Core Memory for the Hard Core

[Brek] needed to store 64 bits of data from his GPS to serve as a last-known-position function. This memory must be non-volatile, sticking around when the GPS and power are off. Solutions like using a backup battery or employing a $0.25 EEPROM chip were obviously too pedestrian. [Brek] wanted to store his 64 bits in style and that means hand-wired core memory.

OK, we’re pretty sure that the solution came first, and then [Brek] found a fitting problem that could be solved, but you gotta give him props for a project well executed and well documented.

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Driving a 7 Segment LED Display From An FT232

Sometimes, a good hack is about using less rather than more. That’s the case with this neat tutorial from [Rahul.S] on driving a 7-segment LED display with an FT232. By using this cheap USB to serial controller, [Rahul.S] was able to drive the display directly without using a microcontroller, which keeps the component cost down.

He’s bit banging an octal buffer connected to the display. You may be surprised to find that the FT232 chips do have enough outputs to make this work. Rather than send serial data number to the display and have a controller convert this into a set of signals that make the number, this conversion is done by the PC, which then sends a signal that directly illuminates the appropriate parts of the LED. By using all of the available output lines of the FT232 (including ones like the RTS/CTS line that are usually used for signalling), [Rahul.S] was able to drive all seven of the elements and the decimal point.

Of course, cynics may argue that it would be simpler to use a cheap serial LCD display. That is true, but there is always something to be said for knowing how to do something yourself rather than letting others do it for you… Continue reading “Driving a 7 Segment LED Display From An FT232”

Spectrum Painting on 2.4 GHz

Give a software-defined radio (SDR) platform to a few thousand geeks, and it’s pretty predictable what will happen: hackers gotta hack. We’re only surprised that it’s happening so soon. Spectrum Painter is one of the first cool hacks to come out of the rad1o badge given out at the CCCamp 2015. It makes it dead-simple to send images in Hellschreiber mode on a few different SDR hardware platforms.

What we especially like about the project is its simplicity. Don’t get us wrong, we’re tremendous fans of GNURadio and the GNURadio Companion software radio hacking environment. But if you just want to do something simple, like send a picture of a smiley-face, the all-capable GNURadio suite is overkill.

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Developed on Hackaday: Let’s build an Electronic Hackaday Badge

We’re going to build an electronic Hackaday Badge, and by “we”, I mean Hackaday community members who are passionate about the project.

I’ll be leading the charge. I had a great learning experience the last time I helped design the e-paper badge for the 2013 Open Hardware Summit, and hope to learn a lot along the way this time too. Since then, Badges have come a long way – at cons like DEFCON, LayerONE, Shmoocon, The Next Hope, Open Hardware Summit, The EMF, SAINTCON, SXSW Create, The Last Hope, TROOPERS11, ZaCon V and of course the rad1o from this year’s CCCamp. Word is that this year’s Open Hardware Summit badge is going to be pretty kickass too. So, we have some very big shoes to fill. But this doesn’t have to be about “my badge is better than yours”. And this badge isn’t meant to be specific to any single con or event. So what does the Badge do, then? “It’s a physical extension of the community, made specifically for hacker gatherings of all types and sizes.”

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HDMI is implemented on just about every piece of sufficiently advanced consumer electronics. You can find it in low-end cellphones, and a single board Linux computer without HDMI is considered crippled. There’s some interesting stuff lurking around in the HDMI spec, and at DEF CON, [Joshua Smith] laid the Consumer Electronics Control (CEC) part of HDMI out on the line, and exposed a few vulnerabilities in this protocol that’s in everything with an HDMI port.

CEC is designed to control multiple devices over an HDMI connection; it allows your TV to be controlled from your set top box, your DVD player from your TV, and passing text from one device to another for an On Screen Display. It’s a 1-wire bidirectional bus with 500bits/second of bandwidth. There are a few open source implementations like libCEC, Android HDMI-CEC, and even an Arduino implementation. The circuit to interface a microcontroller with the single CEC pin is very simple – just a handful of jellybean parts.

[Joshua]’s work is based off a talk by [Andy Davis] from Blackhat 2012 (PDF), but greatly expands on this work. After looking at a ton of devices, [Joshua] was able to find some very cool vulnerabilities in a specific Panasonic TV and a Samsung Blu-ray player.

A certain CEC command directed towards the Panasonic TV sent a command to upload new firmware from an SD card. This is somewhat odd, as you would think firmware would be automagically downloaded from an SD card, just like thousands of other consumer electronics devices. For the Samsung Blu-Ray player, a few memcpy() calls were found to be accessed by CEC commands, but they’re not easily exploitable yet.

As far as vulnerabilities go, [Joshua] has a few ideas. Game consoles and BluRay players are ubiquitous, and the holy grail – setting up a network connection over HDMI Ethernet Channel (HEC) – are the keys to the castle in a device no one  would ever think of taking a close look at.

Future work includes a refactor of the current code, and digging into more devices. There are millions of CEC-capable devices out on the market right now, and the CEC commands themselves are not standardized. The only way for HDMI CEC to be a reliable tool is to figure out commands for these devices. It’s a lot of work, but makes for a great call to action to get more people investigating this very interesting and versatile protocol.

BeagleBone Green Hands-On: Lower Price, Same Horsepower

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.

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Secrets Of The Lexus Hoverboard Revealed

Auto site [Jalopnik] got some hands-on (or rather feet-on) time with the Lexus hoverboard that was built for an advert for the luxury car brand, and their video reveals a few secrets about how this interesting device works. It is definitely real: the Jalopnik writer got to ride it himself, and described it as “Unbelievably difficult yet at the same time unbelievably cool, both because you’re levitating and because the board is filled with magnets more than 300 degrees below zero“. But a look behind the scenes reveals that it is another tease.

The device looks like it is a real hoverboard, floating several inches above the surface and even traveling over water, a feat that Marty McFly couldn’t do. But, as usual, there is a little more going on than meets the eye. The device is built around superconducting magnets cooled by liquid nitrogen, so it only works for about 10 minutes. After that, you have to refill the device with liquid nitrogen. The surface that the board is floating over also has what the Jalopnik writer describes as having “several hundred thousand dollars worth of magnets built in“. Try this on a non-magnetic surface and you’ll come to a grinding halt. If you watch the video of the hoverboard serenely gliding over the water from another angle, you can see a magnetic track just under the surface. If you run off this track, you’ll end up with wet feet.

Is it a neat hack? Yes. Is it cool? Yes. Is it the future of transportation? No: it is a cool hack put together for a car advert with a big budget. Kudos to Lexus for spending the cash to do it properly, but once again, our dreams of hoverboards are dashed in the cold, hard light of reality. Darn.