New in the Swag Shop: big vinyl stickers, just the right size for hiding any logos you don’t like on the front of your laptop, and little vinyl stickers, just the right size to cover up the logo on the Windows key on your keyboard. These things are tough, and have what I understand is called “high-traffic glue” on them to make them stand up to your typing.
There are some other new goodies available this week too: a logo mousemat, and a very swanky rubberised drinks coaster, which goes splendidly with a cup of coffee. Or a glass of your favourite intoxicant.
Update: Daniel’s blog post here provides some more info, including how to install the technology preview on Raspbian today. And Pekka’s blog post here has some very detailed technical information on the implementation of the Weston backend.
If you’re familiar with the Raspberry Pi desktop experience, you’ll have noticed that windows on the desktop can be a bit slower to move around than you’re used to on your PC or laptop. This is because X, the windowing software (or composition protocol) that we use, is not optimised to use the graphics core of the BCM2835, the chip at the heart of the Raspberry Pi. All the work is done by the ARM processor instead, which slows things down and leaves the graphics core twiddling its thumbs. That graphics core is extremely powerful, so we’re working on putting it to good use to fix the issue.
We’ve made the decision to bypass X completely. Over the past few months we’ve been working with our friends at Collabora to implement the open-source Wayland composition protocol on top of the BCM2835 hardware video scaler (HVS). The HVS is a very powerful piece of hardware, with a scaling throughput of 500 megapixels per second and blending throughput of 1 gigapixel per second. It runs independently of the OpenGL ES hardware, so we can continue to render 3d graphics at the full, very fast rate, even while compositing.
Wayland composited desktop with XWayland and native applications.
In comparison to our current X11 desktop environment, Wayland frees the ARM from the burden of stitching together the top level of the composition hierarchy, and allows us to provide some neat features, including non-rectangular windows, fades for windows which don’t have input focus and an Exposé-like scaled window browser (the sort of thing that Mac users will be familiar with). Legacy X applications can still be supported using XWayland. Check out this video from Collabora to see these features in action, and to compare the current state of affairs with the Wayland future. Those non-rectangular shapes? They’re also windows.
We’re still working to improve performance and memory consumption, and don’t expect to be able to replace X11 as our default desktop environment until later in the year, but we will be including a technology preview in our next Raspbian release. Until then, this post on Collabora’s website gives some more background.
As with PyPy, the Raspberry Pi Foundation has funded this work on Wayland; it’s one of the ways we are trying to give back to the open-source community. Obviously, much of the work on this particular project is Raspberry Pi specific, but there’s a large portion of what’s being done, particularly around XWayland and some of the generic effects in Weston, that can be reused on many other platforms.
We’re looking forward to being able to push out the full release in the next few months. We hope you like the look of it!
Last century I spent weeks researching car computers. I wanted mp3s, videos and access to Notepad on the road. I wanted my car to respect and love me, just like KITT loved David. I wanted it to shout, “Right on tiger!” when I achieved an optimum MPG and to flash up encouraging messages like, “Hello Clive, might I say that you are driving very handsomely today” on a heads-up display.
Sadly it was never to happen. The reality was that you needed a PC the size of a coypu in the boot; an industrial 12/240v inverter; a 15″ CRT monitor strapped to your dash; and hawseholes in your bulkheads. And after a week of constant rebooting halfway through Captain Sensible’s Happy Talk, your hard drive failed because of the vibration and your battery discharged for good. (I gave up and bought a 32Mb Diamond Rio and a hi-tech cassette adapter instead.)
Back in the 21st century, Derek Knaggs at Flamelily I.T has made the thing of my dreams: a low cost, low maintenance, general purpose car computer. There are other Pi-based car computers about but we especially liked this one because it’s simple, cheap and it looks like a factory fit. Very smart.
A quick swap of SDs and Raspbmc meets all of your multimedia needs
The Raspberry Pi is stored in the centre console and all wires routed underneath. Audio is fed through the aux socket of the car’s radio so no additional hardware is needed for this. A wifi dongle provides internet connectivity on the move via a mobile phone hotspot.
Neatly tucked away in the console — note the wifi dongle for internet on the move.
Full details including a shopping list are on Derek’s blog. I’m off to make one.
Conservation, hackspaces and Raspberry Pis. And sharks. How could this not be the blog of the day? Gary Fletcher of ZSL sent us this report.
