Adafruit Feather

32 Articles

Adora-BLE Synth Wails Without Wires

February 29, 2020 by 4 Comments

Isn’t this the cutest little synth you ever saw? The matching sparkly half-stack amp really makes it, visually speaking. But the most interesting part? There’s not a wire in sight, ’cause [Blitz City DIY]’s futuristic rig sends the bleep boops over Bluetooth LE.

Hardware-wise, both the synth and the amp are fairly simple. Underneath each of those cute little printed keys is one of those clicky momentaries that usually come with bright button caps in primary colors — the keys themselves just press-fit over the tops. All twelve ebonies and ivories are connected up to an Adafruit Feather, which communicates over Bluetooth LE to a CircuitPlayground Bluefruit (CPB) in the amp. Each time a note is played on the synth, its corresponding color circles comet-like around the CPB’s NeoPixels, which shine through the amp’s speaker grille.

The super interesting part is that all the hard work is happening in the code. Both boards have the same array of colors in rainbow order, and the CPB has an array of tone frequencies that match up one for one with the colors. For every note played, the CPB looks up the color, swirls it, and plays the note. If you want to build one, this project is wide open — [Blitz City DIY] even made a learn guide with all the dirty details. Be sure to check out the demo and extended walk-through after the break.

More in the market for making a computer keyboard? Just grab the nearest ESP32.

Continue reading “Adora-BLE Synth Wails Without Wires” →

Arduino Handheld Game System Gets A Grip

February 6, 2020 by 7 Comments

With little more than an Arduino, an OLED display, and some buttons, it’s easy to build your own faux-retro game system. There’s even a growing library of titles out there that target this specific combination of hardware, thanks in no small part to the Arduboy project. But unless you’re content to play Circuit Dude on a breadboard, at some point you’ll probably want to wrap the build up in a more convenient form.

Like many that came before it, the OLED handheld created by [Alex Zidros] takes inspiration from a Nintendo product; but it’s not the Game Boy. Instead, his design is based on a 3D printed grip for the Switch Joy-Cons that he found on Thingiverse. After tacking on a holder for the PCB, he had the makings of a rather unique system.

We especially like the offset SSD1306 OLED display. Not because we think a game system with an asymmetrical layout is a particularly sound design decision, but because it gives the whole build a rather cyberpunk feel. When combined with the exposed electronics, the whole system looks like it could have been cobbled together from a futuristic dumpster. Which is high praise, as far as we’re concerned.

Opposite the display is a LiPo pouch battery that [Alex] says was liberated from a portable speaker, and down below is an Adafruit Feather 328P. There are two tactile switches mounted to the front of the Feather, and in something of a departure from these sort of builds, there are two more on the shoulders of the 3D printed case. Everything is held together with nothing more exotic than a scrap of perfboard, making it easy for anyone who might want to build their own version.

If you prefer your Arduino and OLED gaming to come in a slightly more familiar form factor, the build that was done inside of a Dreamcast Visual Memory Unit (VMU) has always been a favorite around these parts.

Winners Of The Take Flight With Feather Contest

January 22, 2020 by 10 Comments

It’s hard to beat the fidelity and durability of printed text on paper. But the e-paper display gets pretty close, and if you couple it will great design and dependable features, you might just prefer an e-reader over a bookshelf full of paperbacks. What if the deal is sweetened by making it Open Hardware? The Open Book Project rises to that challenge and has just been named the winner of the Take Flight with Feather contest.

This e-reader will now find its way into the wild, with a small manufacturing run to be put into stock by Digi-Key who sponsored this contest. Let’s take a closer look at the Open Book, as well as the five other top entries.

Continue reading “Winners Of The Take Flight With Feather Contest” →

A Pocket-Sized Terminal For Mobile Python Hacking

December 28, 2019 by 14 Comments

Inspired by the good old days when your computer would boot directly into BASIC, [Le Roux Bodenstein] has created a handheld device he calls “DumbDumb” that can drop you into a MicroPython environment at a moment’s notice. If that doesn’t interest you, think of it this way: it’s a (relatively) VT100 compatible serial terminal with a physical keyboard that can fit in your pocket.

Being essentially just a dumb terminal (hence the name), there’s actually not a lot of hardware on the board. Beyond the 320×240 NewHaven 2.4 inch LCD, there’s just an STM32G071R8 microcontroller and a handful of passives. Plus the 57 tactile buttons that make up the keyboard, of course.

The MicroPython part comes in thanks to the spot on the back of the board that accepts an Adafruit Feather Wing. In this case, it’s the HUZZAH32 with an ESP32 on board, but it could work with other variants as well. With the wide array of Feather boards available, this terminal could actually be used for an array of applications.

So even if fiddling around with MicroPython isn’t your idea of a good time, there’s almost certainly some interesting software you could come up with for a tiny network-attached terminal like this. For example, it might be just what you need to start working on that LoRa pager system.

