This is a portfolio site for Gareth Halfacree, the former systems administrator currently earning a living as a full-time technology journalist and technical author. You may know him from his best-selling books the Raspberry Pi User Guide, The Official Raspberry Pi Beginner’s Guide, and the Official BBC micro:bit User Guide, or his contributions to national magazines, radio programmes, and publications including Imagine Publishing’s Genius Guide and Tips, Tricks, Apps & Hacks series – or even his eponymous “Gareth Halfacree’s Hobby Tech” feature, a five-page spread in Raspberry Pi Press’ Custom PC Magazine each month.
This month’s Hobby Tech column for Custom PC Magazine takes a look at the hidden costs of stereolithographic (SLA) 3D printing, the RISC OS Direct operating system for the Raspberry Pi, and Steven K. Roberts’ classic memoir Computing Across America.
The 3D printing feature was born of a personal cost – literally, money I spent after diving head-first into the world of SLA 3D printing having been tempted by a low-cost entry-level printer. While the printer itself cost around £150, I spent as much again on the accessories required to get good results – from resin and cleaning tools to an ultraviolet curing station and the FEP sheets which form the bottom of the resin vat.
While the feature focuses on SLA printing, which uses a resin cured by exposure to ultraviolet light, there are costs associated with the more common FFF 3D printers too – including finding ways to protect the plastic filament they use from moisture.
Any readers of a certain vintage will likely remember the original RISC OS, an operating system developed initially for Acorn’s Archimedes family then for the later Risc PC. While Acorn itself went away, RISC OS didn’t – and the launch of the original Raspberry Pi, powered by Arm technology which started life at Acorn, gave it a shot in the arm.
RISC OS Direct is an effort to take the modern RISC OS and make it approachable for newcomers, rather than experienced RISC-takers. As a result, it includes a selection of applications pre-installed – from word processors to web browsers – and a handy-dandy wallpaper which doubles as a quick-reference guide. More detailed documentation is also provided, including electronic copies of programming manuals, for those who want to dive deeper.
Computing Across America, finally, isn’t a new book: It was published in the 1980s by Steven Roberts, the self-styled “high-tech nomad” who sold his house and possessions to cycle across America on a custom-built “Winnebiko” with little more than a TRS-80 Model 100 microcomputer for company. While now out of print, the title is available to borrow from The Internet Archive – and makes for fascinating, if often salacious, reading.
Custom PC Issue 207 is available now at all good supermarkets, newsagents, and online with global delivery from the official website.
This month’s Hobby Tech feature takes a look at the recently-unearthed Nine Tiles prototype ROM for the ZX Spectrum by installing it on a ZX Spectrum Next, dramatically improves the flexibility of the FLIR ETS320 thermal inspection camera, and pores over classic computer commercials courtesy of coffee-table tome Do You Compute?.
First, the prototype ROM. In my review of the ZX Spectrum Next in Custom PC Issue 202, I mentioned that it’s possible to create new “machine personalities” – both by replacing the read-only memory (ROM) files used in Spectrum mode and by loading new cores onto the FPGA at the machine’s heart. Shortly prior to the ZX Spectrum Next’s launch, the Centre for Computing History received a trove of artefacts from Nine Tiles – including a prototype ZX Spectrum which was used to develop a ROM which never actually made it onto the publicly-launched machines.
The Centre had negotiated to make the ROM image available for free download for educational and academic purposes, which gave me an opportunity to load the ROM onto the ZX Spectrum Next and create the Nine Tiles Prototype as a usable machine personality. What followed was a process of debugging and reverse-engineering in order to make the ROM functional on the Next – a process which, I’m pleased to say, was wholly successful.
The FLIR ETS320, meanwhile, was reviewed back in Issue 201 – and one of my biggest complaints was its incredibly short focal length, meaning that it is only possible to analyse a very small part of a given circuit board under the thermal sensor. While the camera platform is capable of rising up, anything above 70mm away from the device on test is too blurry to be of use – unless, that is, you take advantage of a 3D-printed tool to manually adjust focus. The improvement is stark, as thermal images published in the piece demonstrate.
Finally, Do You Compute? is a book which looks not at the history of computing but at the history of selling computing – specifically, as the subtitle makes clear, “from the Atomic Age to the Y2K bug.” Put together by Ryan Mungia and Steven Heller, the book is a fantastic chronological walk through the shift in computers being for governments and big businesses to any businesses and eventually the home user.
It also has a major flaw, and it’s not one caused by the authors: Apple, for reasons unspecified, declined to provide permission for its adverts to be reproduced in the book. With Apple having been at the very forefront of the personal computing revolution, and well-known for iconic adverts from its 1984 Superbowl commercial to “Think Different” and “Rip Mix Burn,” it leaves a real hole in the book.
Custom PC Issue 206 is available now in supermarkets, newsagents, and online with global delivery via the official website.
This month’s Hobby Tech column opens with a look at the Raspberry Pi High Quality (HQ) Camera Module, Seeed Studio’s impressively feature-packed Wio Terminal development board, and Read Only Memory’s follow-up to game developer interview collection Britsoft, Japansoft.
First the Raspberry Pi HQ Camera Module. The third full revision of the Camera Serial Interface (CSI)-connected low-cost camera add-on for Raspberry Pi and compatible single-board computers – after the original Raspberry Pi Camera Module was replaced with a higher-quality Sony sensor upgrade – the HQ Camera Module is built around a 12.3-megapixel Sony IMX477 sensor, offering increased resolution and improved low-light performance.
