Raspberry Pi

1836 Articles

Zelda And The Ocarina Of Things

March 20, 2017 by 21 Comments

Voice recognition is this year’s model for home automation, but aside from feeling like you’re onboard the Aries 1b arguing with HAL 9000, it just doesn’t do it for our geeky selves. So what’s even geekier? How about carrying around an ocarina in your pocket so that you can get a Raspberry Pi to unlock the door for you? (YouTube video, embedded below.) Yeah, that’ll do.

[Sufficiently Advanced]’s video gets us 90% of the way toward replicating this build. There’s a tube with a microphone and a Raspberry Pi inside. There are a bunch of ESP8266-powered gadgets scattered around the house that take care of such things as turning on and off the heater, watering plants, and even pressing a (spare) car remote with a servo.

We’d love to know what pitch- or song-recognition software the Raspberry Pi is running. We’ve wanted to implement a whistling-based home automation interface since seeing the whistled. We can hold a tune just fine, but we don’t always start out on the same exact pitch, which is a degree of freedom that [Sufficiently Advanced]’s system doesn’t have to worry about, assuming it only responds to one ocarina.

If you’re questioning the security of locking and unlocking your actual apartment by playing “Zelda’s Lullaby” from outside your window, you either overestimate the common thief or you just don’t get the joke. The use case of calling (and hopefully finding) a cell phone is reason enough for us to carry a bulky ocarina around everywhere we go!

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The Best Pi Emulation Console You Can Build

March 19, 2017 by 16 Comments

By far the most popular use for a Raspberry Pi is an emulation console. For an educational device, that’s fine – someone needs to teach kids how to plug a USB cable into a device and follow RetroPi tutorials on the Internet. These emulation consoles usually have one significant drawback: they’re ugly, with wires spilling everywhere. Instead of downloading a 3D printed Pi enclosure shaped like a Super Nintendo, [depthperfection] designed his own. It looks great, and doesn’t have a donglepocalypse hanging out the back.

The biggest factor in building an enclosure for a Pi Zero is how to add a few USB ports. There’s only one USB port on the Pi Zero, although if you’re exceptionally skilled, you can solder a hub onto the test points on the bottom of the board. This stackable USB hub solves the problem with the help of pogo pins for the power and USB pair. It’s only $17 USD, too.

With the USB and power sorted, [depthperfection] set out to design an enclosure. This was modeled in Fusion360, with proper vent holes, screw bosses, and cutouts for all the ports. It’s designed to be 3D printable, and with a little ABS smoothing, this enclosure looks great.

For software, [depthperfection] turned to Recallbox, a retrogaming platform that also doubles as a media player. It’s simpler than a RetroPi installation, but for playing Super Mario 3, you don’t really need many configuration options. This is a great project that just works and looks good doing it. The world — and the Raspberry Pi community — needs more projects like this, and we’re glad [depthperfection] sent this one in.

PiSound, The Audio Card For The Raspberry Pi

March 16, 2017 by 40 Comments

Kids today are being loud with their ‘drum machines’ and ‘EDM’. Throw some Raspberry Pis at them, and there’s a need for a low-latency sound card with MIDI and all the other accouterments of the modern, Skrillex-haired rocker. That’s where PiSound comes in.

Of course, the Pi already comes with audio out, but that’s not enough if you want to do some real audio processing. You need audio in as well, and while you’re messing around with that, adding some high-quality opamps, ADCs, DACs, and some MIDI would be a good idea. This is what the PiSound is all about.

[Pranciskus], the guy who has been working on the PiSound for a while now, developed this multitool for audio on a tiny Linux system. One of the killer features on the PiSound is ‘The Button’, a simple tact switch that runs a script if the button is pressed, another script if the button is held down, and two more if the button is pressed two or three times. This is actually a pretty nifty UI, and we wouldn’t mind seeing this on a few more Pi accessories.

If you’d like to see some example projects using the PiSound, there example MIDI controllers, networked audio players, and some goofing around with LV2 plugins over here.

Super Computing With Mini ITX Cluster

March 16, 2017 by 16 Comments

[Colin Alston] was able to snag a handful of Mini ITX motherboards for cheap and built a mini super computer he calls TinyJaguar. Named partly after the AMD Sempron 2650 APU, the TinyJaguar boasts four, yes that’s four MSI AM1I Mini-ITX motherboards, each with 4GB of DDR memory.

