BeagleBone Green, Now Wireless

May 21, 2016 by 31 Comments

Over the past few years, the BeagleBone ecosystem has grown from the original BeagleBone White, followed two years later by the BeagleBone Black. The Black was the killer board of the BeagleBone family, and for a time wasn’t available anywhere at any price. TI has been kind to the SoC used in the BeagleBone, leading to last year’s release of the BeagleBone Green, The robotics-focused BeagleBone Blue, and the very recent announcement of a BeagleBone on a chip. All these boards have about the same capabilities, targeted towards different use cases; the BeagleBone on a Chip is a single module that can be dropped into an Eagle schematic. The BeagleBone Green is meant to be the low-cost that plays nicely with Seeed Studio’s Grove connectors. They’re all variations on a theme, and until now, wireless hasn’t been a built-in option.

This weekend at Maker Faire, Seeed Studio is showing off their latest edition of the BeagleBone Green. It’s the BeagleBone Green Wireless, and includes 802.11 b/g/n, and Bluetooth 4.1 LE.

Continue reading “BeagleBone Green, Now Wireless” →

BeagleBone Pin-Toggling Torture Test

April 21, 2016 by 20 Comments

Benchmarks often get criticized for their inability to perfectly model the real-world situations that we’d like them to. So take what follows in the limited scope that it’s intended, and don’t read too much into it. [Joonas Pihlajamaa]’s experiments with toggling a hardware pin as fast as possible on different single-board computers can still show us something.

The take-home result won’t surprise anyone who’s worked with a single-board computer: the higher-level interfaces are simply slow compared to direct memory-mapped GPIO access. But really slow. We’re talking around 5 kHz from Python or any of the file-based interfaces to the pins versus 3 MHz for direct access. Worse, as you’d expect when a non-realtime operating system is in the middle, there are glitches on the order of ten milliseconds with all the file-based methods.

This test only tells us so much, though, and it’s not really taking advantage of the BeagleBone Black’s ace in the hole, the PRUs — onboard hardware processors that bring real-time IO capabilities to the system. We’d like to see a re-write of the code to take advantage of libpruio, for instance. A 20 MHz square wave is a piece of cake with the PRUs.

Of course, it’s not interacting, which is probably in the spirit of the benchmark as written. But if raw hardware speed on a BeagleBone is the goal, it’s likely that the PRUs are going to feature prominently in the solution.

Bela: Real-Time BeagleBone Audio/Analog Cape

April 13, 2016 by 16 Comments

Bela is a cape for the BeagleBone Black that’s aimed at artists and musicians. Actually, the cape is much less than half of the story — the rest is in some clever software and a real-time Linux distribution. But we’re getting ahead of ourselves. Let’s talk hardware first.

First off, the cape has stereo input and output as well as two amplified speaker outs. It can do all of your audio stuff. It also has two banks of analogue inputs and outputs, each capable of handling eight signals. In our opinion, this is where the Bela is cool. In particular, the analog outputs are not Arduino-style “analog outputs” where it’s actually a digital output on which you can do PWM to fake an analog signal. These are eight 16-bit outputs from an AD5668 DAC which means that you can use the voltages directly, without filtering.

Then there’s the real trick. All of these input and output peripherals are hooked up to the BeagleBone’s Programmable Realtime Units (PRUs) — a hardware subsystem that’s independent of the CPU but can work along with it. The PRU is interfaced with the real-time Linux core to give you sub-microsecond response in your application. This is a big deal because a lot of other audio-processing systems have latencies that get into the tens of milliseconds or worse, where it starts to be perceptible as a slight lag by humans.

The downside of this custom analog and audio I/O is that it’s not yet supported by kernel drivers, and you’ll need to use their “Heavy Audio Tools” which compiles Pd programs into C code, which can then drive the PRUs. Of course, you can write directly for the PRUs yourself as well. If you just want to play MP3s, get something you have a bunch of simpler, better options. If you need to do responsive real-time audio installations, Bela is a way to go.

The project is open-source, but we had to do a bunch of digging to find what we were looking for. The hardware is in zip files here, and you’ll find the software here. The demo projects look/sound pretty cool and their Kickstarter is long over-funded, so we’re interested to see what folks make with these.

BeagleBone Green Hands-On: Lower Price, Same Horsepower

August 5, 2015 by 68 Comments

Although the BeagleBone Green was announced at the Bay Area Maker Faire last May, there hasn’t been much said about it on the usual forums and IRC channels. Now, it’s finally out and I got my hands on one of them. Through a cooperation between the BeagleBoard foundation and Seeed Studios, the best small Linux board for doing real work with small Linux boards is now cheaper, a little more modern, and green.

The BeagleBone Green is an update to the venerable BeagleBone Black, the dev board based on a TI ARM Cortex-A8. It’s an extremely capable machine with a few interesting features that make it the perfect device for embedded applications. With the BeagleBone Green, the BB Black gets a small hardware refresh and a drastic reduction in price. If you want to do real work on a Linux board, this is the one to get. Check out the review below for everything that’s been updated, everything that’s the same, and why this is one of the most interesting developments in small Linux boards in recent memory.

