The I2C Programmable NFC Tag

May 30, 2014 by Brian Benchoff 22 Comments

NFC NFC tags are cool, but programming them to do your bidding – whether unlocking your computer, making an Arduino vending machine, or a smart home application – requires using an NFC device to program the tag over the air. An NFC tag programmable with any ‘ol microcontroller would certainly have some interesting applications, and Elecfreaks’ DNFC tag is just the thing to test out these ideas.

While NFC tags are reprogrammable, reprogramming them requires an NFC controller, be that through a dedicated hardware, a phone, or an Arduino shield. The DNFC tag is reprogrammable with a microcontroller with an I2C interface thanks to TI’s RF430CL330H dynamic NFC transponder IC. It still does everything you would expect from a NFC tag – MIFARE compatible. NDEF reading and writing, and everything else – but you can program it through an Arduino, Pi, or any other board with an I2C interface.

TI has an app note on using the chip inside the DNFC for automatic Bluetooth pairing, and Elecfreaks themselves have a few use cases in mind that include putting WiFi credentials on an Arduino board without putting the SSID in code and other Internet of Things™ applications. We’re thinking this is one of those devices that is eminently useful, but for something we just can’t think of off the top of your head. If you’ve got an idea for how to use an I2C programmable NFC tag, drop a note in the comments.

Elecfreaks is doing an Indiegogo campaign for the DNFC, $13 for one. I picked one up, but it’s flexible funding, so buy it or don’t. I don’t care.

A Wireless Computer Remote That Emulates A USB Keyboard

May 25, 2014 by Nick Conn 7 Comments

PCRemote

If you are anything like [Antoine], you would love to be able to control your PC with a simple hand-held remote control from anywhere in your house. [Antoine] wrote in to tell us about his wireless computer remote that emulates a USB keyboard, making it suitable for any device that uses a USB keyboard.

His blog post is very well written and contains a ton of design information and background on the project. He initially wanting to easily control his PC’s music from anywhere in his house without needing to be within line of sight of his computer. The end result is a very handy remote that can be used to change music, video, and even launch applications on his computer. The system consists of a base station for his remote that connects to the computer and acts as a USB keyboard, and the remote itself. The base station uses V-USB on an Arduino to interface with the computer, and VirtualWire to handle the wireless protocol for the remote. For those of you who don’t know about VirtualWire (now superseded by RadioHead), it is a very cool Arduino library that lets you easily use raw wireless interfaces (also called vanilla wireless interfaces).

Without going into too much detail here (be sure to see the actual post for more information), the remote itself was redesigned after the initial proof of concept to maximize battery life. The final power consumption is very impressive, resulting in a battery life of more than two years! This remote system is very well put together and contains many aspects that can easily be reused for other projects.

Firmware For Cheap Bluetooth Modules

May 18, 2014 by Brian Benchoff 43 Comments

If you’ve ever built anything with a microcontroller, some sort of sensor, and a connection to the outside world, you’re probably wondering how those places in China can pump out cheap electronics for a mere percentage of what it costs you to pull a DIY. It’s not just volume – it’s engineering; if something has Bluetooth, you find a Bluetooth module with a built-in microcontroller so you can write firmware to it.

The BC417 is the System on Chip found in the very popular BlueCore4-Ext Bluetooth module featuring 8Mbits of Flash (75% of which is used for Bluetooth related stuff), somewhere around 12 kB of RAM, with everything run in a virtual machine. [pfalcon] wrote an extremely experimental firmware for this device that allows anyone to create a wireless sensor node for peanuts. These devices are almost as cheap as a bare ATMega, so the possibilities are interesting, to say the least.

At this point, the hardest part of putting custom firmware on these devices is programming them. For that, [Elastic Sheep] comes to the rescue with a parallel port to SPI interface. There’s also a firmware dumper and some breakout boards available. These modules are pretty cheap, and the pitch isn’t too bad, so you might be able to etch your own boards should you want to experiment a little.

Thanks [Peter] for sending this in.

