Custom PC, Issue 146

Custom PC Issue 146This month’s Hobby Tech column begins with a look at a topic that has been close to my heart for a number of years now: thermal imaging, and how it can be applied to the field of hobbyist electronics and technology review. If that weren’t interesting enough, there’s also a review of the Novena open-hardware all-in-one desktop, and a look at a little-known bug-fix applied to Sinclair’s classic ZX81 microcomputer.

For years, I’ve wanted a thermal camera. Recently, the price of cameras has plummeted and I was finally able to justify – just about – the cost of the entry-level Flir C2. While it takes a while to get used to thinking in resolutions of 80×60 – the total resolution of the Flir Lepton thermal imaging module featured in the C2 – I’ve been having no end of fun capturing thermal data on everything from single-board computers to my cat.

In the column, though, I argue for the application of thermal imaging in the hobbyist realm. With smartphone-connected thermal cameras now available in the low-hundreds, and a broken-out Lepton module the equal of the one found in the C2 available for just £160, a thermal imaging sensor is no longer the preserve of well-heeled professionals. I’ve found mine useful for tasks from finding hot-spots on a board design to spotting heatsinks which were not properly mated to the components below.

When I wasn’t playing with the thermal camera, I was playing with the Kosagi Novena. Born from the mind of noted hacker Andrew ‘Bunnie’ Huang, the Novena is remarkable: it’s a truly open computer, with everything from the firmware through to the board designs being published under an open-source licence. Loaned by UK hobbyist electronics shop oomlout, I was sad to give the crowd-funded Novena back – despite an ARM-based processor outclassed by even the cheapest of x86 laptop parts.

Finally, the ZX81. I’ve been clearing out much of my classic computer collection as I shift to a smaller office, and while I had to get rid of my rather rare Sinclair ZX81 I wanted to record its existence for posterity. From the very original production run, this machine boasted the ‘cockroach’ – a bug-fix for a fault in the ROM implemented in hardware, with a hand-soldered board attached to the top of the system’s CPU. It’s a jarring sight, and one that I was privileged to see in person: only a handful of cockroach-model ZX81s, fixed while the company waited for corrected ROM chips to arrive, exist and they’re all externally identical to non-cockroach models.

All this, plus a wide selection of stuff written by people who aren’t me, is available now from your local newsagent, supermarket, or digitally via Zinio and similar services.

Linux User & Developer, Issue 145

Linux User & Developer Issue 145In addition to my usual four-page news spread this month’s Linux User & Developer magazine includes a review of the SolidRun HummingBoard-i2eX, a powerful dual-core microcomputer designed to be roughly Raspberry Pi compatible.

If my description of the HummingBoard sounds familiar, it should: I reviewed the same device in a head-to-head with the similarly Raspberry Pi-inspired Banana Pi in Custom PC Issue 134. Where that review focused on a hobbyist perspective – given that it appeared in my regular five-page spread, Gareth Halfacree’s Hobby Tech – this review is more tailored for the Linux crowd to better address the magazine’s target audience. The board itself, of course, remains unchanged: a dual-core Freescale i.MX6 processor with powerful graphics is installed alongside a chunk of RAM on a computer-on-module (COM) mezzanine board inserted into a feature-packed expansion board, both being supplied by Jason King at low-power computing specialist New IT.

Little time passed between the two reviews, so there wasn’t any chance for SolidRun to tweak the software. At the time of writing, Android 4.4 KitKat was available alongside a Debian variant which truly unlocked the power of the processor. Most impressive of all, however, is the cross-compatibility: the HummingBoard is based on the Carrier-One, an internal development board used by SolidRun while testing the Freescale chip; the same chip is available in single-, dual- and quad-core flavours in the company’s CuBox-i family of media-centric microcomputers – and the HummingBoard is entirely software-compatible, to the extent of being able to take a micro-SD card out of a CuBox-i and boot it on a HummingBoard without modification.

As to whether the board, which includes mSATA and mini-PCI Express connectivity in addition to the usual USB and GPIO features you’d expect of a Raspberry Pi-alike, is worth the cash, you’ll have to pick up a copy of the magazine to find out. If you do, you’ll also find four pages of the finest news I could cull from the worlds of open software, open hardware, open governance and more – along with the usual monthly event calendar.

