Custom PC, Issue 194

Custom PC Issue 194My regular Hobby Tech feature provided two opportunities to break out the thermal camera, thanks to a detailed analysis of a range of cooling products for the Raspberry Pi 4 and a review of the Libre Computer Project’s La Frite single-board computer – and there was even time to take a look at Brian Dear’s exhaustive title The Friendly Orange Glow: The Untold Story of the Rise of Cyberculture.

First, La Frite. Funded, as with all Libre Computer Project boards, via crowdfunding, the compact single-board computer is designed to compete with the like of the Raspberry Pi. It certainly has its selling points: there’s a mounting point on the underside for an eMMC storage module, though it uses proprietary mounting holes; there’s a clever midship-mounted Ethernet port to reduce the overall height; and it even comes with the option of a clever two-piece aluminium case that doubles as a heatsink. Sadly, the board’s performance isn’t there, its software support struggles, and despite the name of the organisation its openness is limited to targeting mainstream Linux kernels; the board itself is a proprietary design.

Moving on to the topic of the Raspberry Pi 4, there’s no secret now that the new high-performance processor at its heart runs a little warm. For my analysis of the issue and a look at some potential solutions, a benchmarking workload was executed while temperature and clockspeed were measured and charted – demonstrating handily the loss of performance you get when the system-on-chip begins to heat up.

These data are joined by the same workload while the Raspberry Pi 4 is enjoying the benefits of a range of third-party cooling products: the Pimoroni Heatsink and Fan Shim options, the former running in passive-only and fan-assisted modes and the latter in always-on and software-controlled modes, along with the 52Pi Ice Tower heatsink and fan assembly as supplied by Seeed Studio and running in 5V, 3V3, and wholly passive modes. The temperatures across the run are then charted, while thermal imagery provides a visual insight into how the whole board heats under passive and active cooling.

Finally, The Friendly Orange Glow is a book I’d heartily recommend to anyone interested in the history of a surprising range of modern technologies – from flat-panel plasma displays and multiplayer gaming to Microsoft’s FreeCell. Charting the rise and fall of PLATO, a computer-assisted learning platform now largely forgotten by history, the book is about more than just technology: as its subtitle, The Untold History of the Rise of Cyberculture, suggests, PLATO and those who built and used it were responsible for cultural movements that wouldn’t be repeated elsewhere in the world for decades.

You can pick up the latest issue of Custom PC Magazine at your nearest newsagent, supermarket, or online at the Raspberry Pi Press Store, or grab it in digital form via the usual distribution services.

Benchmarking the Raspberry Pi 3 Model A+

Back in March, the release of the Raspberry Pi 3 Model B+—the Pi 3 B+ to its friends—brought a chance to take stock and review just how far the project had come since its launch via a series of benchmarks. Now the launch of the Raspberry Pi 3 Model A+ brings a bold claim: a dramatic drop in size, weight, and price over the Pi 3 B+, but without any loss in performance.

In other words: it’s benchmark time once again.

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Custom PC, Issue 154

Custom PC Issue 154In this month’s Hobby Tech column I take a good long look at the BBC micro:bit, CubieTech’s latest Cubietruck Plus (Cubieboard 5) single-board computer, and a pack of Top Trumps-inspired playing cards based on vintage computers.

Beginning with the micro:bit, I was lucky enough to be on the receiving end of a press sample when the much-redesigned educational device was finally ready to ship to schools across the UK. Based on the ARM Cortex-M0 microcontroller and boasting integrated Bluetooth Low Energy (BLE), the micro:bit’s main selling point is its excellent support: the web IDE includes four languages suitable for everyone from absolute beginners to experts, there is documentation galore, and the BBC’s TV output includes shows which remind me of the glory days of the BBC Micro and its related programming.

At least, that would be a selling point if the board was actually up for sale. Despite having now mostly fulfilled its promise to ship free micro:bits to all Year Seven pupils in the UK, the BBC has still made no announcement about commercial availability for the educational gadget. Those whose appetites are whetted by the review, then, are best off looking at the CodeBug on which the micro:bit was based, or the new Genuino/Arduino 101 if Bluetooth LE support is a requirement.

The Cubietruck Plus, meanwhile, is an altogether different beast. Kindly supplied by low-power computing specialist New IT, the board is – as the name suggests – a follow-up to CubieTech’s original Cubietruck. The old dual-core processor is long gone, replaced with an Allwinner H8 octa-core chip that blazed through benchmarks with aplomb – and without hitting the boiling-point temperature highs of the rival Raspberry Pi 3.

Sadly, there’s one piece of information that didn’t make it into the review: shortly after the issue went to press, security researchers discovered a debug vulnerability left in Allwinner’s customised Linux kernel which allows any application on the system to gain root permission. Although affecting only selected operating systems, it’s something to be aware of if you’re in the market for an Allwinner-powered SBC.

Finally, the playing cards. Created by start-up 8bitkick following a successful Kickstarter campaign, the deck is nostalgia in a box. The idea is to bring the Top Trumps concept of collectable, trivia-esque comparison gaming to vintage computing: the cards feature everything from the Acorn Atom to the TI-99/4A, plus a joker in the deck in the form of the Raspberry Pi 2 Model B.

The cards are printed with a very high quality finish, but it’s the source of the images that is of most interest: rather than take the pictures itself, 8bitkick has instead scoured the web for images in the public domain or licensed as Creative Commons. It’s no theft, though: while most Creative Commons licenses allow for even commercial reuse if properly attributed, 8bitkick has promised to upload the full deck design to its website for free download and printing.

All this, plus lots of interesting things by people who aren’t me, is only a short trip to the newsagent’s away – or you can stay exactly where you are and grab a digital copy from Zinio or similar services.

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 ÂŁ160, 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.