Blob-less Raspberry Pi Linux Is A Step Closer

January 14, 2017 by Jenny List 60 Comments

The Raspberry Pi single board computer has been an astounding success since its launch nearly five years ago, to the extent that as of last autumn it had sold ten million units with no sign of sales abating. It has delivered an extremely affordable and pretty powerful computer into the hands of hobbyists, youngsters, hackers, engineers and thousands of other groups, and its open-source Raspbian operating system has brought a useful Linux environment to places we might once have thought impossible.

The previous paragraph, we have to admit, is almost true. The Pi has sold a lot, it’s really useful and lots of people use it, but is Raspbian open-source? Not strictly. Because the Broadcom silicon that powers the Pi has a significant amount of proprietary tech that the chipmaker has been unwilling to let us peer too closely at, each and every Raspberry Pi operating system has shipped with a precompiled binary blob containing the proprietary Broadcom code, and of course that’s the bit that isn’t open source. It hasn’t been a problem for most Pi users as it’s understood to be part of the trade-off that enabled the board’s creators to bring it to us at an affordable price back in 2012, but for open-source purists it’s been something of a thorn in the side of the little board from Cambridge.

This is not to say that all is lost on the blob-free Pi front. Aided by a partial pulling back of the curtain of secrecy by Broadcom in 2014, work has quietly been progressing, and we now have the announcement from [Kristina Brooks] that a minimal Linux kernel can boot from her latest open firmware efforts. You won’t be booting a blob-free Raspbian any time soon as there are bugs to fix and USB, DMA, and video hardware has still to receive full support, but it’s a significant step. We won’t pretend to be Broadcom firmware gurus as we’re simply reporting the work, but if it’s your specialty you can find the code in its GitHub repository. Meanwhile, we look forward to future progress on this very interesting project.

We reported on the partial Broadcom release back in 2014. At the time, the Raspberry Pi people offered a prize to the first person running a native Quake III game on their hardware, sadly though they note the competition is closed they haven’t linked to the winning entry.

At Last, An Open Source Electric Vehicle From A Major Manufacturer

January 12, 2017 by Jenny List 75 Comments

There is a rule of thumb to follow when looking at product announcements at the fringes of the motor industry that probably has something in common with crowdfunding campaigns. If the photographs of the product are all renders rather than real prototypes, walk away. It is said that small volume vehicle production is a space that attracts either crooks or dreamers, and parting with your money to either can be a risky business. So when yet another electric vehicle platform makes its debut it’s always worth looking, but too often the rendered images outnumber anything from the real world and you know you’ll never see one on the road.

It is with interest then that we note an exciting announcement made last week at CES, that the French carmaker Renault are to release an open-source vehicle platform. It is called the POM, and it is based upon their existing Twizy electric buggy platform. If this last point causes you to snort with derision because the Twizy is a tiny and not very fast in-line two-seater with awful weather protection better suited to the French Riviera than an American Interstate, remember that the car itself is not the point of this exercise at this stage. Instead the access to the technology will spark fresh innovation in the open electric vehicle sector that will transfer into better systems for more practical open source vehicles in the future. (Incidentally, we’re told by people who’ve tried the Twizy that it can be something of an unexpected gem to drive. It seems the lowish top speed doesn’t matter in the twisties when you have a low centre of gravity and quite impressive acceleration in a tiny machine.)

Partnered with Renault are OSVehicle, ARM, Pilot Automotive, a manufacturer of automotive accessories, and Sensoria, who will be working on wearable accessories. It’s probable that you won’t see many POMs on the road if you don’t live in a territory that already has the Twizy, but it’s certain you’ll see its technological legacy in other vehicles.

We’ve covered plenty of electric cars in the past here at Hackaday, and this isn’t the first one with an open source angle. We’ve had a very nice Mazda-derived ground-up build, and an astounding home-made hub motor.

SCSI Emulation Of A Rare Peripheral For The Acorn BBC Micro

January 11, 2017 by Jenny List 24 Comments

Mass storage presents a problem for those involved in the preservation of older computer hardware. While today’s storage devices are cheap and huge by the standards of decades ago their modern interfaces are beyond the ability of most older computers. And what period mass storage hardware remains is likely to be both unreliable after several decades of neglect, and rather expensive if it works due to its rarity.

The Domesday Project 86 team face this particular problem to a greater extent than almost any others in the field, because their storage device is a particularly rare Philips Laser Disc drive. Their solution is the BeebSCSI, a small board with a CPLD and an AVR microcontroller providing host adaptor and SCSI-1 emulation respectively for a modern micro-SD card.

An original BBC Domesday set-up. Regregex [CC BY 3.0], via Wikimedia Commons.

1986 saw the 900th anniversary of the Domesday Book, a survey and inventory of his new kingdom commissioned in 1086 by the Norman king of England, William the Conqueror. One of the ways the event was marked in 1986 was the BBC Domesday Project, a collaboration between the BBC, several technology companies including Acorn and Philips, and a huge number of volunteers from the general public and the British school system. Pictures, video, and text were gathered relating to locations all over the country, and the whole was compiled with a not-quite-hypertext interface onto a set of Laser Disc ROMs. The system required the upgraded Master version of the 6502-based BBC Micro, a SCSI interface, and a special Laser Disc player model manufactured by Philips for this project alone. The hardware was expensive, rare, and unreliable, so few of its contributors would have seen it in action and it faded from view to become a cause celebre among digital archivists.

