Homebrew Retro Console Runs On PIC32

January 13, 2025 by Zoe Skyforest 9 Comments

[Chad Burrow] decided to take on a noble task—building a “retro” style computer and video game console. Only, this one is built using somewhat modern hardware—relying on the grunt of the PIC32MZ2048EFH144 to get the job done. Meet the Acolyte Hand PIC’d 32.

It’s name might be a mouthful, but that chip can pull off some great feats! With a clock speed of 200 MHz, it’s not short on processing power, though RAM and flash storage are somewhat limited at just 512 KB and 2MB respectively. [Chad] was able to leverage those constraints to get a VGA output working at a resolutions up to 800 x 600, with up to 65,000 colors—though 256 colors is more practical due to memory concerns. The Acolyte Hand also rocks two 8-bit audio channels. It has a pair of Genesis-compatible controller ports as well as PS/2 and USB for keyboards and mice, along with more modern Xbox 360 controllers.

[Chad] cooked up some software to put it through its paces, too. It’s got a Tetris clone on board, and can also run Game Boy games at full speed via the Peanut-GB emulator. That provides for a pretty rich game library, though [Chad] notes he plans to develop more native video games for his system to demo at his local college. Design files are on Github for the curious.

This project is a great example of just how powerful modern microcontrollers have become. Once upon a time, just driving a simple black-and-white graphical LCD might have taken some real effort, but today, there are pixels and clock cycles to spare in projects like these. Truly a wonderous world we live in!

Electromechanical 7-Segment Display Is High Contrast Brilliance

January 13, 2025 by Zoe Skyforest 11 Comments

The seven-segment display is most well known in LED form, but the concept isn’t tied to that format. You can build a seven-segment display out of moving parts, too. [tin-foil-hat] has achieved just that with a remarkably elegant design.

As you might expect, the build relies heavily on 3D-printed components—produced in white and black plastic to create a high-contrast display. It’s a simple choice that makes the display easy to read in a wide variety of lighting conditions, and far less fussy than toying with LEDs and diffusers and all that.

Actuation of each display segment is achieved electromagnetically. Effectively, each segment behaves like a flip dot, with the orientation controlled by energizing one of two electromagnets per segment. Controlling the electromagnets is an ESP32, which is hooked up to the various segments via a Darlington transistor array, with multiplexing used to minimize the number of IO pins required. A shift register was also employed to let the microcontroller easily drive four of these electromechanical digits.

It’s a simple build, well explained—and the final result is aesthetically pleasing. We’ve seen a few builds along these lines before, albeit using altogether different techniques. Lots of different techniques, in fact! Video after the break.

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How Nyan Cat Was Ported To UEFI

January 13, 2025 by Zoe Skyforest 13 Comments

The Unified Extensible Firmware Interface (UEFI) took over from the classical BIOS some years into the new millenium. It’s typically used for running a computer at the basic pre-OS level, and most of us don’t even notice it past boot time. However, you can do some neat things in this space—you can even port over Nyan Cat if you’re talented like [Cornelius].

*That’s fun. Set your friend’s computer to boot into this instead of their OS by default and see how long it takes them to figure it out.*

Yes, Nyan Cat is now available as a UEFI application, running via the EFI Simple Text Output Protocol. [Cornelius] approached this creation by first learning Rust, before progressing to the Hello World stage. Before long, the computer was booting up to display a simple text message with no OS required.

From there, creating the Nyan Cat animation required figuring out how to display it as a bunch of dancing characters, which is where the Simple Text Output Protocol came in. Nyan Cat was really the perfect animation for the UEFI environment, since its simple pixel art style was easily recreated with text. With a bit of work, the animation came together, with a remarkable resemblance to the original artwork.

All that’s missing is a routine to play the music over a PC speaker; only, those are hardly a thing anymore. A pity! In any case, if you’ve been cooking up your own nifty UEFI hacks, don’t hesitate to drop us a line!

Using Audio Hardware To Drive Neopixels Super Fast

January 13, 2025 by Zoe Skyforest 17 Comments

Here’s the thing about running large strings of Neopixels—also known as WS2812 addressable LEDs. You need to truck out a ton of data, and fast. There are a dozen different libraries out there to drive them already, but [Zorxx] decided to strike out with a new technique—using I2S hardware to get the job done.

