Spin Some Spudgers From Secondhand Silverware

February 12, 2022 by 20 Comments

Even though it’s not the right tool for the job, we’ve all used a flat head screwdriver for other purposes. Admit it — you’ve pried open a thing or two with that one in the toolbox that’s all dirty and dinged up anyway. But oftentimes, screwdrivers just aren’t thin enough. What you need is a spudger, which for some reason, seem to only come in plastic. Blame our disposable times.

In a relevant break from building electronics, [lonesoulsurfer] took the time to craft a set of spudgers and such from secondhand silverware. These are all made from spoons and butter knives sourced from a thrift store. For the spoons, [lonesoulsurfer] removed the heads with an angle grinder, shaped them on a belt sander, and thinned them out until they were spudger-slim. After doing the same with the handle end, [lonesoulsurfer] polished up the new tools on the wheel with some compound.

Not all of these are spudgers — some are destined to scrape, and others for lifting badges and decals. But they all live in harmony in a handy carrying case. Check out the build video after the break.

On the other hand, sometimes a disposable tool is all you really need.

Continue reading “Spin Some Spudgers From Secondhand Silverware” →

A pinout diagram of the new Pi 4, showing all the alternate interfaces available.

Did You Know That The Raspberry Pi 4 Has More SPI, I2C, UART Ports?

February 1, 2022 by 35 Comments

We’ve gotten used to the GPIO-available functions of Raspberry Pi computers remaining largely the same over the years, which is why it might have flown a little bit under the radar: the Raspberry Pi 4 has six SPI controllers, six I2C controllers, and six UARTs – all on its 40-pin header. You can’t make use of all of these at once, but with up to four different connections wired to a single pin you can carve out a pretty powerful combination of peripherals for your next robotics, automation or cat herding project.

The datasheet for these peripherals is pleasant to go through, with all the register maps nicely laid out – even if you don’t plan to work with the register mappings yourself, the maintainers of your preferred hardware enablement libraries will have an easier time! And, of course, these peripherals are present on the Compute Module 4, too. It might feel like such a deluge of interfaces is excessive, however, it lets you achieve some pretty cool stuff that wouldn’t be possible otherwise.

Having multiple I2C interfaces helps deal with various I2C-specific problems, such as address conflicts, throughput issues, and mixing devices that support different maximum speeds, which means you no longer need fancy mux chips to run five low-resolution Melexis thermal camera sensors at once. (Oh, and the I2C clock stretching bug has been fixed!) SPI interfaces are used for devices with high bandwidth, and with a few separate SPI ports, you could run multiple relatively high-resolution displays at once, No-Nixie Nixie clock style.

As for UARTs, the Raspberry Pi’s one-and-a-half UART interface has long been an issue in robotics and home automation applications. With a slew of devices like radio receivers/transmitters, LIDARs and resilient RS485 multi-drop interfaces available in UART form, it’s nice that you no longer have to sacrifice Bluetooth or a debug console to get some fancy sensors wired up to your robot’s brain. You can enable up to six UARTs. Continue reading “Did You Know That The Raspberry Pi 4 Has More SPI, I2C, UART Ports?” →

A wooden device with an LED display and speakers

The Inspirer Keeps Your Mood Up With Inspirational Quotes And Soothing Music

December 19, 2021 by 2 Comments

While some people enjoy the cold weather and long, dark nights in the Northern Hemisphere these days, others may find it hard to keep a positive mindset all through the winter. [Michael Wessel] decided he needed to do something about that and came up with The Inspirer, a desktop display that shows inspirational quotes and plays soothing music.

The design is deliberately bare-bones: a strip of wood, standing upright thanks to two metal brackets, onto which a bunch of components have been screwed, glued and taped. The actual display consists of a row of 14-segment LED modules that can show basic alphanumeric characters; these displays emit white light, but [Michael] added a red color filter in front to give them a more “retro” look.

This device is fully off-grid, so no Internet connection issues will disrupt your flow. A huge database of quotes and a selection of music tracks are stored on a pair of micro SD cards; an MP3 player module handles the music while an Arduino picks a quote, drives the display, and reads the buttons. You can select quotes based on a certain theme: examples include friendship, gardening, money, and love. But if you’re open to anything, you can just set it to “random” and get something from any of the 120 categories.

