Teensy Adds S/PDIF To Library

June 9, 2015 by 35 Comments

With Arduino library support on an ARM Cortex M4 processor, it’s no surprise that we’re fans of the Teensy 3.1. And lately, [Paul Stoffregen] has been building out the Audio Library for this platform, making it even more appealing to the synth / audio geeks among us. And now, with just the addition of a highfalutin LED and some software, the Teensy can output digital audio over optical fiber.

S/PDIF, and more specifically optical TOSLINK, uses LED light sent down an optical fiber to encode audio data. The advantage of this over any voltage-level signals (like with regular wires) is that the source and destination devices aren’t electrically connected at all, which gets rid of the dreaded ground loop hum and any RF interference.

An S/PDIF audio data stream is a bit complex, but if you’re interested [Micah Scott] has a fantastic dissection of it up on her blog. Of course, you don’t have to know anything about any of that to simply use S/PDIF with the Teensy Audio Library.

We love open source hardware and software because of the collaborations that make ultra-rapid development of niche stuff like this possible. You can follow along with the development of the Teensy’s S/PDIF capabilities on the PJRC forum. Contributor [Frank B] modestly claims that “everything was already on the internet”, but that doesn’t make it any less cool that they got from zero to working library in a few weeks. (And note the clever use of a precomputed lookup table for speed.)

LED_TOSLINK2On the hardware side, [Paul] has posted up his adapter board for a cheap, but very professional looking, optical TOSLINK sender. But if you’re feeling ghetto, you can simply use a red LED pointed just right into the optical cable.

The end result? Lossless transmission of CD-quality audio from an Arduino-esque microcontroller, sent on a beam of light, for less than the cost of a latté.

We Have A Problem: 3D Printers Are Too Expensive

June 9, 2015 by 219 Comments

Hackaday, we have a problem. 3D printing is changing the world but it’s still too expensive to be embraced as a truly transformative technology.

With each passing year, the 3D printing industry grows by leaps and bounds. Food safe PLA is now the norm, with dissolvable and other exotic filaments becoming more mainstream.  New filaments are making it possible to print objects that were not possible before. New CAD software is popping up like dandelions, with each iteration giving novice users a friendly and more intuitive interface to design 3D models. As time marches on, and we look into its future, a vision of the 3D printing world is evident – its only going to get bigger.

3d printerImagine a future where a 3D printer is as common as an ink jet printer in homes all across the world.  A future where you could buy filament from the supermarket down the street, and pick up a new printer from any hardware store. A future where dishwashers, refrigerators and bicycles come with .stl files that allow you to print upgrades or spare parts. A future where companies compete to give the market easy-to-use printers at the cheapest price.

Is this future possible? Not until the technology changes. It’s too expensive, and that’s the problem you’re going to solve. How can you make a 3D printer cheaper? A cheap printer could change the game and make our future a reality.

Where do we need cost savings?

To get you going, here are some parts of common 3D Printers which think need to find cost-saving solutions.

XYZ AND HOT END MOTORS

Stepper motors are going to run you about $15 each. Is it possible to use cheaper DC motors with some type of position tracking while keeping the cost down?

HARDWARE

Threaded rod is probably the cheapest way to move your XYZ axis. What about couplings and guide rods? Check out how this guy made a CNC out of parts from his local hardware store.

ELECTRONICS

No arduino with Easysteppers here – too expensive. We’ve just seen a super cheap controller a few days ago. If we use something other than NEMA steppers, it will radically change the typical electronic controller for our super cheap 3d printer.

EXTRUDER

What is the cheapest way to melt and extrude plastic? What about using thermistors in place of thermocouples? Let’s think out of the box with this, and see if we can get away from the typical stepper motor based extruder. Remember, everything is low cost. If we have to sacrifice some resolution, that is OK.

So there you go. Let’s hear your input on the issue. We need to make 3D printers a lot more affordable and we want to hear any ideas you have on the topic in the comments below. Do you think this is in our future and why?