Microcontrollers traditionally use I2S interfaces to output digital audio. However, I2s also just happens to be perfect for driving tons of addressable LEDs. At the lowest level, I2S hardware is really just flipping a serial data line really fast with a clock line and a word select line for good measure. If, instead of sound, you pipe a data stream for addressable LEDs to the I2S hardware, it will clock that data out just the same!

[Zorxx] figured that at with an ESP32 trucking out I2S data at a rate of 2.6 megabits per second on the ESP32, it would be possible to update a string of 256 pixels in just 7.3 milliseconds. In other words, you could have a 16 by 16 grid updating at over 130 frames per second. Step up to 512 LEDs, and you can still run at almost 70 fps.

There’s some tricks to pulling this off, but it’s nothing you can’t figure out just by looking at the spec sheets for the WS2812B and the ESP32. Or, indeed, [Zorxx’s] helpful Github page. We’ve featured some other unorthodox methods of driving these LEDs before, too! Meanwhile, if you’ve got your own ideas on how to datablast at ever greater speeds, don’t hesitate to let us know!

Camera Slider Uses Repositionable Rail To Do Rotational Moves

December 23, 2024 by Zoe Skyforest 2 Comments

You can buy motorized camera sliders off-the-shelf, but they’re pretty costly. Alternatively, you can make one yourself, and it’s not even that hard if you’re kitted out with a 3D printer. [Creative 3D Printing] did just that with a nifty design that adds rotation into the mix. Check it out in the video below.

Why should a camera get all the fun? Try your phone.

The basic slider is built out of 3D-printed components and some good old aluminum extrusion. A small 12-volt motor trucks the camera cart back and forth using a leadscrew. It’s torquey enough and slow enough that there isn’t much need for more advanced control—the motor just does the job. There’s also a limit switch set up to trigger a neat auto-reverse function.

The neat part, though, is the rotational mechanism. A smooth steel rod is attached to the slider’s housing, which can be set up in a straight line or aligned diagonally if desired. In the latter case, it rotates the mounting on the camera cart via a crank, panning the camera as it moves along the slider’s trajectory.

It’s a mechanically sophisticated design and quite unlike most of the camera sliders we feature around these parts.

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E-Paper Anniversary Counter Is A Charming Gift With Minimal Power Draw

December 23, 2024 by Zoe Skyforest 11 Comments

[Lonyelon] wanted to build an anniversary gift for his girlfriend. He decided to say it with e-Paper, a wise choice given its persistence and longevity.

The project is an anniversary calendar. It displays a counter of the total time the couple has been together, measured in years, months, days, and hours—so it’s remarkably precise. [Lonyelon] also programmed it to display additional counters to create plenty of additional fun anniversaries—the couple can celebrate milestones like their 1000th day together, for example. It also cycles through a range of cute messages and displays photos of the couple together.

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DIY Camera Slider Moves And Rotates For Slick Shots

December 22, 2024 by Zoe Skyforest 14 Comments

Camera sliders are a popular project for makers—especially those who document their projects on video. They’re fun and accessible to build, and they can really create some beautiful shots. [Lechnology] set about to follow in this fine tradition and built a rather capable example of his own. Check it out in the video below.

The slider relies on V-slot rails, perhaps most familiar for their heavy use in modern 3D printers. The rails are paired with a 3D-printed camera carriage, which runs on smooth rubber rollers. A chunky stepper motor provides drive via a toothed belt. Trinamic motor controllers were chosen for their step interpolation feature, making the motion much smoother.

The slider doesn’t just move linearly, either. It can rotate the camera, too, since it has an additional motor in the carriage itself. In a nice retro touch, the wires for this motor are run with an old coiled telephone cable. It’s perfect for the job since it easily extends and retracts with the slider’s motion. Controlling everything is an Arduino, with speed and rotational modes set via a tiny screen and a rotary encoder control.

It’s a very complete build, and it performs well too. The video it produces is deliciously smooth. We’ve featured some other great camera sliders over the years, too. If you want to dig into Trinamic drivers, we can get you started.

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