Marine Conservation Camera
ZSL have developed low cost cameras to monitor marine biodiversity in large marine protected areas (MPAs) using the $35 Raspberry Pi single board computers and standard webcams and running opensource Motion tracking software. ZSL reached out to UK hackspaces to help design the cameras and achieved unprecedented economy and features.
Why Raspberry Pi?
Traditionally it has been incredibly difficult to capture events underwater – all of the usual apparatus such as PIR/heat, infrared and ultrasonic sensors simply do not work underwater. The Raspberry Pi literally opened up a new door with its low power consumption and processing power. It allowed us to deploy a solution which really fits the bill and without it would have been very troublesome to achieve!
Each camera was deployed on an anchored buoy. Mounted directly onto the buoys were two solar panels for charging two deep cycle 90Ah lead-acid gel batteries, the aerial, and a waterproof box containing the communications system. This was then connected to a 50m SWA cat-5 cable running down to the pressure vessel containing the camera itself.
The cameras are designed to operate at depths between 20 and 50 meters. Rlab’s (Reading Hackspace) Ryan White suggested basing the design around a clear polycarbonate tube, with machined HDPE end caps secured by threaded rods and double o-rings. One end-cap had a threaded hole which SWA cat- 5 cable was run though, anchored to the inside and then potted. This cable runs the power and communications.
BuildBrighton’s Mike Poutney and Paul Strotten machined the endcaps on their lathe and offered some great technical advice which was very well received.
The outer pressure vessels easily survived a 100m pressure test in a hydrostatic chamber. It should go significantly deeper had the internal structure not failed at that point.
Rlab’s (Reading Hackspace) Barnaby Shearer designed the internal support structure. This was laser cut from 3mm acrylic. The designs were done in 3D in OpenSCAD to check all the components fitted together, then projected into 2d for laser cutting. The acrylic was glued with tensol.
The junction box was 3d printed and then sealed using potting compound and left to dry for some time also forming a mechanical join between the inside and the cable gland.
Attached to the buoy in a waterproof case was a Raspberry Pi to coordinate the communications. This had an Ethernet link to the Raspberry Pi in the pressure vessel. It also had a WiFi dongle running in access point mode to allow easy monitoring and reconfiguration form the research vessel. The Pi also has a serial connection to an Iridium satellite modem so it can stream pictures of the images captured.
The satellite image transfer software was specially developed by Cambridge Consultants and the equipment and satellite bandwidth for this trip was kindly sponsored by Iridium.
Attached to the bottom Pi was an Eve board to provide the Pi a RTC and a temperature sensor. Also attached was Ciseco’s Humble Pi hosting an AVR and a mosfet to to turn the Pi off at night (and critically back on each morning). This Pi wake was developed by Miles and Matt from Ciseco, who make an amazing range of Raspberry Pi and microelectronics and are well worth a look – http://www.ciseco.co.uk/
These boards were slightly modified to handle a HackHD camera via the AVR so we could capture high definition footage as well as stills.
The boards were assembled at Nottingham Hackspace.
The camera used is the Microsoft LifeCam Cinema HD, a cost effective camera conforming to the UVC specification. The only gotcha proved to be that it seems to only respond to a few ‘magic’ exposure settings (5,10,20,39,78,156,312,625,1250,2500,5000,10000,20000), and you have to wait 100ms and reset the brightness after any exposure change.
Rlab (Reading Hackspace), Gary Fletcher and Doug Snead provided a simple command line program to control the camera, and a slimmed down version of MJPEG-Streamer optimized for this camera and with some additional time stamping.
This stream then fed into Motion which starts saving the frames as JPEGs after it detects an event. The JPEGs are then rsynce’d up to the top Pi (backups are always a good thing). ImageMagick then thumbnails and montages the images for efficient sending over the (slow) satellite link.
The project did spur off onto some stereo vision development work with Doug Snead and Gary Fletcher but could not be completed in time for deployment. It was hoped that it would be possible to develop this solution as so it could automatically size the passing fish to add to our conservation data.
Image showing the accurate sizing of a fish tied to the ceiling flapping in front of an oscillating fan.
What did it Look Like
The deepest ever Pi?
At 50 meters deep – could this be the deepest Pi to date?
Where was it Deployed?
The system was tested at ZSL in London Zoo behind the scenes and then went onto to open Ocean tests in the largest marine protected area in the world, the Chagos Archipelago.
Gary Fletcher and Barnaby Shearer test the camera at ZSL London Zoo, behind the scenes
Well as you can see the results speak for itself, but there is still quite a lot of development work to do but once these sentient units are complete, it will offer a low-cost monitoring system that, when deployed as a network, will greatly expand ocean areas that can be observed.
