Having a serial port on any Linux box is always useful, but with the tiny computers we’re carrying around in our pockets now, that isn’t always an option. Some of the more advanced phones out there break out a UART on their USB OTG port, but the designers of the Nexus 4 decided to do things differently. They chose to put the Nexus 4′s serial port on the mic and headphone input, and [Ryan] and [Josh] figured out how to access this port.

Basically, the Nexus 4 has a tiny bit of circuitry attached to the microphone input. If the Nexus detects more than 2.8 Volts on the mic, it switches over to a hardware UART, allowing everything from an Arduino to an old dumb terminal to access the port.

The guys used a USB to serial FTDI board wired up to a 3.5 mm jack with a few resistors to enable the hardware UART on their phone. With a small enclosure, they had a reasonably inexpensive way to enable a hardware serial port on a mobile device with GPS, cellular, a camera, and a whole bunch of other sensors that any portable project would love.

EDIT: An anonymous little bird told us this: “You should add a note to the Nexus 4 serial cable post that TX and RX need to be 1.8V.  If you use 3.3V USB cables, you will likely eventually fry something.  FTDI makes 1.8V IO cables that work – you just need to make the trigger voltage for the mic line.” Take that for what you will.

In 1979, [Nolan Bushnell] released Asteroids to the world. Now, he’s playing the game again, only this time with the help of a laser projector and a Kinect that turns anyone sitting on a stool – in this case [Nolan] himself – into everyone’s favorite vector spaceship. It’s a project for Steam Carnival, a project by [Brent Bushnell] and [Eric Gradman] that hopes to bring a modern electronic carnival to your town.

The reimagined Asteroids game was created with a laser projector to display the asteroids and ship on a floor. A Kinect tracks the user sitting and rolling on a stool while a smart phone is the triangular spaceship’s ‘fire’ button. The game is played in a 150 square foot arena, and is able to put anyone behind the cockpit of an asteroid mining triangle.

[Brent] and [Eric] hope to bring their steam carnival to LA and San Francisco next spring, but if they exceed their funding goals, they might be convinced to bring their show east of the Mississippi. We’d love to try it out by hiding behind the score like the original Asteroids and wasting several hours.

We’re pretty spoiled these days in that hobby electronics has made a lot of cool tools available on a budget. It’s hard to think of a better example than a logic analyzer, which you can get for a day or two of pay. Consumer-level devices just didn’t exist until a few years ago. [Jouko S] has this HP16500B industrial grade logic analyzer in his shop. It’s from the early 1990′s and it’s got a ton of features. Grabbing a still functional yet super-old model used to be the only way for hobbyists. But one thing you won’t find on it is the ability to connect it to your USB port to get screen captures. Younger readers might not recognize the slot at the top for magnetic media called a floppy disk which is the in-built way of recording your sessions. He set out to find an easier way to get color screen captures and ended up adding RS-232 control to the old hardware.

There is a 25-pin port on the back of the old hulk. But it is a female connector and he didn’t have the adapters on hand to make it work with his serial-to-USB converter. During development he used a breadboard and solder-tail connector to patch into the necessary signals. This was all hooked up to a Raspberry Pi which he planned to dedicate to the system. It worked, and he was able to use an interactive terminal for the rest of his sleuthing. With much trial and error he figured out the commands, and wrote some Python code for the Pi side of the equation. He can now pull color screenshots with ease thanks to the utilities available in the Python Imaging Module.

The age of ARM microcontrollers for the electronics hobbyist is upon us, and luckily there are a few breadboard-friendly microcontrollers available in a DIP package. One of these chips is NXP’s LPC810M021FN8 – a tiny little 8-pin DIP with 4 kB of Flash, 1 kB of SRAM, and has a clock fast enough for some really cool stuff. [Joao] needed a way to program one of these microcontrollers and came up with an easy method using only a USB/UART adapter.

The key to this build is the fact the LPC810 doesn’t need any additional components to operate; the internal oscillator means the chip will run at 30 MHz with only a power and ground attached. To program the chip, [Joao] attached the Tx and Rx lines of the chip to a USB/UART adapter (at 3.3 V, of course), and uploaded some code with Flashmagic.