You can pick up Linux User & Developer Issue 145 at your nearest newsagent or supermarket, or digitally via Zinio or similar distribution services.

Custom PC, Issue 135

Custom PC Issue 135There’s no tutorial in this month’s Hobby Tech, for one simple reason: the only interesting thing I built this month is actually from a kit, and more suited to a review-format write-up. As a result, you’ll find in the pages of Custom PC Issue 135 a two-page review of the Pi2Go-Lite robot kit, a spread on my visit to the Wuthering Bytes festival in Hebden Bridge, and a review of the surprisingly powerful CuBox-i4Pro.

Starting with the robot, Gareth Davies of UK-based educational electronics concern 4tronix was kind enough to send me an early sample of a Raspberry Pi-powered robotics kit he has put together. Dubbed the Pi2Go-Lite, it’s a cost-reduced solder-it-yourself version of a more feature-filled and pre-assembled Pi2Go design. Despite this, it’s hardly lacking in features: as well as a pair of motors driving wheels with rubber tyres and a metal 360-degree bearing caster at the front, the robot includes numerous sensors including infra-red for line-following and impact warnings and ultrasonic for distance measuring.

The kit was a delight to build, being mostly through-hole components with a small introduction to surface-mount soldering in order to – rather cleverly, in my opinion – mount standard through-hole infra-red sensors on the front edge of the main circuit board. The robot itself is driven from the Raspberry Pi’s GPIO header – Pi not supplied – which is in turn driven by a set of AA batteries. I had great fun with the build, and I’d recommend checking out the review if you fancy a bit of Python-powered robotics yourself.

Wuthering Bytes, as those who follow me on Twitter – or, indeed, in real life – will know, is a maker-themed technology event in Hebden Bridge each year. As with last year’s event, I was invited by co-founder Andrew Back to compère the Friday’s formal talk sessions and then used that to guilt the team into letting me attend the Saturday talks and Sunday workshops for free. Personal highlights of the event included a talk by Sophie Wilson, co-inventor of the ARM processor architecture, on the future of semiconductors and some excellent hands-on workshops on the Sunday – and I’m already looking forward to Wuthering Bytes 2015.

Finally, the CuBox-i4Pro. Kindly supplied by the lovely Jason King at low-power computing specialist New IT, SolidRun’s latest revision of the ultra-compact CuBox concept features an amazingly powerful quad-core Freescale i.MX6 processor. It’s the quad-core variant, in fact, of the chip you’ll find in the HummingBoard I reviewed last month, with SolidRun having worked to ensure software written for one can be used on the other.

For all this, plus various things written by people who aren’t me, you’ll want to either venture to your local newsagent or supermarket or stay in and download a digital copy of Custom PC Issue 135 via Zinio or similar services.

Custom PC, Issue 131

Custom PC Issue 131Continuing my terrifically successful Hobby Tech column this month, I cover the building of an arcade controller for the Raspberry Pi using genuine parts and the board’s handy-dandy general-purpose input-output (GPIO) pins, the Software Preservation Society’s KryoFlux floppy imaging device, review the Matrix TBS2910 mini-PC and offer a preview of the first real competitors to the Pi’s reign: the Banana Pi and the Hummingboard.

First, the Matrix: yes, it’s the same board I reviewed for Linux User & Developer this month, so don’t expect any surprises. It’s still a quad-core Freescale i.MX6 design with pre-loaded XBMC-based Linux distribution, designed for use as an open-source platform to encourage sales of TBS’ digital tuner devices. I was a little more generous this time around, mind, as the majority of Custom PC’s readership use Windows as their primary operating system; as a result, the use of a Windows-only utility to switch operating systems on the Matrix isn’t the no-no that it was for Linux User’s readers.

The KryoFlux is probably my personal highlight from this month’s column. Designed and produced by the Software Preservation Society, a not-for-profit group with no lesser aim than the storage and preservation of every game ever released on almost any computing platform, the KryoFlux is a universal floppy drive controller with a USB interface. Combined with the SPS’ software, it allows very low-level sampling of any floppy disk regardless of format, storing details on the magnetic flux transition timings for later decoding. Oh, and you can write disk images back to fresh media. For a collector with a large quantity of decaying magnetic media surrounding him, it’s an absolute lifesaver – if somewhat expensive for its small component count.

