Running Linux On A Thermostat

June 10, 2019 by 8 Comments

When your thermostat comes with Linux running on it, that’s not a hack. When it doesn’t, and you get Linux on there yourself, it most definitely is. This is exactly what [cz7asm] has done. In a recent video, he shows the Honeywell thermostat booting Linux and running a wide range of software.

While the hardware inside the thermostat doesn’t afford all the luxuries of a typical modern embedded Linux, it’s got enough room for the basics. The system runs from a 1 MB rootfs in RAM, and has a 2.5 MB kernel image, leaving a spare 12 MB for everything else. With just these meager resources, [cz7asm] shows how the system can use a USB network adapter, connecting to telehack.com for some command-line retro fun, and host a web server, although no browser runs yet. There’s also framebuffer support for displaying graphics and animations, and the usual Linux terminal goodness.

All we’ve seen so far is the video, so we hope [cz7asm] posts the code somewhere, because we’re tired of using our thermostat just to run the AC.

You might remember [cz7asm] from his previous thermostatic triumph: running Doom. Check out the video of the latest thermostat adventure after the break.

Thanks to [Piecutter] for the tip!

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C++ Reverbs From A Matlab Design

June 8, 2019 by 6 Comments

The guitar ‘Toing’ sound from the ’70s was epic, and for the first time listener it was enough to get a bunch of people hooked to the likes of Aerosmith. Reverb units were all the rage back then, and for his DSP class project, [nebk] creates a reverb filter using Matlab and ports it to C++.

Digital reverb was introduced around the 1960s by Manfred Schroeder and Ben Logan. The system consists of essentially all pass filters that simply add a delay element to the input signal and by clubbing a bunch together and then feeding them to a mixer. The output is then that echoing ‘toing’ that made the ’80s love the guitar so much. [Nebk]’s take on it enlists the help of the Raspberry Pi and C++ to implement the very same thing.

In his writeup, [nebk] goes through the explaining the essentials of a filter implementation in the digital domain and how the cascaded delay units accumulate the delay to become a better sounding system. He also goes on to add an FIR low pass filter to cut off the ringing which was consequent of adding a feedback loop. [nebk] uses Matlab’s filter generation tool for the LP filter which he includes the code for. After testing the design in Simulink, he moves to writing the whole thing in C++ complete with the filter classes that allows reading of audio files and then spitting out ‘reverbed’ audio files out.

The best thing about this project is the fact that [nebk] creates filter class templates for others to play with. It allows those who are playing/working with Matlab to transition to the C++ side with a learning curve that is not as steep as the Himalayas. The project has a lot to learn from and is great for beginners to get their feet wet. The code is available on [GitHub] for those who want to give it a shot and if you are just interested in audio effects on the cheap, be sure to check out the Ikea Reverb Plate that is big and looks awesome.

The Finest Linux Tablet You Can Build

June 6, 2019 by 45 Comments

For the last few years now, we’ve all had access to tiny, affordable Systems on a Module. These wunderchips are complete Linux systems with WiFi, a halfway decent GPU, and enough memory to run a real system. This is the perfect platform to base a tablet build on, the only problem is that someone has to actually do it. The DLT One is the ‘Damn Linux Tablet’ from [Prof. Fartsparkle]. It’s the answer to the question of when someone is going to build a tablet computer around one of these cheap Systems on a Chip that are floating around.

With many modules to choose from, the first task is actually choosing one of these Linux modules. [Fartsparkle] ended up with the Nvidia Jetson Nano, an impressive little board that has one distinct advantage: it’s drop-in compatable with the Raspberry Pi Compute Module, the Raspberry Pi-on-an-SODIMM. Given a single chassis, [Prof. Fartsparkle] can simply upgrade his tablet by getting a newer version of the Jetson Nano (or the Compute Module).

The current state of the board is basically an SODIMM socket on a board, with breakouts for Ethernet, a power jack, USB, and HDMI. That’s all there is to it, and design on the tablet chassis is ongoing.

Future updates for this tablet build will include USB-C PD, an mPCI-E connector that would allow for M.2 storage, LTE in some form or another and a dock that would allow you to turn this into a Surface-like laptop. It’s an amazing build, and one of the best entries we’ve seen in this year’s Hackaday Prize.

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Mobile SIGINT Hacking On A Civilian’s Budget

June 5, 2019 by 19 Comments

Signals Intelligence (SIGINT) refers to performing electronic reconnaissance by eavesdropping on communications, and used to be the kind of thing that was only within the purview of the military or various three letter government agencies. But today, for better or for worse, the individual hacker is able to pull an incredible amount of information out of thin air with low-cost hardware and open source software. Now, thanks to [Josh Conway], all that capability can be harnessed with a slick all-in-one device: the RadioInstigator.

In his talk at the recent 2019 CircleCityCon, [Josh] (who also goes by the handle [CrankyLinuxUser]) presented the RadioInstigator as an affordable way to get into the world of wireless security research beyond the traditional WiFi and Bluetooth. None of the hardware inside the device is new exactly, it’s all stuff the hacking community has had access to for a while now, but this project brings them all together under one 3D printed “roof” as it were. The end result is a surprisingly practical looking device that can be used on the go to explore huge swaths of the RF spectrum at a cost of only around $150 USD.