There have been several resurrections of the project over the years, including one from the BBC themselves which you can browse online. What makes this project different from the others is that it strives to present the Domesday experience as it was originally intended to be viewed, on as far as possible the original hardware and with the original BBC Micro interface. Many original parts such as BBC Master systems are relatively easy to source in 2016, but the special Laser Disc player is definitely not. This board replaces that impossible link in the chain, and should allow them to present a glimpse of 1986 in more than just the on-screen information.

If you would like to see an original BBC Domesday Project system, you can find one in action at the National Museum of Computing, at Bletchley Park. Meanwhile we’ve already featured another peripheral from the same stable as this one, the SmallyMouse USB-to-quadrature mouse emulator.

Pumping Up An Antenna From A Stream Of Sea Water

January 9, 2017 by Jenny List 31 Comments

Our Hackaday readership represent a huge breadth of engineering experience and knowledge, and we get a significant number of our story tips from you. For instance, today we are indebted to [sonofthunderboanerges] for delivering us a tip in the comment stream of one of our posts, detailing an antenna created by coupling RF into a jet of sea water created with a pump. It’s a few years old so we’re presenting it as an object of interest rather than as a news story, but it remains a no less fascinating project for that.

The antenna relies on the conductivity of sea water to view a jet of water as simply another conductor to which RF can be coupled. The jet is simply adjusted by altering the flow rate until it is a quarter wavelength long at the desired frequency, at which point it is a good analogue of a metal whip antenna. The RF is coupled at the base by a ferrite cored transformer that clips around the nozzle ejecting the water, and a bandwidth from 2MHz to 400MHz is claimed. If you work with RF you will probably wince at the sight of salt water coming near the RF connector, as we did.

The advantage of the system is that it allows antennas of multiple frequencies to be created at very short notice and using very little space or weight when not in use. The creator of the antenna at the US Navy’s SPAWAR technology organization points to its obvious application on Navy warships. Whether or not the sailors are using these antennas now isn’t clear, but one thing’s for certain, the idea hasn’t gone away. Early last year Popular Mechanics reported on a similar project under way courtesy of Mitsubishi, in Japan.

Continue reading “Pumping Up An Antenna From A Stream Of Sea Water” →

Give Your Raspberry Pi A Good Hammering

January 9, 2017 by Jenny List 196 Comments

One of the features of the Raspberry Pi Zero is that it arrives with no GPIO header pins installed. The missing pins reduce the price of the little computer, as well as its shipping volume. A task facing most new Pi Zero owners has therefore been to solder a set of pins into the holes, and indeed many suppliers will sell you the pins alongside your new Zero.

The British Pi accessories supplier Pimoroni think they may have a solution to this problem, with a set of solderless pins that the user is expected to fit by tapping both pins and Pi with a hammer. Each pin is designed to deform under pressure, and grip the through-plated walls of the hole in the PCB. In reality they are push-fit pins designed to be fitted with a press or a special tool, but since the average Zero buyer will have neither they supply a small laser-cut jig and give instructions to tap carefully with a pin hammer or similar. They have a demonstration as part of their regular Bilge Tank podcast, which we’ve included below the break.

Pins like these can be quite reliable when installed with the proper tools. They are often used in military and aerospace systems. In this case though, we expect that a chorus of you will be limbering up to comment that it would be far better to solder the connector, and we can’t help agreeing with you. Of course this product isn’t really marketed at Hackaday readers. Instead, the target market of a board like the Zero are children. For them soldering may well be a step too far. We can’t help wondering though whether hammer installation will deliver a reliable enough contact, and whether we’ll see a horde of youngsters whose Pi HATs don’t work due to dodgy connectors. Aside from the ones who’ve broken their Zeros with hammering that was a bit enthusiastic, that is.

Continue reading “Give Your Raspberry Pi A Good Hammering” →

Anatomy Of A Digital Broadcast Radio System

January 9, 2017 by Jenny List 33 Comments

What does a Hackaday writer do when a couple of days after Christmas she’s having a beer or two with a long-term friend from her university days who’s made a career in the technical side of digital broadcasting? Pick his brains about the transmission scheme and write it all down of course, for behind the consumer’s shiny digital radio lies a wealth of interesting technology to try to squeeze the most from the available resources.

In the UK, our digital broadcast radio uses a system called DAB, for Digital Audio Broadcasting. There are a variety of standards used around the world for digital radio, and it’s fair to say that DAB as one of the older ones is not necessarily the best in today’s marketplace. This aside there is still a lot to be learned from its transmission scheme, and from how some of its shortcomings were addressed in later standards. Continue reading “Anatomy Of A Digital Broadcast Radio System” →

The Internet Of Dirt, A Texting Plant

January 8, 2017 by Jenny List 10 Comments

We will all at some point have forgotten to water a plant. If we’re lucky then the limp vegetation we return to will magically revive when we rush to water it, if not then we have the shame of an empty plant pot to remind us of our folly.

No matter, you might be thinking, we can bring technology to bear on the problem, and automate it with a microcontroller! [Bonnie] has done just that, with a capacitive soil sensor feeding an ESP8266-based Adafruit Feather HUZZAH, which in turn logs soil humidity data with the Adafruit IO online service. An IFTTT applet monitors the data, and triggers a notification when moisture falls to the point at which watering is required.

The Instructables write-up gives a comprehensive step-by-step guide to the whole process, including the code, so it’s a project that almost anyone could try as well as a basic introduction to using an online service with a piece of hardware. We can’t help asking, though, whether it might have been better to have had the system do the watering rather than merely administer a prod to its fleshy horticulturist creator. Perhaps that’s left to anyone else building one to add as an enhancement.

Quite a few plant watering automation projects have found their way onto these pages over the years, from this one using car parts to a system with an impressively simple valve made by compressing a flexible pipe. The ultimate watering device though has to be this fully autonomous greenhouse robot.