A post from Mr Raspberry Jam himself, Alan O’Donohoe. This one promises to huge and fabulous, and the National STEM Centre is an outstanding venue. I am strangley drawn to joining the trans-Pennine convoy from Preston. “You may have seen that we are holding a big Raspberry Jam in York on Saturday 8th June, 3 weeks today. Tickets are available here. I’ve been working with the folks at the National STEM Centre there to help establish a presence in Yorkshire for Raspberry Jams.… More
These feel lovely when you sharpen them, have a beauteous Raspberry Pi logo at the end, and are made in solid colours from recycled CD cases. Buy some, look funky when you doodle, help fund computing education, and save the planet too – what could be better? Amazingly, we have not yet sold out of our first batch of Babbage the Bear. (He has stayed on the shelves longer than the camera boards, which we find shocking and remarkable.) Get… More
If you’re wondering about introducing your kids to Scratch, but aren’t quite sure where to start, here’s a handy resource for you. Sean McManus, one of the authors of Raspberry Pi for Dummies, has sent me a link to a couple of sample chapters of the book, including the first chapter on Scratch. You’re welcome to download it to find out whether the book’s for you. Raspberry Pi For Dummies PDF Sampler More
Frederik and Ernest Lotter from Blue Horizon Embedded Systems in South Africa are driving from the UK to South Africa via Russia and the Middle East, taking in seventeen countries on their way. They are making the journey in a Land Rover Defender which is fitted with a Raspberry Pi-based distributed light control system. The Raspberry Pi, and their lighting rig design, will be put to the test over 22000km of harsh conditions and rough terrain. The Lotter brothers are experienced… More
You may have noticed that a little while ago, we quietly withdrew Raspberry Pi branded t-shirts from sale. Since then, we’ve been working on a reboot of the store. Shirts have been totally redesigned, and are now screen-printed rather than transfer-printed, which gives a much higher-quality and tougher finish; we’ve also listened to your requests for more colours and thicker material. [Edit to add: a few of you have asked about the larger sizes. At the moment they’re available in… More
Our friends at DesignSpark have produced a really beautiful time-lapse video with one of our new camera boards. It doesn’t start very beautifully, because it was filmed on a day whose start can best be described as “sodden”, but by afternoon the clouds parted and England started to look exceptionally green and pleasant. If you want to skip the rain, fast-forward to 1m46. (There’s a guest appearance from a double rainbow later on, too.) You can find detailed instructions on… More
The camera boards are now available for order! You can buy one from RS Components or from Premier Farnell/Element14. We’ve been very grateful for your patience as we’ve tweaked and refined things; it’d have been good to get the camera board out to you last month, but we wanted your experience to be as good as possible, and we’ve been working on the software right up until last night. Thank you to Gordon and Rob at Raspberry Pi and to… More
Do you remember the distributed denial of service (DDoS) attacks this website was undergoing a few months ago? They made the news (partly because it was just so bizarre to see someone attacking an educational computing charity) – if you want to refresh your memory, see this, this, or this. Pete Stevens, who runs marathons and our hosting company, Mythic Beasts, thought you’d be interested in what he’s been doing to try to ensure this can’t happen again. (Famous last… More
A slightly abbreviated post today – we’ve just driven 380 miles to Phoenix from LA for Intel ISEF, where Eben’s talking tomorrow, and we’re ready to drop. But I was mailed this amazing piece of work this morning, and it really deserves your attention. Andrew Holme is a member of the Systems Group at Broadcom Cambridge. He’s friends with several of Raspberry Pi’s engineers, and he’s been working on a homemade GPS receiver in the evenings for the last few… More
Here’s a guest post from our friend Pete Wood at RS Component’s community arm, DesignSpark. Pete is one of the organisers of the Oxford Raspberry Jams. This post was first published at www.designspark.com. Raspberry Jams are now being held all over the world; I’ve been trying to go to about one a month, and am lucky enough to be in Tokyo for some press and meetings while the Tokyo Jam is on later this month. There’s a list of events… More
There’s a really fantastic piece in Techradar and Linux Format, going into considerable depth to compare, contrast and review five Raspberry Pi operating systems. If you’ve been thinking about trying out a new distro on your Pi, it’s a great place to start. (And well done, Raspbian!) More
eried, 56 seconds ago:
General discussion • SD readonly
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rleyden, 2 minutes ago:
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