[Michael]’s simple and straightforward design should hopefully prove inspirational to many hardware enthusiasts. But if you’re looking for something more advanced, we featured a neat pomodoro timer that displays quotes a few weeks ago. Of course, this being Hackaday, we’ve also seen a clock based on literary quotes.

Continue reading “The Inspirer Keeps Your Mood Up With Inspirational Quotes And Soothing Music” →

USB LED Christmas Tree Is Making Spirits Bright

December 13, 2021 by 9 Comments

[Piotr SB] knows there is no way out of the holidays; the only path is through. You’ve got to find cheer wherever and however you can, so why not cater to your own interests and build the cutest little LED Christmas tree you ever did see? And did we mention it’s USB and absolutely free (as in carols, not eggnog)?

This O-Christmas tree is made up of concentric rings that are built into a tier as you solder the LEDs. And of course you’re supposed use the LED legs as supports! One leg from each LED — 18 green and a red one for the top. Because the PCB is not quite thick enough, you’ll need to add a plastic spacer to get it to stay in the USB port. Not only is this a nice design, the snowflakes and snowman on the silkscreen totally seal the cuteness deal.

Ever get so frustrated with your Christmas tree that you want to just empty a few rounds into the thing? No? Well, you’d have a good reason to if you built this Duck Hunt ornament.

Arduino Drives Faux Spirograph

December 10, 2021 by 11 Comments

The holidays always remind us of our favorite toys from when we were kids. Johnny Astro, an Erector set, and — of course — a Spirograph. [CraftDiaries] has an Arduino machine that isn’t quite a Spirograph, but it sure reminds us of one. The Arduino drives two stepper motors that connect to a pen that can create some interesting patterns.

The build uses a few parts that were laser cut, but they don’t look like they’d be hard to fabricate using conventional means or even 3D printing. The author even mentions you could make them out of cardboard or foamboard if you wanted to.

Continue reading “Arduino Drives Faux Spirograph” →

Hackaday Podcast 147: Animating Traces, Sucking And Climbing, Spinning Sails, And Squashing Images

December 3, 2021 by 2 Comments

Hackaday editors Mike Szczys and Elliot Williams get caught up on the week that was. You probably know a ton of people who have a solar array at their home, but how many do you know that have built their own hydroelectric generation on property? Retrocomputing software gurus take note, there’s an impressive cross-compiler in town that can spit out working binaries for everything from C64 to Game Boy to ZX Spectrum. Tom took a hard look at the Prusa XL, and Matthew takes us back to school on what UEFI is all about.

Take a look at the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!

Direct download (55 MB)

Where to Follow Hackaday Podcast

Places to follow Hackaday podcasts:

Continue reading “Hackaday Podcast 147: Animating Traces, Sucking And Climbing, Spinning Sails, And Squashing Images” →

LEDs display different pitches in a sunburst pattern

Spiral Music Visualization

November 26, 2021 by 6 Comments

Displaying notes live as they are being played can be a really powerful learning tool, but it’s usually used to learn how to play a specific instrument. This take on the topic is actually a neat way to learn more about music theory — how pitches work together to build the sounds that we hear. The visual tack chosen arranges each of 12 notes into a spiral. As you continue to go up the scale through more octaves, pitches that share the same name line up into a line like a ray projecting out from the sun. So there are 12 rays for the notes in the scale: C, C#/D♭, D, D#/E♭,F, etc.

[mechatronicsguy] built it a few years back but just now got around to documenting it, and we’re sure glad he did. The layout of notes at first looks just like a colorful visualization. But as he mentions in his description, this assigns a shape to each different type of cord. A major cord will have the same shape whether it is played with C, G#, B♭, or any other note as the root. The shape simply rotates around the axis based on that root note. Higher octaves will be shown further out on the radius, but the chord shape will still be the same. Minor, augmented, even modal chords and those with added pitches all have their own unique shape on the display.

You get the best understanding of the visualization by looking at the Python-rendered version in the video below. It’s a nice touch that notes turn grey and fade away after being released so you kind of see where the current chord came from. This isn’t strictly a perk of pre-recordings. While you can feed it MIDI files, you can also play a MIDI instrument and display the visuals live on the hardware version that uses a Teensy with an audio shield.

If you’re looking for examples on how music visualizers are used to teach the instrument, look no further than this Wurlitzer note visualizer replica. Also for those who don’t know, the song being played in the hardware demo (second video below) is Beethoven’s 7th Symphony. Well worth a full listen, it’ll change your life.

Continue reading “Spiral Music Visualization” →