Continue reading “BeagleBone Green Hands-On: Lower Price, Same Horsepower” →

BeagleBones And Teensies Become KVMs

June 25, 2015 by 41 Comments

[pmf], like most of us, I’m sure, spends most of his days on a computer. He also has a smartphone he keeps at his side, but over the years he’s grown accustomed to typing on a real keyboard. He came up with the idea of making a USB switch that would allow his keyboard to control either his computer or his phone, and hit upon a really neat way of doing it. He’s using a BeagleBone Black and a Teensy to switch his keyboard between his computer and his phone with just a press of a button.

This homebrew smart KVM uses a BeagleBone Black for most of the heavy lifting. A keyboard and mouse is connected to the USB host port of the BeagleBone, and the main computer is connected to the device port. The BeagleBone is set up to pass through the USB keyboard and mouse to the computer with the help of what Linux calls a ‘gadget’ driver. This required an update to the Linux 4.0 kernel.

With the BeagleBone capable of being a USB pass through device, the next challenge was sending keypresses to another USB device. For this, a Teensy 2.0 was connected to the UART of the BeagleBone. According to [pmf], this is one of the few examples of the Teensy serving as a composite USB device – sending both keyboard and mouse info.

There are a few neat features for [pmf]’s build: the keyboard and mouse don’t disconnect when switching, and thanks to a slight modification of the USB OTG adapter, this will also charge a phone as well as allow for the use of a keyboard. Because the BeagleBone Black has more than one UART this build can also switch keyboards and mice between more than two computers. For those of us who invest heavily in keyboards, it’s a godsend.

Hacklet 35 – BeagleBone Projects

February 20, 2015 by 7 Comments

The Raspberry Pi 2 is just barely a month old, and now that vintage console emulation on this new hardware has been nailed down, it’s just about time for everyone to do real work. You know, recompiling stuff to take advantage of the new CPU, figuring out how to get Android working on the Pi, and all that good stuff that makes the Pi useful.

It will come as no surprise to our regular readers that there’s another board out there that’s just as good in most cases, and in some ways better than the Pi 2. It’s the BeagleBone Black, and for this edition of the Hacklet, we’re focusing on all the cool BeagleBone projects on Hackaday.io.

lcdSo you have a credit card sized Linux computer and a small, old LCD panel. If it doesn’t have HDMI, VGA or composite input, there’s probably no way of getting this display working, right? Nope. Not when you can make an LCD cape for $10.

[Dennis] had an old digital picture frame from a while back, and decided his BeagleBone needed a display. A few bits of wire and some FPC connectors, and [Dennis] has a custom display for his ‘Bone. It’s better than waiting for that DSI display…

bed[THX1082] is making a bed for his son. This isn’t your usual race car bed, or even a very cool locomotive bed. No, this is a spaceship bed. Is your bed a space ship? No, I didn’t think so.

Most of the work with plywood, MDF, paint, and glue is done, which means the best feature of this bed – a BeagleBone Black with an LCD, buttons, a TV, and some 3D printed parts – is what [THX] is working on right now. He’s even forking a multiplayer networked starship simulator to run in the bed. Is your bed a starship simulator?

beer

Beer. [Deric] has been working on a multi-step fermentation controller using the BeagleBone Black. For good beer you need to control temperatures and time, lest you end up with some terrible swill that I’d probably still drink.

This project controls every aspect of fermentation, from encouraging yeast growth, metabolization of sugars, and flocculation. The plan is to use two circuits – one for heating and one for cooling – and a pair of temperature sensors to ensure the beer is fermenting correctly.

If you’re looking for more BeagleBone Projects, there’s an entire list of them over on Hackaday.io with GLaDOs Glasses, Flight Computers, and Computer Vision.

Library Upgrade To PRU Gives Fast IO On Beaglebone

February 16, 2015 by 19 Comments

The BeagleBone Black has a powerful featureset: decent clock speed, analog inputs, multiple UART, SPI and I2C channels and on-board memory, to name a few. One missing feature seems to be the lack of support for the two on-board Programmable Real-time Units (PRU’s). Each of these 32-bit processors run independently of the main processor, but are able to interface with the main processor through the use of shared RAM and some interrupts. Unfortunately, PRU’s are not supported and in the absence of information, difficult to program. Enabling the PRU’s will allow them direct access to external sensors via the GPIO pins, for example. Perhaps most enticing is the idea that the PRU’s add real-time processing capability to the BBB.

[Thomas Freiherr] is working on the libpruio project to allow PRU support on the BBB. It is “designed for easy configuration and data handling at high speed. libpruio software runs on the host (ARM) and in parallel on a Programmable Realtime Unit SubSystem (= PRUSS or just PRU) and controls the subsystems”. Additional information about the project is available on the libpruio wiki, and files can be downloaded from here (German Page).

This paper presented at inter.noise2014 (PDF) a couple of months ago has a nice comparison of various small computer/controller boards and outlines the advantages of the BBB once its PRUs are enabled. If readers come across applications of the BBB with PRUs enabled, let us know in the comments. If you want to work your way into the world of the PRU we highly recommend this tutorial series.

Thanks for sending in the tip, [Patrick]

[Image Source: libpruio stepper motor example]