We’ve seen these DIP-sized ARM chips before, but [Joao]‘s method of using off-the-shelf tools to write a blinking LED program means it’s a piece of cake to start working with these very cool and very powerful microcontrollers.

Don’t heat up your house this summer, build your own backyard pizza oven instead. We love to using our garden produce, homemade dough, and fresh farmer’s market mozzarella to whip up a tasty pie in the summer. But it can be tricky to cook it on the grill and we hate heating up the oven when it’s hot out. This could be a perfect solution.

The footprint of the oven used to be a flower bed in [Furiousbal's] yard. He removed the soil and side walls, laid down a bed of pea gravel, then started building the brick base for the oven. The base is insulated by encasing beer bottles in a bed of clay which he harvested locally. Fire brick then makes the floor of the cooking area as well as the arched opening. To support the clay during construction he built a dome of wet sand and covered it with damp newspaper. The clay is built up in layers before removing the sand from the inside. The final step (not shown above) is to build a little shelter to ensure the elements don’t wash away your hard work.

Of course you need to build your own fire inside to use it. If that’s too much work perhaps you should try solar cooking?

[via Reddit]

Help us decide, should this project gone on LIFE.hackaday?

This is exactly what it looks like. [Oleg] calls it soldering in inert atmosphere, but it’s just a toaster oven reflow hack dropped into a container full of carbon dioxide.

Why go to this trouble? It’s all about solder wetting. This is the ability of the molten solder paste to flow into all of the tinned areas of a board. [Oleg] talks about the shelf life of hot air leveled PCB tinning, which is about six months. After this the tin has oxidized. It will certainly not be as bad as bare copper would have, but it can lead to bad solder joints if your PCBs are more than about six months off the production line. This is one of the reasons to use solder flux. The acid eats away at the oxidized layer, exposing tin that will have better wetting.

But there is another way. Soldering in the absence of oxygen will also help the wetting process. CO2 is heavier than air, so placing the reflow oven in a plastic container will allow you to purge air from the space. CO2 canisters are cheap and easy to acquire. If you keg your own homebrew beer you already own one!

If you’ve got everything but the reflow oven just look around for a few examples of how to build your own.

Charlotte’s chassis comes from as a kit, but the stock electronics are based on an Arduino – not something for a robot that needs to run computer vision apps. [Kevin] ended up using a Raspi for the controller and gave Charlotte eyes with an Asus XTION. Edit: or a PrimeSense sensor These sensors are structured light depth cameras just like the kinect, only about smaller, lighter, and have a better color output.

Hardware is only one half of the equation, so [Kevin] tossed the Arduino-based stock electronics and replaced them with a Raspberry Pi. This allowed him to hone his C++ skills and add one very cool peripheral – the XTION depth camera.

To the surprise of many, we’re sure, [Kevin] is running OpenNI on his Raspberry Pi, allowing Charlotte to take readings from her depth camera and keep from colliding into any objects. The Raspberry Pi is overclocked, of course, and the CPU usage is hovering around 90%, but if you’re looking for a project that uses a depth sensor with a Pi, there you go.

The advent of the Arduino brought the world of microcontrollers to hobbyists, students, and artist the world over. Right now we’re in the midst of a new expansion in hobbyist electronics with the Raspberry Pi, but we can’t expect everyone to stay in the comfortable, complex, and power-hungry world of Linux forever, can we? Eventually all those tinkerers will want to program a microcontroller, and if they already have a Raspberry Pi, why not use that?

[Kevin] wanted to turn his Raspi into an AVR development workstation, without using any external programmers. He decided to use the Raspi’s SPI port to talk to an AVR microcontroller and was able to make the electrical connections with just a few bits of wire an a handful of resistors.

For the software, [Kevin] added support for SPI to avrdude, available on his git. Theoretically, this should work with any AVR microcontroller with the most popular ATMegas and ATtinys we’ve come to love. It doesn’t support the very weird chips that use TPI programming, but it’s still extremely useful.