MicroModem, For Data Transmission Explorations

May 15, 2014 by Brian Benchoff 24 Comments

modem Them kids with those Arduinos don’t know what they’re missing. A serial connection is just too easy, and there’s so much fun to be had with low bandwidth modems. [Mark] made the MicroModem with this in mind. It’s a 1200 baud AFSK modem, capable of APRS, TCP/IP over SLIP, mesh network experimentations, and even long-range radio communication.

As the MicroModem is designed to be an introduction to digital wireless communication, it’s an extremely simple build using only 17 components on a board compatible with the Microduino. The software is built around something called MinimalProtocol1, a protocol that will be received by all other listening stations, features error correction, and automatic data compression. There’s also the ability to send TCP/IP over the link, which allowed [Mark] to load up our retro site at a blistering 1200 bps.

The code is extremely well documented, as seen on the Github for this project, with board files and even breadboard layouts included. [Mark] has three PCBs of his prototype left over, and he’s willing to give those out to other Hackaday readers who would like to give his modem a shot.

Recycled Foam Box Is Now A Weather Station

May 5, 2014 by Will Sweatman 20 Comments

Raspberry pi in foam box

When [Ioannis] received some high resolution LCD’s in a tattered foam box, he posed to himself a most interesting question – Should he throw the foam box away, or use it as a container for a project? Fortunately for us, he decided on the latter and threw together a very capable weather station!

Having only an hour to spare, [Ioannis] grabbed a Raspberry Pi, WiFi USB stick and a camera module and went to work. He mounted the camera module to the foam lid using a highly advanced technique, and soldered a cable that would power the device directly to D17 – a Zener diode that sits on the bottom of the board.

For the weather data, he’s using another design of his – the Sensor Stick. This nifty device — which we featured over the weekend — is about the size of a stick of chewing gum, and sports an array of sensors including the popular BMP085, which can measure pressure and temperature .

He wraps up everything using open source software to get the data from the weather station. Pretty impressive for an old foam box and an hours time! This would be an interesting start to a home automation system. Connect it to motorized windows and/or a sprinkler system and he’s on his way to claiming The Hackaday Prize.

Raspi, GPS, USB hub and battery hooked together

NSA Technology Goes Open Hardware

May 2, 2014 by Will Sweatman 27 Comments

When [Edward Snowden] smeared the internet with classified NSA documents, it brought to light the many spying capabilities our government has at its disposal. One the most interesting of these documents is known as the ANT catalog. This 50 page catalog, now available to the public, reads like a mail order form where agents can simply select the technology they want and order it. One of these technologies is called the Sparrow II, and a group of hackers at Hyperion Bristol has attempted to create their own version.

The Sparrow II is an aerial surveillance platform designed to map and catalog WiFi access points. Think wardriving from a UAV. Now, if you were an NSA agent, you could just order yourself one of these nifty devices from the ANT catalog for a measly 6 grand. However, if you’re like most of us, you can use the guidance from Hyperion Bristol to make your own.

They start off with a Raspi, a run-of-the-mill USB WiFi adapter, a Ublox GY-NEO6MV2 GPS Module, and a 1200 mAh battery to power it all. Be sure to check out the link for full details.

Thanks to [Joe] for the tip!

Solderless Pogo-Pins For Flashing Routers

April 29, 2014 by James Hobson 17 Comments

Solderless Router Pins

Low-cost wireless routers are a dime a dozen these days — but what happens if you need to flash the firmware? Normally you’d have to solder in a serial connection in order to access it, but [Luka Mustafa] had another idea — pogo-pins!

It’s actually quite easy to make a small PCB with pogo-pins and then use a 3D printed bracket or alignment jig in order to make connection. They currently only have designs for a few TP-Links (WR740 and WR741ND) on their GitHub, but more will be added soon. They’ve also included instructions on how to restore firmware on any of these devices with their handy-dandy pogo-pin PCB.

[Luka] is one of the guys behind IRNAS (the acronym is in Slovenian), a non-profit open-source company that makes lots of cool projects. They believe in open-source and sharing technology in order to empower the world.

And if you’ve royally bricked your router it could be possible to unbrick it with a Raspberry Pi!