A Raspberry Pi with custom software manages the cluster, and along with some TTL and relays, controls the power to the four nodes. The mini super computer resides in a custom acrylic case held together by an array of 3D printed parts and fasteners.There’s even a rack-like faceplate near the bottom to host the RPi, an Ethernet switch, an array of status LEDs, and the two buttons.

With 16 total cores of computing power (including GPU), the TinyJaguar is quite capable of doing some pretty cool stuff such as running Jupyter notebook with IPyParallel. [Colin] ran into some issues getting the GPU to behave with PyOpenCL. It took a bit of pain and time, but in the end he was able to get the GPUs up, and wrote a small message passing program to show two of the cores were up and working together.

Be sure to check out [Colin’s] super computer project page, specifically the ten project logs that walk through everything that went into this build. He also posted his code if you want to take a look under the hood.

Raspberry Pi Hitches Ride Inside Vintage Terminal

March 13, 2017 by 41 Comments

When a dumpster dive yielded a vintage video display terminal, [dennis1a4] knew just what to do — bring the Heathkit H19 back to life and stuff a Raspberry Pi inside.

The early days of the personal computer era were a time of great market diversity. Everyone was making stuff needed to cobble together your perfect computer, and terminals were among the most important pieces of gear. Lear Siegler, DEC, Wyse — everyone was in on the game. Even Heathkit competed with its H19 serial terminal, which would have set you back a thousand or so early-1980s dollars.

The terminal [dennis1a4] found was DOA, but he quickly determined that a bad cap was shorting out the -12VDC rail. A little extra detective work was needed to get the terminal to both echo characters locally and output them over the RS-232 port, and bam, working terminal. But then what? Raspberry Pi to the rescue! But those old school +/-12 volts swings would give a Pi a bad case of Blue Smoke Disease. After a little voltmeter poking, and through the magic of socketed driver chips, the Pi was talking right to the terminal at a screaming 9600 baud and accessing the Hackaday Retro site on the 80-by-24 mono display.

All in all, a nice hack on a piece of computer history. But just one question: Can it play Doom Flappy Bird?

Q Has Nothing On Naomi Wu

March 12, 2017 by 185 Comments

We’re not so much fans of James Bond as we are of Q, the hacker who supplies him with such wonderful things. There is a challenger to Q’s crown, [Naomi Wu] — code name [SexyCyborg] — built an epic gadget called the Pi Palette which hides a Linux laptop inside of a cosmetics case.

You can see the covert mode of the Pi Palette below. It resembles a clamshell cosmetics case with the makeup and applicator in the base and a mirror on the underside of the flip-up lid. The mirror hides an LCD screen in the portrait orientation, as well as a Raspberry Pi 3 running Kali Linux.

The base of the case includes a portable battery beneath the wireless keyboard/touchpad — both of which are revealed when the cosmetics tray is removed. An inductive charger is connected to the battery and [Naomi] built a base station which the Pi Palette sits in for wireless charging.

She envisions this as a covert penetration testing. For that, the Pi Palette needs the ability to put the WiFi dongle into promiscuous mode. She wired in a dual dip-switch package and really went the extra mile to design it into the case. The fit and finish of that switch is just one tiny detail the illustrates the care taken with the entire project. With such a beautiful final project it’s no wonder she took to the streets to show it off. Check that out, as well as the build process, in the video after the break.

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Raspberry Pi-Based Game Boy Emulator

March 12, 2017 by 14 Comments

The most popular use for a Raspberry Pi, by far, is video game emulation. We see this in many, many forms from 3D printed Raspberry Pi cases resembling the original Nintendo Entertainment System to 3D printed Raspberry Pi cases resembling Super Nintendos. There’s a lot of variety out there for Raspberry Pi emulation, but [moosepr] is taking it to the next level. He’s building the smallest Pi emulation build we’ve ever seen.

This build is based on the Pi Zero and a 2.2″ (0.56 dm) ili9341 TFT display. This display has a resolution of 240×320 pixels, which is close enough to the resolution of the systems the Pi Zero can emulate. The Pi Zero and display are attached to a beautiful purple breakout board (shared on OSH Park) along with a few 5-way nav switches, a charger for a Lipo battery, and a few other bits and bobs.

Right now, [moosepr] is experimenting with adding sound to his board. It’s easy enough to get sound out of a Pi Zero — it’s just PWM coming from a few pins — but audio also needs an amp, a speaker, and more space on the board. To solve this problem, [moose] found a few piezo transducers from musical greeting cards. These are designed to be thin and as loud as possible, and attaching these directly to the PWM pins providing audio might just work. This is a project to keep an eye on, if only to see if cheap piezos work for low-fi audio in retro emulators.