We don’t have an Ambilight clone on our own home theater, but seeing this one in action makes us wonder if we shouldn’t add it to the ever-growing list of projects we need to tackle (right below that POV display we’ve been putting off for years). [Falldeaf] built the colored light augmentation system using a set of WS2801 controlled LED pixels. There are a lot of them, and this results in the ‘meaningful resolution’ we mentioned in the title. The image on the screen is the opening to a James Bond film. You’ll remember that the camera shot down a rifle barrel follows him as he walks across the screen. There’s enough LEDs here to have to the light follow him across the screen as well. This is a nice touch that we don’t see in every Ambilight clone project.

A frame of fake-wood angle bracket holds each LED pixel in place. The entire assembly attaches to the VESA mounting holes on the back of the television. An Arduino addresses the lights while the Boblight package processes the video to acquire the lighting instructions. We think the hue is a bit off, but otherwise it’s a solid offering.

We’re still hoping the Microsoft IllumiRoom becomes a thing.

Over the years we’ve had a tons of tips sent in that were more along the lines of “lifehacks”. Simple little tips to make life better. While we would occasionally squeeze them into hackaday, many got left behind. Now we’ve created an entire site called LIFE.hackaday that we’re filling with all these great ideas. Finally, a place for all those docks people send us!

Occasionally, there might be something that we feel works for the “classic” hackaday and “LIFE.”, in which case, we may just mention it here. We hope that by creating another site, we can give people the “lifehacks” they want while keeping hackaday focused on hardware hacking.

We have some other tricks up our sleeve, but they aren’t quite ready to be revealed yet.

As a software developer, [suka] spends a lot of time every day in front of a keyboard. He had been trying out different keyboard layouts far less common than even the moderetly obscure Dvorak layout, and after some time decided a custom ergonomic keyboard was what he wanted. His progress of designing his own custom ergonomic keyboard is a fascinating read, made even cooler by the fact these are real, professional-quality keyboards with mechanical switches and custom enclosures.

After starting off with a few USB numpads, [suka] dove in to the world of Cherry switches by crafting his own wing-style keyboard. [suka] works for one of the larger manufacturers of laser-sintering machines, so he was able to create the enclosures for his keybaord – as well as the key caps – fairly easily. The technology behind laser sintering allowed [suka] to create some strange bowl and trough-shaped keyboards before settling on his daily driver, seen above.

The Blue Cube, as [suka] calls it, includes an integrated stand, an integrated IBM trackpoint mouse, and is powered by a Teensy microcontroller. [suka]‘s keyboards might not be heafty enough for melee combat like the venerable IBM Model M, but it’s exactly what [suka] wants, and that’s just fine by us.

[Radu] spend the first portion of this year building and improving upon this wireless rover project. It’s actually the second generation of an autonomous follower project he started a few years back. If you browse through his old postings you’ll find that this version is leaps and bounds ahead of the last.

He purchased the chassis which also came with the gear-head motors and tires. Why reinvent the wheel (har har) when you’ve got bigger things on your plate? To make enough room inside for his own goodies he started out by ditching the control board which came with the Lynxmotion chassis in favor of an AVR ATmega128 development board. He also chose to use his own motor controller board. Next he added a metal bracket system to hold the battery pack. Things start to get pretty crowded in there when he installed his own Bluetooth and GPS modules. Rounding out his hardware additions were a set of five ultrasonic sensors (the grey tubes on top), a character display, as well as head and tail lights. The demo video shows off the control app he uses. We like that tic-tac-toe design for motion control, and that he added in buttons to control the lights.

Simple tools used well can produce fantastic results. The hardware which [Gilad] uses in this project is the definition of common. We’d bet you have most if not all of them on hand right now. But the end product is a light box which seems to dance and twirl with every sound in the room. You should go watch the demo video before reading the bill of materials so that the simplicity doesn’t spoil it for you.

A wooden craft box serves as the enclosure. Inside you’ll find an Arduino board, microphone, and an 8×8 RGB module. The front cover of the project box diffuses the light using a sheet of tracing paper on a frame of foam board. It’s the code that brings everything together. He wrote his own particle system library to generate interesting animations.

If you don’t have a project box on hand this might work with an extra-deep picture frame.