The 2015 Hackaday Prize is sponsored by:

Bringing A Century Stereo Into The 21st Century

June 9, 2015 by 14 Comments

Way back in the previous century, people used to use magnetized strips of tape to play music. It might be hard to believe in today’s digital world, but these “cassette” tapes were once all the rage. [Steve] aka [pinter75] recently found a Bang & Olufsen stereo with this exact type of antequated audio playback device, and decided to upgrade it with something a little more modern.

Once the unit arrived from eBay and got an electronic tune-up, [pinter75] grabbed a Galaxy S3 out of his parts drawer and got to work installing it in the old cassette deck location. He used a laser cutter to make a faceplate for the phone so it could be easily installed (and removed if he decides to put the tape deck back in the future).

The next step was wiring up power and soldering the audio output directly to the AUX pins on the stereo. Once everything was buttoned up [pinter75] found that everything worked perfectly, and mounted the stereo prominently on his wall. It’s always great when equipment like this is upgraded and repaired rather than thrown out.

Hackaday Prize Entry: Useful Code For Useful Things

June 8, 2015 by 18 Comments

The Hackaday Prize isn’t exclusively about building things that will help the planet; you can also build things that will enable others to build things to save the planet. [Eric] isn’t saving the world with his commonCode library, but it will make it vastly easier for other people to build the next great Thing.

The idea behind commonCode is the same as shared libraries you’ll find in any desktop application of reasonable size; it provides a common library for AVR microcontrollers to build just about anything. Bit manipulation, an interface for timers, math functions, graphics, I/O, and peripheral drivers are all available in the commonCode library. This makes it easy for the developmentally challenged among us to create whatever project they want.

The commonCode library wasn’t created just for The Hackaday Prize. [Eric] has been tinkering around with AVRs since well before the Arduino existed, and he has dozens of projects in permanent installations. It’s a great way to give back to the community, and the perfect way to allow people to develop their own things to solve whatever problem they have in mind.

The 2015 Hackaday Prize is sponsored by:

Subwoofer Vortex Cannon: 300V Of “Thwup!”

June 8, 2015 by 20 Comments

Need a cool toy for your kids? How about something with a bunch of fun fluid dynamics and a tinge of higher-than-average-voltage danger? Did we mention the subwoofer and bank of high-voltage capacitors? Have we got the project for you: [Robert Hart]’s vortex cannon design.

We’ve seen vortex cannons before, where you usually fix a balloon to the back of a trash can. Pull on the balloon membrane and then let it go with a snap, and it sends out a swirling donut of high-pressure air that travels surprisingly far. It’s like smoke rings, but amped up a bit.

[Robert]’s addition is to bolt on a high-power subwoofer in place of the balloon’s rubber membrane, and generate the air pulse by dumping a capacitor bank into the speaker.

6699171432446530681The circuit design is a bit more clever than we thought at first. The bottom half is a voltage inverter followed by a diode bridge rectifier that essentially makes 320V DC (peak) out of 12V, and stores this in four fairly large capacitors. A pushbutton activates a relay that dumps the capacitors through the speaker.

On top of the circuit is a -12V voltage inverter. Just before firing, the speaker is pulled back a little bit by applying this -12V to the speaker, and then the relay is triggered and the capacitors dump, shooting the speaker cone forward.

6973681433156869012[Robert] is still developing and testing the device out, so if you’re curious or just want to say hi, head on over to Hackaday.io and do so! Be sure to check out his videos. The smoke tests are starting to look good, and we love the control box and high-voltage warning stickers.

Hacking The IM-ME To Open Garages

June 8, 2015 by 32 Comments

If you have a wireless controlled garage door, a child’s toy can wirelessly open it in a few seconds. [Samy Kamkar] is a security researcher who likes to”think bad, do good”. He’s built OpenSesame, a device that can wirelessly open virtually any fixed-code garage door in seconds, exploiting a new attack he’s discovered in wireless fixed-pin devices, using the Mattel IM-ME toy.