This month’s tutorial focuses on turning some old arcade components into a joystick for a Raspberry Pi-powered games console. It’s actually a lot simpler than you might think: digital joysticks are little more than a set of switches, and fire buttons are single switches; the process is no more complicated than the introductory switch-reading project I wrote for the Raspberry Pi User Guide. Combined with some handy-dandy open-source software, it works a treat – as long as your chosen game doesn’t tax the Pi’s poor 700MHz processor too much, of course.

Finally, the Banana Pi and Hummingboard. Both announced at roughly the same time, the two boards are the first in what I’m sure is to be a long line of Raspberry Pi clones. They’re not slavish copies, however: both bring new features to the table, starting with the promise of more power. The Banana Pi, from Chinese embedded computing specialist Lemaker, boasts an AllWinner A20 dual-core module that offers a rough quadrupling of the Pi’s CPU power; the Hummingboard, previously known as SolidRun’s Carrier One, will be available in models up to and included a Freescale i.MX6 quad-core unit. Add in SATA connectivity and even PCI Express, and you’ve got an interesting pair of designs.

I very deliberately didn’t include a review of either device, however: the Banana Pi’s board design is finalised, but the software is in pre-alpha status and is not comparable to the Raspberry Pi’s years-polished offerings. The Hummingboard, meanwhile, has yet to be fully released with my version being a limited-run single-core developer-only prototype kindly provided by Jason King at low-power computing specialist New IT. The finished version is due soon, and there’s a dual-core mid-range model with my name on it.

All this, plus a bunch of stuff by people who aren’t me, can be yours at your nearest newsagent, supermarket or from the comfort of your own home via digital distribution services like Zinio.

Linux User & Developer, Issue 140

Linux User & Developer Issue 140In this month’s Linux User & Developer Magazine, I take a look at two devices from the world of single-board computers – just for a change. The first is the Wolfson Audio Card, an add-on for the Raspberry Pi that promises to boost its sound capabilities considerably; the second, a quad-core Freescale i.MX6-based machine that tries its hardest to be an open-source set-top box. Plus, as usual, there’s my usual four-page news spread to enjoy.

The Wolfson Audio Card – or Wolfson Audio Board, depending on who you’re talking to – was supplied, as is usual for this kind of gear, by the lovely people at CPC. It’s the same device I reviewed for Custom PC Issue 130, so if you’ve read that review you’ll know what to expect: a piggyback board which takes up the GPIO port at the top-left of the Pi and adds digital audio inputs and outputs, significantly higher quality analogue audio support, a quality high-definition codec and even on-board microphones.

The quad-core SBC, however, is new. Supplied by UK distributor PCI Express – and yes, that’s a very awkward name for which to search – the Matrix TBS2910 is a powerful system based around the Freescale i.MX6 processor. I was especially excited to give this system a try, as the i.MX6 is considerably more powerful than the dual-core systems I’m used to – and, as an added incentive for giving it a thorough examination, will be the basis for SolidRun’s upcoming Hummingboard SBC design.

The Matrix is pretty unique in the market, in the respect that it comes from a company – TBS – more usually associated with digital television equipment. The reason is simple: the device is supplied pre-loaded with an XBMC-based Linux distribution and drivers for the company’s digital tuners, which can be connected via USB or through the on-board mini-PCI Express slot. I can see the latter interesting those who fancy adding new features to embedded projects, but there is a catch: switching to a different operating system requires the use of a Windows-only software utility, which sadly cost the Matrix some points in a review for a Linux magazine.

You can read these, plus coverage of the Hummingboard and its rival the Banana Pi, Google’s adoption of IBM’s Power architecture, more news from the Linux Foundation on its Core Infrastructure initiative and the death of Canonical’s Ubuntu for Android project, in the latest issue of Linux User & Developer in shops now or digitally via Zinio and similar services. Readers in France will be able to read the same in a couple of months as the localised title Inside Linux.