If you want to get an old Apple, Commodore 64, Amiga, or any other retrocomputer up on the Internet, this is for you. [Stian] had an Amiga 500 lying around and wanted to put it on a network. The A500 isn’t expandable, so he needed to look at some sort of adapter to put it on a network. The solution came to him in the form of a Raspberry Pi, a null modem cable, and a few bits of software.

To connect his Amiga to his network, [Stian] made a small serial converter board for his Raspi that breaks out the Tx and Rx pins on the Pi to a 9-pin serial port. With the physical connection to the Pi made, the only thing left to do was to get some software for the Amiga, namely AmiTCP and PPP. It’s not exactly a fast network connection, but this build allows [Stian] to connect to WiFi networks with ancient hardware.

One interesting aspect of [Stian]‘s build is the fact it’s completely transferable to other retrocomputers – everything from old S-100 bus computers to classic macs, apples, and pretty much anything else with a serial port that supports PPP. Even with the expense of a Raspberry Pi, it’s much cheaper than absurdly expensive second-hand SCSI to Ethernet controllers and other tomfoolery.

Transcranial Direct Current Stimulation – or tDCS – is the technique of applying electrodes to the skull and running a small but perceptible current through them. It’s not much current – usually on the order of 1 or 2 mA, but the effect of either increasing or decreasing neural activity has led to some interesting studies. [Theo] over on Instructables wrote a tutorial for making his own tDCS suppy that will supply 2 mA to electrodes placed on the skull for everyone to experiment with.

The basic idea behind tDCS is to put the positive electrode over the part of the brain to be excited or the negative electrode over the part of the brain to be inhibited. This is a well-studied technique that can be used to improve mathematical ability. It’s not electroshock therapy (although that is a valid treatment for depression and schizophrenia) in that a seizure is induced; tDCS just applies a small current to specific areas of the brain to excite or inhibit function.

[Theo]‘s device is a simple circuit made of a transistor, resistors, and a few diodes to provide about 2 mA to a pair of electrical contacts. With this circuit and a few gel electrode pads for your head, you too can experiment with direct current stimulation of your brain.

Of course we need to warn you about putting electricity into your head. In any event, here’s a quadcopter / stun gun mashup we made. Don’t do that, either. You might get a takedown request.

Ever wanted to make the jump from microcontrollers to logic chips? Although not technically the same thing we consider FPGA and CPLD devices to be in similar categories. Like FPGAs, Complex Programmable Logic Devices let you build hardware inside of a chip. And if you’ve got the knack for etching circuit boards you can now build your own CPLD development module. Long-time Hackaday readers will remember our own offering in this area.

Our years of microcontroller experience have taught us a mantra: if it doesn’t work it’s a hardware problem. We have a knack for wasting hours trying to figure out why our code doesn’t work. The majority of the time it’s a hardware issue. And this is why you might not want to design your own dev tools when just starting out. But one thing this guide has going for it is incremental testing. After etching and inspecting the board, it is populated in stages. There is test code available for each stage that will help verify that the hardware is working as expected.

The CPLD is programmed using that 10-pin header. If you don’t have a programmer you can build your own that uses a parallel port. Included on the board is an ATtiny2313 which is a nice touch as it can simulate all kinds of different hardware to test with your VHDL code. There is also a row of LEDs, a set of DIP switches, and a few breakout headers to boot.

[Don] uses a Continuous Glucose Monitor to stay on top of his diabetes. It means carrying around an expensive and fragile device which acts as the readout. He’s an active guy and doesn’t want to destroy the thing while dirt biking or kick boxing so he’s been trying to use a TI Chronos smart watch as a display alternative.

As you can see he has already made some headway. This image shows the watch displaying data from the device. Unfortunately he’s depending on a PC to interface with the CGM display, then pushing it to the watch. He may try moving to a Raspberry Pi to help make this more mobile. This way the sensitive hardware could be tucked safely in a case inside a backpack while the watch shows his current glucose levels. We’d also love to see an embedded solution that would emulate the communications the PC is using to harvest the data. If you’ve got any suggestions in this area we’re sure that [Don] would appreciate the help.

Timing is everything and that’s why most communication protocols require a very accurate clock source. The WS2811 LED strip controllers are no different. But [Danny] figured out a way to drive them reliably with an 8MHz clock source.

