Using Arduino Shields With The Raspberry Pi

May 6, 2012 by Brian Benchoff 30 Comments

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.

Controlling Raspberry Pi Expansion Pins With A Web Interface

May 5, 2012 by Brian Benchoff 61 Comments

For the lucky few who have a Raspberry Pi board in their hands, you can now use the GPIO pins as a web interface (German, google translation). [Chris] is turning this magical board is turning a small device that can play 1080p video into something that can blink LEDs via the web.

The build started with an example of driving GPIO pins under Linux. [Chris] cobbled together a bit of PHP and Javascript on the Raspberry pi. Whenever he goes to the website hosted on the Pi, he’s greeted with the status and direction of a couple of expansion IO pins.

On a semi-related note, [Tony] is building a GPIO MIDI interface for his Pi. Yes, he could just get a USB to MIDI adapter and call it a day, but this is a far more professional looking solution to all the MIDI goodness the RasPi will deliver. If you’ve got any info on other RasPi breakout boards you’ve seen, send them in on the tip line.

The First Raspberry Pi Build Is A MAME Machine

March 22, 2012 by Brian Benchoff 28 Comments

The Raspberry Pi was launched nearly a month ago, but these wonderful cheap single-board computers are still on their way from China to the workbenches of hackers and builders around the globe. Although they haven’t shipped yet, plenty of people are chomping at the bit to do something useful with the Raspi. [Nicholas] figured he should hit the ground running, so he emulated a Raspberry Pi to get everything ready for the MAME machine he’ll build when his new toy arrives.

[Nick] found a Raspi VirtualBox image on the official Raspberry Pi forums. After getting a web browser up and running with a few console keystrokes, he turned his attention to a MAME emulator. It’s a relatively simple install (although it did take six hours to compile), but we’re sure the Raspi will be featured in quite a few MAME builds so it was time well spent.

Sure, the Raspberry Pi you ordered a month ago is probably on a container ship in the middle of the ocean right now, but that doesn’t mean you can’t start planning your build. Just load up a VirtualBox image, check out a few of the tutorials, and you’re ready to go.

Raspberry Pi Launched

February 29, 2012 by Brian Benchoff 113 Comments

The Raspberry Pi has been launched. When we first heard of this board nearly a year ago, the idea of a $25 computer that displays 1080p video, runs Linux, and has enough ports to the outside world to do some very interesting stuff, we were cautiously optimistic. Now that the guys behind the Raspberry Pi are getting units out to the masses, we’re a little excited and also thinking about all the cool stuff we’re going to build.

The Raspberry Pi foundation is going with a licensed manufacturing setup with RS Components and Premier Farnell signing up to manufacture and distribute the boards. Right now it’s a strictly one-per-customer situation, but within a month or so you’ll be able to order as many as you would like.

Right now the foundation is focusing on the slightly more expensive ‘B’ model Raspberry Pi that includes Ethernet and USB over the $25 base unit. The ‘A’ model was originally slated to come with 128 MB of RAM, but due to some clever cost saving strategies, the team increased the base RAM to 256 MB.

Right now the only question we have is ~~if an American distributor has signed on~~ to sell this board; we’re sure something awesome will be built with this awesome little board. Commentors pointed out that Newark was selling Raspis for the US market, but they’re out of stock. The best advice may be to wait a few months for production to catch up to demand.

Raspberry Pi Runs XBMC; Reliably Decodes 1080p

January 24, 2012 by Mike Szczys 62 Comments

This is the Raspberry Pi board, an ARM based GNU-Linux computer. We’ve heard a little bit about it, but it recently garnered our attention when the machine was shown running XBMC at 1080p. That’s a lot of decoding to be done with the small package, and it’s taken care of at the hardware level.

Regular readers will know we’re fans of the XBMC project and have been looking for a small form factor that can be stuck on the back of a television. We had hoped it would be the BeagleBaord but that never really came to fruition. But this really looks like it has potential, and with a price tag of $35 (that’s for the larger 256MB RAM option) it’s a no-brainer.

Now there’s still a lot of rumors out there. We came across one thread that speculated the device will not decode video formats other than h.264 very well since it uses hardware decoding for that codec only. We’ll reserve judgement until there’s more reliable info. But you can dig through this forum thread where the XMBC dev who’s been working with the hardware is participating in the discussion.

Don’t forget to peek at the demo clip after the break too.

Continue reading “Raspberry Pi Runs XBMC; Reliably Decodes 1080p” →

Binary Division When Your Processor Lacks Hardware Division

December 1, 2011 by Mike Szczys 27 Comments

[Hamster] wanted to take a look at division operations when the chip you’re using doesn’t have a divide instruction. He makes the point that the divide instruction takes a lot of space on the die, and that’s why it’s sometimes excluded from a chip’s instruction set. For instance, he tells us the ARM processor used on the Raspberry Pi doesn’t have a divide instruction.

Without hardware division you’re left to implement a binary division algorithm. Eventually [Hamster] plans to do this in an FPGA, but started researching the project by comparing division algorithms in C on an AMD processor.

His test uses all 16-bit possibilities for dividend and divisor. He was shocked to find that binary division doesn’t take much longer than using the hardware instruction for the same tests. A bit of poking around in his code and he manages to beat the AMD hardware divide instruciton by 175%. When testing with an Intel chip the hardware beats his code by about 62%.

He’s got some theories on why he’s seeing these performance differences which we’ll let you check out on your own.

Hackaday Links: November 6th, 2011

November 6, 2011 by Mike Szczys 16 Comments

Build details for Raspberry Pi prototype

With the launch of Raspberry Pi approaching the development team released the details about the prototypes from about five years ago. The board was originally based on an ATmega644 and built on some perfboard.

‘Zero Energy Device’ challenge

We call BS on the title of this one, but the goal of finding devices that don’t use disposable energy sources is a good thing in our book. For instance, can we get more stuff that uses long-life capacitors instead of batteries?

Command adhesive for mounting bulletin boards, etc.

This seems like a no-brainer, but we’ve been using nails to mount bulletin boards and white boards for year. The problem is, when you stick a push-pin in one side, the other side pops off of the nail. [Zhanx] is using adhesive from 3M Command Hooks to keep his stuck to the wall.

Servo-driven gripping hand

[Navic] has been hard at work on this robot hand. There’s few details but he shows it can grip objects under one pound and he’s been taking amperage measurement during testing.

Emergency cellphone charging

It might not have been an emergency this time, but [Chris] did figure out a way to charge his cellphone after the snow storm in New England knocked out his power. He connected to lantern batteries to a 7805 regulator, then patched that into a USB hub to get his phone connected. Not bad in a pinch!