Giant Analog CO2 Meter Sweeps Away Doubt

November 14, 2019 by 11 Comments

Most of us are aware that trees turn CO₂ into oxygen, but we’d venture to guess that many people’s knowledge of this gas ends there. Is it feast or famine out there for the trees? Who can say? We admire [rabbitcreek]’s commitment to citizen science because he’s so focused on making it easy for people to understand their environment. His latest offering, a giant analog CO₂ meter, might be our favorite so far.

The brains of the operation is an Adafruit Feather Adalogger. It reads the CO₂ sensor that’s mounted close to the business end of the nautilus, and becomes the quill that writes the CO₂ value to a FeatherWing e-ink screen. For the giant needle, this lovely meter uses one of those fiberglass poles you mark your driveway with so you can find it under a blanket of snow. The needle is counter-balanced with washers encased in printed plastic.

As you can see in the GIF, there’s a decent delay between the CO₂ blast and the needle response — we like to imagine the CO₂ spiraling slowly through the nautilus like a heavy, ill wind on its way to gravely move the needle.

Want a way to monitor air quality that’s a bit more discreet? Slip this portable meter into your pocket.

Building An Open Hardware EBook Reader

October 31, 2019 by 26 Comments

On the whole, hackers aren’t overly fond of other people telling them what they can and cannot do with the hardware or software they’ve purchased. Unfortunately, it’s becoming more and more difficult to avoid DRM and other Draconian rules and limitations as time goes on. Digital “eBooks” and the devices that are used to view them are often the subject of such scrutiny, which is why [Joey Castillo] has made it his mission to develop a open hardware eReader that truly belongs to the user.

[Joey] has been working on what he calls the “The Open Book Project” for a few months now, and he’s just recently announced that the first reader has been successfully assembled and powered up. As is usually the case, a few hardware issues were identified with this initial prototype. But it sounds like the device was largely functional, and only a few relatively minor tweaks to the board layout and components should be necessary before the hardware is ready for the masses.

An earlier prototype, using the Adafruit Feather

If you’re feeling a bit of déjà vu seeing this, don’t worry. The Open Book Project has taken a somewhat circuitous path to get to this first prototype, and [Joey] had previously developed and built the “eBook Feather Wing”. While they look very similar, that earlier incarnation required an Adafruit Feather to operate and was used to help refine the firmware and design concepts that would go into the final hardware.

The Open Book is powered by a ATSAMD51N19A processor with a GD25Q16 2MB flash chip to hold the CircuitPython code, and a microSD slot to store the actual book files. It also features support for audio output via a standard 3.5 mm headset jack, an RGB status LED, and expansion ports that tap into the I2C interface for adding whatever other hardware you can dream up.

One of the most interesting aspects of this Creative Commons licensed reader is the extensive self documentation [Joey] has included on the silkscreen. Every major component on the back of the PCB has a small description of its purpose and in some cases even a breakdown of the pin assignments. The idea being that it not only makes the device easier to assemble and debug, but that it can also explain to the curious user what everything on the board does and why it’s necessary. It’s a concept that makes perfect sense given the goals of the Open Book Project, and something that we frankly would love to see more of.

[Marc Juul] presented his work on a FOSS operating system for older-model Kindles at HOPE XII as a way to avoid Orwellian monitoring of the user’s reading habits, so it’s interesting to see somebody take this idea to the next level with completely libre reader hardware. Unfortunately none of this addresses the limited availability of DRM-free eBooks, but one step at a time.

Handheld LoRa Joystick For Long-Range Bots

September 11, 2019 by 11 Comments

Wanting a simple tool to aid in the development of LoRa controlled robotic projects, [Jay Doscher] put together this very slick one-handed controller based on the 900 MHz Adafruit Feather M0. With a single trigger and a miniature analog joystick it’s a fairly simple input device, but should be just enough to test basic functionality of whatever moving gadget you might find yourself working on.

Wiring for this project is about as simple as you’d expect, with the trigger and joystick hanging off the Feather’s digital ports. The CircuitPython code is also very straightforward, though [Jay] says in the future he might expand on this a bit to support LoRaWAN. The controller was designed as a barebones diagnostic tool, but the hardware and software in its current form offers an excellent opportunity to layer additional functionality on a known good base.

Everything is held inside a very well designed 3D printed enclosure which [Jay] ran off on his ELEGOO Mars, one of the new breed of low-cost resin 3D printers. The machine might be pretty cheap, but the results speak for themselves. While resin printing certainly has its downsides, it’s hard not to be impressed by the finish quality of this enclosure.

While LoRa is generally used for transmitting small bits of information over long distances, such as from remote sensors, this isn’t the first time we’ve seen it used for direct control of a moving object. If you’re not up to speed on LoRa, check out this excellent talk from [Reinier van der Lee] that goes over the basics of the technology and how he used it to build a community sensor network.