The WS2811 has become one of the most popular controllers for RGB pixels and strips alike. We’ve seen several hacks used to address them, including the 16MHz AVR technique that inspired [Danny] to take on this project. He planned to use that library but the 25-day shipping time for a 16MHz crystal drove home to invent a way to use the internal oscillator instead.

The gist of the hack is that he wrote assembly code to handle pairs of binary bit values. With a code block for each of the four possible combinations in hand he had to find a way to craft the conditional jumps to preserve accurate timing. After hitting the wall trying to solve this puzzle by hand he wrote a C++ program to solve it for home. The proof is in this video which shows one chip driving multiple Larson scanners on a single strip.

After months of promises, the Raspberry Pi camera is finally heading out to hackers and makers across the world. Of course the first build with the Pi cam to grace the pages of Hackaday would be removing the IR filter, and it just so happens [Gary] and his crew at the Reading hackerspace are the first to do just that.

As [Gary] shows in his video, the process of removing the Pi cam’s IR filter is extremely fiddly.  Getting the filter out of the camera involves removing the sensor, gently cutting it open with a scalpel, and finally gluing the whole thing back together with a tiny bit of superglue. Not for the faint of heart, and certainly not for anyone without a halfway decent bench microscope.

If you’re looking for a Raspberry Pi-powered security camera, game camera, or something for an astronomy application, this is the way to make it happen. You might want to be careful when removing the IR filter; [Gary] broke one camera on their first attempt. They got it to work, though, and the picture quality looks pretty good, as seen in the videos below.

Stop whatever you’re doing and get this book. I’ve just finished reading it and I have to say that [Wendy] and [Mikey] could easily be the poster children for modern day hacking, and this book could be the manual for a life built on hacking.

When I visited [Wendy] and [Mikey] last year I was blown away.  Their little homestead was a veritable smorgasbord of hacks. Everywhere I looked, things were cobbled together, modified, repaired, and improved. There wasn’t a single piece of their lives that wasn’t somehow improved by their efforts to play an active role in their own living.

That sounds a bit cheesy I know. We all play an active role in our lives right? Sure. But what they have done is created a hacker’s homestead. My projects tend to live on my workbench, occasionally poking into my daily life, but they went were there was virtually nothing and hacked together everything they found they needed.  Their life is their workbench.

If there was a need, something would be made to satisfy that need. The buildings they built were constructed from scrap and paper, the power they use was harvested from their own cobbled together solar system and battery array, the food they eat was cultivated from the desert using intelligent planning. It was not only an impressive display of hacker ingenuity, but also inspiring.

The book basically comes in two parts.

Part 1. the Story:

[Wendy] and [Mikey] were hackers in New York. You might remember [Mikey] from some articles he wrote for hackaday ages ago, as well as his projects that appear on our pages. [Wendy] started swap-o-rama, which you may have also seen. This part of the book is an interesting view of hackers struggling to live two different ways at the same time (DIY/Hacking vs Get a job and be normal). Ultimately, they decided they would move to the middle of New Mexico and just make what they need.  They’ve been documenting this whole process on their blog, Holy Scrap, as well.

I wasn’t too interested in a “hackers falling in love” story, and I was pleasantly surprised to find that this is more of a first hand account of some of the cool stuff they were doing in New york. There are stories of things like when [Wendy] orchestrated a large event involving decorative burn barrels on the streets of New York, or that time when [Mikey] built a bunch of vibrating underwear with remote controls to pass out to strangers at burning man.

Part 2. the Lab.

After spending so much time doing what they do, they’ve compiled chapter upon chapter of projects to survive on. Ranging from electronics projects like harvesting and repairing car batteries to growing and harvesting your own medicinal plants, Creating entire buildings from old phone books to converting vehicles to run on grease. I think this section should be handed out in high schools as part of the curriculum.

In case you couldn’t tell, I loved this book. It almost seemed like a glimpse into an imaginary place that belonged in a [Niel Stephenson] book (I could imagine passing through this area in the Diamond Age). I should also mention that even though I did visit them last year, I don’t really know them. I knew they were in my path for that trip and shot them an email. They were fantastic hosts who fed us, amused us, and took us swimming in the Rio Grande.