[Tod’s] daughter has a habit of forgetting to take a house key along with her, so he was looking for a way to make accessing the house easier in a pinch. He had tried wireless garage door keypads in the past, but their performance was so-so at best. After scouring the market for commercial solutions and checking out the work of other hackers, he decided that he needed to craft a custom solution of his own.
He started shopping around for wireless-enabled microcontrollers and settled on a Roving Networks RN-XV module, which is designed as a drop-in replacement for an XBee. Paired with a 5v to 3.3v power adapter, the RN-XV is nearly all he needed to interface his iPhone with his garage door opener.
The microcontroller has enough GPIO pins to control the garage door, while also monitoring the door’s status using a simple magnet/reed switch combo. A web server in [Tod’s] house takes input from any phone connected to his wireless LAN and relays the open/close commands to the opener. The opener in turn returns status messages to him via the web interface.
We really like the system’s simple design, and as long as [Tod] has turned WPS off at home, he really shouldn’t have to worry too much about unauthorized entry.
Children of the 80s may remember the Big Trak, a six-wheeled programmable toy designed to explore distant planets on the other side of the living room and the vast expanse of a two-car garage. The Big Trak was re-released a few years ago and [Nathan] took quite a shine to this improved version. He was so enthralled he decided to upgrade it even more to support the LOGO programming language.
The 30-year-old version of the Big Trak had a membrane keypad where commands such as ‘drive forward 5 units’ and ‘turn 90 degrees’ can be saved and run from memory. This is very similar to the LOGO programming language with and turtle graphics and nearly identical to the Roamer LOGO robot.
To control the Big Trak, [Nathan] upgraded the electronics to a ChipKit Uno and a BeagleBone. A LOGO interpreter written in Python and uploaded to the BeagleBone. After this, [Nathan] was nearly set. He did add a WiFi interface to control his Big Trak wirelessly, a nice touch we think.
You can check out [Nathan]’s twenty-minute build video where he goes through the entire process of upgrading his Big Trak after the break.
Continue reading “Turning the Big Trak into a Turtle”
Little, no name, 1.5 inch LCD photo key-chains are all over the place for practically nothing. Not too surprisingly these things do not vary much in the parts that they use, some flash ram, a little lipo battery and a 16 bit color LCD. Wanting to find a way to reuse that LCD [Simon] Has an excellent tutorial on how to reuse a FTM144D01N LCD with a ILITEK ILI9163 LCD driver for your electronic projects.
Two units were used, one was ripped apart and soldered to a home made breakout board, the other was kept intact so its logic could be sniffed out with an oscilloscope. A pin-out was quickly determined since these things typically use a 8 or 16 bit data bus. Then a driver library was put together for AVR micro controllers, which includes some basic shape drawing and a 5×8 font.
While you may not be lucky enough to get this exact LCD screen from your local bargain store, there are a lot of pointers in here to hopefully get you up and going. We will be trying our luck on a very similar screen this afternoon as these things do have a decent picture and fairly quick response times already packaged in a hand-held case.
Join us after the break for a quick video.
Continue reading “Reverse Engineering a 1.5 inch Photoframe”
What uses a fire extinguisher, a bike pump, and provides hours of probation, community service, and possibly jail time? If you said an automatic graffiti writer you’re correct! [Olivier van Herpt] calls this little job the Time Writer. We call it defacing property… but tomato, tomahto.
Details are a bit scarce, but you get a fine overview of the system from the video after the break. [Olivier] tagged the post as Arduino; it’s obviously running the dot matrix printer made up of seven solenoid valves on a metal rod. These are fed ink via a tube connected to a fire extinguisher which serves as the reservoir. The bike pump is used to pressurize the enclosure so that a pump isn’t necessary when out and about.
Obviously you shouldn’t try this at home, but let’s talk about possible improvements as an academic exercise. First off the mix of the ink/paint needs to be reigned in to get rid of the dripping. We’d also like to see the inclusion of some proper spray can nozzles to tidy up the results. That, paired with an IMU board should be able to smooth out the printed designs.
This might make an interesting add-on to that rainbow graffiti writer.
Continue reading “Weapon of mass graffiti”
Some of our younger readers will never have experienced this before, but back in the day your video games would slow way down if there were too many moving objects on the screen. The original Castlevania comes to mind, but many will remember the problem while playing the fantastically three-dimensional Super Nintendo game Starfox. [Drakon] isn’t putting up with that hardware shortfall any longer, he hacked this cartridge to run at 42 MHz, twice as fast as the design spec.
We only occasionally look in on the cart hacking scene so it was news to us that three different versions of a pin compatible chip were used in this hardware. The first two suffer from the slowdown problem, but the final revision (SuperFX GSU 2) doesn’t. It can also be overclocked as high as 48 MHz but because of the video frame rate you won’t see added improvement with the extra 6 MHz.
[Drakon] used a Doom cartridge as a guinea pig because it offers the most RAM, and set to work rerouting the traces for the ROM chip to an EEPROM so that the hardware can be used with different games. He also took this opportunity to patch in the faster clock signal.
In the interests of interface archaeology, [Martin] sent in the Tworse Key, a telegraph key that posts to Twitter using Morse code. It’s a fantastic build that nearly looks like something out of the 1900s.
We’ve seen a ton of Morse keyboards over the years, but never one so well-engineered for a single purpose. The guts and brains of the Tworse Key is an Arduino Ethernet that connect to Twitter over the API. The Tworse Key automagically posts all the Morse messages to Twitter. The Tworse Key may have fallen off the table a few times in the past 24 hours, but we do see a few purposeful messages like ‘sos’ and [Bell]’s preferred telephone salutation.
We could say that nobody uses straight telegraph keys anymore, but outside a few hardcore CW HAM radio guys nobody uses Morse anymore. This isn’t meant to be used as an everyday input device, though. It’s more of an exercise in interface archaeology. That being said, an iambic key would be a far more ergonomic solution. Check out the video of the Tworse Key after the break.
Continue reading “Telegraph key makes for a fantastic Twitter input”
As weird as it might sound, there’s a way to use Google documents as a web proxy. The image above is a screenshot of [Antonio] demonstrating how he can view text data from any site through the web giant’s cloud applications. Certain sites may be blocked from your location, but the big G can load whatever it wants. If all you need is the text, then so can you.
The hack takes advantage of the =IMPORTDATA() function of Google Spreadsheet. We guess the command is meant to make import of XML data possible, but hey, that’s pretty much what HTML data is too, right? But what good it the raw webpage code in a spreadsheet? This is where [Antonio] made a pretty brilliant leap in putting this one together. He authored a bookmarklet that provies a navigation interface, hides the raw code which is stored in the spreasheet, and renders it in the browser. This ties together a user supplied URL, reloading data on the hidden spreadsheet and refreshing the window as necessary. See for yourself in the clip after the break.
Continue reading “Using Google documents as a web proxy”