So what has [Josh] packed into this wireless toybox? It will probably come as little surprise to find out that the star of the show is a Raspberry Pi 3 B+, combined with a touch screen display and portable keyboard so the user can interface with the various security tools installed.

To help the RadioInstigator surf the airwaves there’s an RTL-SDR and a 2.4 Ghz nRF24LU1+ “Crazyradio”, both broken out to external antenna connectors on the outside of the device. There’s even an external SMA connector hooked up to the Pi’s GPIO pin, which can be used for low-power transmissions from 5 KHz up to 1500 MHz with rpitx. Everything is powered by a beefy 10,000 mAh battery pack which should give you plenty of loiter time to perform your investigations.

[Josh] has also written several Bash scripts which will get a trove of radio hacking tools installed on the Pi automatically, either by pulling them in through the official repositories or downloading the source and compiling them. Getting the software environment into a known-good state can be a huge time sink, so even if you don’t build your own version of the RadioInstigator, his scripts are still worth checking out.

You can do some pretty incredible things with nothing more than a Pi and an RTL-SDR, but we can’t help but notice there’s still plenty of room inside the RadioInstigator for more gear. It could be the perfect home for a Mult-RTL setup, or maybe even a VGA adapter for spoofing cell networks.

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Tiny Wooden Laptop Packs Raspberry Pi

May 28, 2019 by 8 Comments

Building a handheld Raspberry Pi rig is practically a hacker rite of passage these days. Off-the-shelf parts keep getting better, and we’re now starting to see affordable compact LCD screens with decent resolution become common. [MakeFailRepeat] got his hands on a HyperPixel screen, and decided to whip up a neat project with it.

The result is a charming little laptop, packing a 4″ screen with 800×480 resolution. Input is via multi-touch, as well as an integrated keyboard. The frame of the laptop is wooden, with a 3D printer supplying parts for the hinge mechanism. To round out the aesthetics, the top of the device was given a decorative copper inlay. Power management is via a UPS hat, which allows the device to switch seamlessly between battery and mains power.

A project like this is a great way to learn a wide range of valuable skills. It involves woodworking and 3D design, as well as the basic configuration of a single board computer. They come in all shapes and sizes, like this tiny RetroPie handheld, or this slick laptop build. Video after the break.

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Depotting An Ancient Car Computer

May 27, 2019 by 25 Comments

Carburettors were king for decades, until the onward march of technology brought electronic fuel injection to the fore. During their final years, a handful of automakers experimented with computer control of the humble carb, trying to squeeze out every last bit of efficiency and reduce pollution as much as possible. [NeXT] happened to own a vehicle fitted with AMC’s Computerized Engine Control system, and decided to see what made it tick.

This was easier said than done due to choices made by Ford, who manufactured the engine computer for AMC. Unlike modern ECUs which usually feature a metal case fitted with rubber gaskets, the CEC computer was potted in epoxy. [NeXT] was able to de-pot the circuit board by placing it in a stock pot of boiling water, and then slowly peeling the epoxy away.

With the potting removed, it was possible to begin reverse engineering the board. The main microcontroller is an Intel 8049, of the MCS-48 family. The board uses through-hole technology, and only features a handful of other small ICs.

It’s always interesting to look back at forgotten technologies and see how things were done in decades past. [NeXT] hopes to keep working on the project, intending to dump the ROM from the CEC module and build a replacement computer with an Arduino. It’s possible to build your own ECU from scratch, so we’re looking forward to seeing [NeXT]’s AMC Eagle running on modern silicon real soon.

Retrocomputing For The Masses Hack Chat

May 27, 2019 by 6 Comments

Join us on Wednesday 29 May 2019 at noon Pacific for the Retrocomputing for the Masses Hack Chat!

Of the early crop of personal computers that made their way to market before IBM and Apple came to dominate it, few machines achieved the iconic status that the Sinclair ZX80 did.

Perhaps it was its unusual and appealing design style, or maybe it had more to do with its affordability. Regardless, [Sir Clive]’s little machine sold north of 100,000 units and earned a place in both computing history and the hearts of early adopters.

Spencer Owen is one who still holds a torch for the ZX80, so much so that in 2013, he hatched a seemingly wacky idea to make his own. A breadboard prototype of the Z80 machine slowly came to life over Christmas 2013, one thing led to another, and the “RC2014” was born.

The RC2014 proved popular enough to sell on Tindie, and Spencer is now following his dream as a retrocomputing mogul and working on RC2014 full time. He’ll be joining us to discuss the RC2014, how it came to be, and how selling computing nostalgia can be more than just a dream.

join-hack-chatOur Hack Chats are live community events in the Hackaday.io Hack Chat group messaging. This week we’ll be sitting down on Wednesday May 29 at 12:00 PM Pacific time. If time zones have got you down, we have a handy time zone converter.

Click that speech bubble to the right, and you’ll be taken directly to the Hack Chat group on Hackaday.io. You don’t have to wait until Wednesday; join whenever you want and you can see what the community is talking about.