Using librtlsdr Over TCP

[Texane] built a low-cost software defined radio rig which could be remotely controlled. This allows the hardware to be placed outside for better reception, while being controlled from any PC that can connect over TCP. To do this, he created a fork of librtlsdr, the library used to turn cheap TV tuners into software defined radios.

The official release of rtl-sdr includes the rtl_tcp utility, which is meant for this purpose. Unfortunately, not all of the SDR tools for Linux support this. By modifying the library itself, remote devices interact with software in the same way as local devices. This means that any software that supports librtlsdr should work.

The outdoor rig contains a BeagleBone Black and the SDR hardware, sealed up in a weather-resistant box. This connects to [Texane]’s home network over ethernet, and allows SDR utilities to be run elsewhere.

This feature is quite experimental, but the source for the fork is provided for those who want to build the code and try it out.

CircuitHub Launches Group Buy Crowdsourcing Campaigns

Kickstarter isn’t the solution to every manufacturing hurdle, you know? Crowdsourcing—everybody’s favorite cliché to invoke after sharing their less-than-half-baked merchandise idea—has expanded to include yet another variation, and is currently rocking [Max Thrun’s] BeagleBone GamingCape thanks to [Jason Kridner]. If the cape looks familiar, it’s because we featured it earlier this summer, when [Max] created it as part of TI’s Intern Design Challenge.

Here’s how it works. Rather than asking strangers to place pre-orders (let’s admit it, that’s ultimately how Kickstarter functions), CircuitHub campaigns work as a group-buy: upload your KiCad, Eagle or Altium design and a BOM, and you’re on your way to bulk-order savings. As [Kridner] explains in his blog post, you’ll have some finagling to do for your campaign to be successful, such as choosing between prices at different volumes, projecting how many people need to buy in as a group, etc. When he sourced the parts on his own, [Kridner] spent nearly $1000 for a single GamingCape. The CircuitHub campaign, if successful, would land everyone a board for under $100 each—and it’s assembled. 

Who needs Kickstarter; that’s hard to beat.

A Better Anonabox with the Beaglebone Black

A few weeks ago, Anonabox, the ill-conceived router with custom firmware that would protect you from ‘hackers’ and ‘legitimate governments’ drew the ire of tech media. It was discovered that this was simply an off-the-shelf router with an installation of OpenWrt, and the single common thread in the controversy was that, ‘anyone can build that. This guy isn’t doing anything new.’

Finally, someone who didn’t have the terrible idea of grabbing another off the shelf router and putting it up on Kickstarter is doing just that. [Adam] didn’t like the shortcomings of the Anonabox and looked at the best practices of staying anonymous online. He created a Tor dongle in response to this with a Beaglebone Black.

Instead of using wireless like the Anonabox and dozens of other projects, [Andy] is using the Beaglebone as a dongle/Ethernet adapter with all data passed to the computer through the USB port. No, it doesn’t protect your entire network; only a single device and only when it’s plugged in.

The installation process is as simple as installing all the relevent software, uninstalling all the cruft, and configuring a browser. [Adam] was able to get 7Mb/sec down and 250kb/sec up through his Tor-ified Ethernet adapter while only using 40% of the BBB’s CPU.

Delta Coffee-Brewing Bot

Pour-over coffee brewing is a simple and cheap hands-on alternative to using an automatic coffee maker. Although coffee aficionados often choose pour-over just for the manual brewing experience, this didn’t stop [Elias] from automating his pour-over coffee setup with an elaborate delta-robot: the DeBrew.

The coffee-brewing robot is built around a delta assembly from a 3d printer controlled by a BeagleBone Black. The BeagleBone drives stepper motors, displays information on a small open-source hardware HDMI LCD display, and serves up a web interface to control the machine. The radius of the pouring pattern, water temperature, and grind coarseness of the DeBrew can all be customized though its web interface.

For those who want to build their own pour-over robot, [Elias] has made a SketchUp drawing of the design and all of his Python source code available as open-source. Check out the video after the break where [Elias] explains how his delta pour-over bot works.

Continue reading “Delta Coffee-Brewing Bot”

Custom CAN System Logs Motorcyle Data like Magic

RW-2x_on_stand_at_TRC

A student team at Ohio State University has designed and built a custom Controller Area Network (CAN) data acquisition system complete with a sensor interface, rider display, and a Linux-based data logger for a RW-2x motorcyle.

They call their small, convenient micro-controller circuit board the Magic CAN Node, and it measures automotive sensors throughout the electric vehicle. This includes a variety of thermistor resistors to check changes in temperature. A few 0-5V and 0-12V sensors to monitor brake pressure transducers along with some differential air pressure sensors can be added too. Since the vehicle is basically a “rolling electromagnetic noise bomb”, they wanted to keep all of these analog sensors as close to the source as possible.

The Magic CAN Node is based on a Texas Instruments microcontroller called the TMS320F28035. This keeps the energy consumption at a low level.

For message handling, the team, led by [Aaron], tapped into the built-in CAN module within the F28035. All of the CAN plugs have two of the pins shorted to GND or +12V, so when there’s only one plug connected, the analog switch IC will connect a 120 ohm resistor across the CAN lines.

Continue reading “Custom CAN System Logs Motorcyle Data like Magic”

The CryptoCape For BeagleBone

[Josh Datko] was wandering around HOPE X showing off some of his wares and was kind enough to show off his CryptoCape to us. It’s an add on board for the BeagleBone that breaks out some common crypto hardware to an easily interfaced package.

On board the CryptoCape is an Atmel Trusted Platform Module, an elliptic curve chip, a SHA-256 authenticator, an encrypted EEPROM, a real time clock, and an ATMega328p for interfacing to other components and modules on the huge prototyping area on the cape.

[Josh] built the CryptoCape in cooperation with Sparkfun, so if you’re not encumbered with a bunch of export restrictions, you can pick one up there. Pic of the board below.

Continue reading “The CryptoCape For BeagleBone”

An Introduction To The BeagleBone PRU

BBB While the BeagleBone is usually compared to the Raspberry Pi, there are a few features that make the ‘Bone a vastly more capable single board computer. There is a small difference in the capabilities of the processor, but the real power of the BeagleBone comes from the PRUs available: two small cores that give the BeagleBone the hardware equivalent of bitbanging pins. [Texane] has put up two great tutorials for using the PRU in the BeagleBone that should be required reading for every BeagleBone owner.

The first tutorial goes over the capabilities of the PRUs in the BeagleBone and setting up the software environment to develop your own hardware interfaces with the PRU. While writing code for the PRU has usually involved the Beagleboard packages, TI has recently released a version of Code Composer Studio that gives the option to compile C code for the PRU.

[Texane] used this C compiler to rehash the earlier, assembly only PRU program, making development significantly easier. There’s still a bit of inline assembly, and the inline assembly support isn’t as advanced as in GCC, but it’s still much easier than the assembly only variant.

While [Texane] is using the PRU in his BeagleBone to develop something at a synchrotron facility, three are a few things where really fast hardware bitbanging comes in handy: it can be used to make a video card for a vintage mac, or any sort of VGA video card, really. Very cool stuff, especially now that you can write something in C.