The exploit works only on a gate or garage which uses “fixed codes”. To prevent this type of attack, all you need to do is to upgrade to a system which uses rolling codes, hopping codes, Security+ or Intellicode. These are not foolproof from attack, but do prevent the OpenSesame attack along with other traditional brute forcing attacks. It seems there are at least a couple of vendors who still have such vulnerable products, as well as several more whose older versions are affected too.

Before you read further, a caveat – the code released by [Samy] is intentionally bricked to prevent it from being abused. It might work, but just not quite. If you are an expert in RF and microcontrollers, you could fix it, but then you wouldn’t need his help in the first place, would you?

The IM-ME is a defunct toy and Mattel no longer produces it, but it can be snagged from Amazon or eBay if you’re lucky. The Radica Girltech IM-ME texting toy has been extensively hacked and documented. Not surprising, since it sports a TI CC1110 sub-GHz RF chip, an LCD display, keyboard, backlight, and more.  A good start point is the GoodFET open-source JTAG adapter, followed by the work of [Travis Godspeed] , [Dave] and [Michael Ossmann].

One issue with fixed code systems is their limited key space. For example, a remote with 12 binary dip switches supports 12 bits of possible combinations. Since its binary and 12 bits long, that’s 2^12, which is 4096 possible combinations. With a bit of math, [Samy] shows that it takes 29 minutes to open an (8-12)-bit garage, assuming you know the frequency and baud rate, both of which are pretty common. If you have to attempt a few different frequencies and baud rates, then the time it takes is a multiple of 29 minutes. If you don’t transmit the codes multiple times, and remove the pauses in between codes, the whole exercise can be completed in 3 minutes.

The weak link in the hardware is how the shift registers which decode the received codes work. Each bit is loaded in the register sequentially, gradually moving as additional bits come in and push the previous ones. This, and using an algorithm [Samy] wrote based on the De Bruijn sequence, the whole brute force attack can be completed in just over 8 seconds. OpenSesame implements this algorithm to produce every possible overlapping sequence of 8-12 bits in the least amount of time.

You can take a look at understanding how the code works by checking it out on Github. [Samy] loves doing such investigative work – check out his combo lock code breaker we featured recently, the scary, keyboard sniffing wall wart and the SkyJack – a drone to hack all drones.

Continue reading “Hacking The IM-ME To Open Garages” →

Hard Drive Rootkit Is Frighteningly Persistent

June 8, 2015 by 82 Comments

There are a lot of malware programs in the wild today, but luckily we have methods of detecting and removing them. Antivirus is an old standby, and if that fails you can always just reformat the hard drive and wipe it clean. That is unless the malware installs itself in your hard drive firmware. [MalwareTech] has written his own frightening proof of concept malware that does exactly this.

The core firmware rootkit needs to be very small in order to fit in the limited memory space on the hard drive’s memory chips. It’s only a few KB in size, but that doesn’t stop it from packing a punch. The rootkit can intercept any IO to and from the disk or the disk’s firmware. It uses this to its advantage by modifying data being sent back to the host computer. When the computer requests data from a sector on the disk, that data is first loaded into the disk’s cache. The firmware can modify the data sitting in the cache before notifying the host computer that the data is ready. This allows the firmware to trick the host system into executing arbitrary code.

[MalwareTech] uses this ability to load his own custom Windows XP bootkit called TinyXPB. All of this software is small enough to fit on the hard drive’s firmware. This means that traditional antivirus cannot detect its presence. If the owner of the system does get suspicious and completely reformats the hard drive, the malware will remain unharmed. The owner cannot even re-flash the firmware using traditional methods since the rootkit can detect this and save itself. The only way to properly re-flash the firmware would be to use an SPI programmer, which would be too technical for most users.

There are many more features and details to this project. If you are interested in malware, the PDF presentation is certainly worth a read. It goes much more in-depth into how the malware actually works and includes more details about how [MalwareTech] was able to actually reverse engineer the original firmware. If you’re worried about this malicious firmware getting out into the wild, [MalwareTech] assures us that he does not intend to release the actual code to the public.