panel from way back in December 2021, if you can remember those days.

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Electric Dreams Help Cows Survive The Desert Of The Real

December 3, 2019 by Tom Nardi 64 Comments

Pictures of a cow wearing a pair of comically oversized virtual reality goggles recently spread like wildfire over social media, and even the major news outlets eventually picked it up. Why not? Nobody wants to read about geopolitical turmoil over the holidays, and this story was precisely the sort of lighthearted “news” people would, if you can forgive the pun, gobble up.

But since you’re reading Hackaday, these images probably left you with more questions than answers. Who made the hardware, what software is it running, and of course, why does a cow need VR? Unfortunately, the answers to the more technical questions aren’t exactly forthcoming. Even tracking the story back to the official press release from the Ministry of Agriculture and Food of the Moscow Region doesn’t tell us much more than we can gather from the image itself.

But it does at least explain why somebody went through the trouble of making a custom bovine VR rig: calm cows produce more milk. These VR goggles, should they pass their testing and actually be adopted by the Russian dairy industry, will be the newest addition to a list of cow-calming hardware devices that farmers have been using for decades to get the most out of their herds.

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Building The Infinite Matrix Of Tamagotchis

November 24, 2015 by Brian Benchoff 45 Comments

Tamagotchi is a digital pet, living in and cared for through a key-chain size piece of hardware. The mid-90’s toy lives in pop culture, but now it lives well beyond. A limitless network of Tamagachi has been created using some amazing tricks to feed, socialize, and monitor the beast now known as the Tamagachi Singularity.

Last weekend at the Hackaday SuperConference we were graced with a talk by [Jeroen Domburg], a.k.a. [Sprite_tm]. [Sprite] is a favorite of ours and over the years his hacker cred includes everything from reverse engineering hard drive controller chips to putting video games in his keyboard.

[Sprite] is also something of an Architect, and like all Architects he only wants what is best for the system he created. In this case, it’s a Matrix of Tamagotchis. [Sprite] created a hive of Tamagotchis that are able to interact with each other in their own separate world. The best part about this Matrix? There’s no allusions to violating the laws of thermodynamics in the exposition.

Like all good hacks, a Tamagotchi Matrix wasn’t created in a vacuum. A few years ago at 29C3, [Natalie Silvanovich] dumped the ROM in the current generation of Tamagotchis. This is an incredible feat of reverse engineering, that allows anyone to use the full capabilities of the 6502-based microcontroller that controls these digital pets

After [Sprite] figured out how to read and run the code in the Tamagotchi, the next obvious step towards a world of egg-shaped pods containing an entire population of Tamagotchis is virtual Tamagotchis. [Sprite] used a hard-coded state machine that takes care of pooping, flushing, training, feeding, and turning the lights off at bedtime.

With a single Tamagotchi described as a state machine, it’s a simple matter to build another. This is where things get interesting and Matrix-ey. Tamagotchis don’t live alone; they have an IR LED and receiver that allows them to interact with each other, eat, play, marry, and have kids. Emulating a single Tamagotchi is one thing, but controlling multiples is another thing entirely; some sort of protocol was needed to breed Tamagotchis and keep them happy and well-fed.