With hundreds of Arduino shields available for any imaginable application, it’s a shame they can’t be used with the Raspberry Pi. Breaking out the Raspi GPIO pins to Arduino-compatible headers would allow makers and tinkerers to reuse their shields with a far more capable computing platform.
The folks over at Cooking Hacks realized a Raspi to Arduino shield bridge would be an awesome device, so they made their own, complete with a software library that allows you to port your Arduino code directly to the Raspberry Pi.
There are a few limitations with the Raspberry Pi’s GPIO headers; the Raspi doesn’t have analog inputs, so the Cooking Hacks team added an 8-channel ADC. Along with analog inputs and the headers required to pop a shield on the board, there’s also a socket for an XBee module.
The software library contains most of the general Arduino functions such as digitalWrite() and digitalRead(). There Serial, Wire, and SPI libraries are also implemented, allowing any device that communicates through UART, I2C, or SPI to talk directly to the Raspberry Pi.
While the Raspi Arduino bridge doesn’t allow for PWM in the same capacity as an Arduino, you’re always welcome to whip up a servo or LED shield for this neat little adapter.
Since the Arduino was launched years ago, many ‘shields’ or add-on boards providing additional functionality have been released. There are hundreds of different shields, from video capture shields to touch screen shields. Now that the Raspberry Pi is out in the wild, it was only a matter of time before a RasPi to Arduino shield bridge was created.
[Omer] calls his bridge ‘Ponte’ and it allows Arduino shields to be used with the incredible horsepower of an embedded Linux system. While [Omer] originally expected to write the RasPi to Arduino software converter himself, but found WiringPi halfway through the build. Of course this build comes just a day after we saw a tutorial on controlling the GPIO pins on the RasPi, and we expect to see similar GPIO-hacking builds in the future.
Right now, the Ponte only supports Arduino Uno-sized shield, so the possibility of an all-in-one RepRap controller using the RAMPS motor driver is impossible for now. We expect that to change very quickly as more people get their RasPis delivered.
There’s really nothing special about this hack. [Craig Hollabaugh] needed an Arduino shield for hosting a Pololu motor driver and making connections to external hardware. What really caused us to spend way too much time reviewing his posts is that [Craig’s] narrative style of documenting the project is delightful, and we’re envious of his electronics lab. That link points to the first of four project pages. The next page is linked at the bottom of each page, or you can find the collection after the break.
[Craig] starts by designing a single-sided shield in Eagle. It’s been years since he made his own PCB, and it takes him about four tries to get the toner transfer right (we’ve also been victim to the wrong mirroring of the resist!). When it comes time to drill for the pin headers [Craig] uses his 3D printer to make a bracket allowing the Dremel to mount to the drill press. There’s a good tip here about buying carbide bits from Harbor Freight; we thought eBay was the only place to get these. Many of us would need to put in a parts order, but this workshop has a well-organized stock of everything he needs. He also has the solder paste and PID outfitted toaster oven to reflow the board. Oh, and when he forgets to add a resistor it’s off the rework station to add one.
See what we mean… one can never have too many tools.
Continue reading “Fully loaded electronics lab makes your projects a breeze”
[Udo] figured out how to turn a bunch of LEDs into a very low resolution camera.
The build is based around [Udo]’s Blinkenlight shield he’s been developing over the past year. The camera operates under the idea that there’s really not much difference between a LED and a photodiode; LEDs can do light emission and detection. In actuality, the LED ‘camera’ isn’t all that different from a linear CCD array, the type of image sensor in flatbed scanners.
After connecting his Blinkenlight shield to his Arduino and computer, [Udo] wrote a sketch that would capture 17 values from his LED camera. These values are shot over the serial connection where high levels of light show up as smaller numbers and low light levels are understood as larger numbers.
[Udo] has been doing a lot of other cool stuff with his Blinkenlight shield, like a persistence of vision experiment and pretending to be [Michael Knight]. Check out the video after the break for a demo of [Udo]’s linear LED camera.
Continue reading “Turning LEDs into a camera”
Reader [Bradley] sent in his ArduiNIX project, an Arduino shield designed for driving nixie tubes. The shield allows the Arduino to drive and multiplex nixie tubes without any additional hardware. These antique-looking displays are commonly hacked into clocks. It takes 9 volts from a wall wart and steps it up to over 200V in order to drive the displays. The shield is capable of multiplexing up to 80 individual elements. He has example code for driving a 6-digit display and a clock on his site. He is selling kits and completed shields too.
Related: Victorian nixie tube clock
TinkerKit is a collection of 20 different sensors and 10 actuators. It’s meant to make prototyping of physical computing devices much quicker/easier. The devices plug into a Sensor Hub Arduino shield. There is also a similar hub board that can emulate a keyboard; it translates sensor input directly to key strokes. It looks like a very ambitious project and it’s still in development. We love the idea though and think the wide variety of components will foster better final designs. The TinkerKit site covers the current component lineup and there’s a demo video embedded below.
Continue reading “TinkerKit, physical computing toolkit”
[Garrett] from macetech has been prototyping shields for the Arduino development platform. Arduino’s have an inexplicable nonstandard spacing between two of the banks of output pins. This means that you can’t use regular perfboard with them. To make the design process quicker, [Garrett] has put together an Eagle file that just includes the male header pins. The file also has a line indicating the tall lower board components so you can avoid creating shorts.