Posts with «beaglebone black» label

Reverse Engineering the Smart ForTwo CAN Bus

The CAN bus has become a defacto standard in modern cars. Just about everything electronic in a car these days talks over this bus, which makes it fertile ground for aspiring hackers. [Daniel Velazquez] is striking out in this area, attempting to decode the messages on the CAN bus of his Smart ForTwo.

[Daniel] has had some pitfalls – first attempts with a Beaglebone Black were somewhat successful in reading messages, but led to strange activity of the car and indicators. This is par for the course in any hack that wires into an existing system – there’s a high chance of disrupting what’s going on leading to unintended consequences.

Further work using an Arduino with the MCP_CAN library netted [Daniel] better results, but  it would be great to understand precisely why the BeagleBone was causing a disturbance to the bus. Safety is highly important when you’re hacking on a speeding one-ton metal death cart, so it pays to double and triple check everything you’re doing.

Thus far, [Daniel] is part way through documenting the messages on the bus, finding registers that cover the ignition and turn signals, among others. Share your CAN hacking tips in the comments. For those interested in more on the CAN bus, check out [Eric]’s great primer on CAN hacking – and keep those car hacking projects flowing to the tip line!


Filed under: car hacks

Turning a toy piano into a standalone digital synthesizer

Electronic musical instruments are fun for Makers. With some cheap tools, know-how and passion, anyone can become a real synth geek. Just ask software developer Liam Lacey, who also happens to be a sound coder and freelance hacker. He recently won element14’s Open Source Music Tech design challenge for his Vintage Toy Synthesizer project — it’s an acoustic wooden toy piano converted into an open-source, standalone polyphonic digital synthesizer running on a BeagleBone Black and an Arduino Pro Mini.

Playing an instrument is about a lot more than just the sound you create – the way you play it; the physical feedback; and the overall feel and aesthetics of the instrument also play a big role in the overall experience, with these elements also helping to nurture inspiration, and can even affect your perception of the sound created.

Lacey developed the voice engine using the C++ audio DSP library Maximilian, and the keyboard mechanism uses homemade pressure sensors made out of Velostat. The instrument has 18 keys, with players able to also alter scales using the knobs on top of the mini piano’s lid.

Other dials are used to toggle dedicated waveform oscillators, various filters and onboard distortion effects, and there’s even vintage parameters for replicating old or broken analog synth voices. What’s neat is that the converted toy can also act as a MIDI controller to send velocity-sensitive note messages and polyphonic aftertouch to Logic Pro, Ableton Live and various music software programs.

Here’s a diagram of the software architecture of the synth:

You can read more about the hack here, as well as listen to some quick and rough sound/patch demos:

The project took three and a half months to bring to fruition, and let us just say, the final result is quite impressive! Check out the video below to learn more about  its specs and explore the complete documentation on GitHub.