The biggest change, though, is that the lens has gone: Instead of a small plastic lens pre-fitted to the sensor, the HQ Camera Module accepts C- and CS-mount lenses – the same type of lens you’d find for security camera sensors. Two lenses make up the official offerings – a 6mm wide-angle and a 16mm telephoto – with third parties selling various alternatives including microscope-style macro lenses.
The Wio Terminal has a sensor of its own, but it’s not a camera: it’s an almost-all-in-one development board built around Microchip’s ATSAMD51 system-on-chip. Packed into a plastic housing with 2.4″ 320×240 colour LCD, the development board includes buttons, joystick, buzzer, LED, light sensor, and an infrared emitter – but, oddly, no battery, which needs to be added using an external accessory which considerably increases the device’s bulk.
Perhaps the most interesting feature of the Wio Terminal, though, is its general-purpose input/output (GPIO) header: a 40-pin female header, it shares the Raspberry Pi pinout and allows the Wio Terminal to act as a standalone device or to be connected to a Raspberry Pi as a Hardware Attached on Top (HAT)-style accessory – though doing so without some kind of extension cable covers the sensors on the underside.
Finally, Japansoft is a follow-up to the impressive Britsoft which follows exactly the same format: selected bite-sized extracts from interviews with notable game developers, only this time – as the name implies – looking at the Japanese games industry rather than the British. Where Britsoft culled its material from interviews carried out for the 2014 documentary From Bedrooms to Billions, Japansoft isn’t an original publication either: everything within comes from John Szczepaniak’s The Untold History of Japanese Game Developers and is simply reformatted to match the style of Britsoft.
That’s not to say Japansoft isn’t worth reading, but it does mean that anyone who has already seen Szczepaniak’s work will find nothing new. It also makes no effort to fact-check any of the claims within, instead placing a warning that its contents do not represent “a verified factual account” of the history presented.
Custom PC Issue 205 is available now from all good newsagents, supermarkets, and online with global delivery from the official website.
In my Hobby Tech column this month I go hands-on with the Raspberry Pi 4 Model B 8GB single-board computer, the considerably more powerful Nvidia Jetson NX Developer Kit, and take a look at Alex Wiltshire and John Short’s Home Computers: 100 Icons that Defined a Digital Generation.
First, the Raspberry Pi 4. Launched with a view to providing power users with something a with a little more headroom than the 4GB model – itself a fourfold increase on the memory available on its direct predecessor the Raspberry Pi 3 – the new 8GB model doubles the maximum memory while retaining full backwards compatibility. With that said, though, getting the most out of the device does require a 64-bit operating system – and I take a look at third-party options as well as the Raspberry Pi Foundation’s own Raspberry Pi OS in 64-bit builds.
The Nvidia Jetson NX Developer Kit is another device that takes advantage of a 64-bit operating system, but with a very different focus: where the Raspberry Pi 4 Model B 8GB is aimed at hobbyists, the Nvidia Jetson NX Developer Kit looks towards the professional end of the market – and offers some serious GPU horsepower for machine learning work, plus a new “cloud native” software model that containerises workloads to separate them from the underlying OS and to make it easy to run multiple workloads on a single device.
Finally, Home Computers is another in a series of coffee-table tomes investigating early personal computers – but one with a twist: The 100 machines contained within are taken exclusively from The Centre for Computing History in Cambridge. Each is captured in a series of high-quality photographs, including some close-ups and detail shots you won’t find elsewhere, and accompanied with a short write-up of its origins and capabilities. While it would have been nice to see the machines switched on – each is captured in its powered-off state, a shame given the Centre’s reputation as a hands-on “living museum” – it’s still a great book for vintage computing enthusiasts.
Custom PC Issue 204 is available now at the usual stockists, or online with global delivery from the official website.
This month’s Hobby Tech column opens with a look at how the maker and hacker communities are rallying behind the COVID-19 crisis, puts the Rock Pi N10 Model A computer-on-module on the test bench, and takes a look at Imagine That!, the story of APF engineer Ed Smith and his work on the Imagination Machine home computer.
First, the opening spread. The world is still struggling to adjust to a “new normal” in the face of the continuing spread of SARS-CoV-2 and the COVID-19 disease it causes, and nowhere is that more obvious than here in the UK. While many countries have been able to flatten the curve sufficiently to avoid overwhelming healthcare resources, there is still concern over a second wave – and that’s why makers and tinkerers around the world have volunteered their expertise and enthusiasm.
The spread looks at a range of projects currently underway across the globe, from open-source ventilators designed as emergency alternatives to under-stocked invasive ventilators used as a last-ditch treatment for COVID-19 sufferers to homebrew face masks and face shields. Links to each project are included, for anyone looking to get involved.
The Rock Pi N10 Model A is a traditional hardware review: two pages on the computer-on-module. Based on the Rockchip RK3399Pro system-on-chip with integrated neural network co-processor, the entry-level Model A includes 4GB of LPDDR3 memory and 16GB of storage plus PCI Express connectivity for external hardware – a rarity on devices at its price point.
Finally, Ed Smith’s autobiography Imagine That! rounds out the piece. A self-published book, via Amazon’s print-on-demand service, Imagine That! impressed and disappointed in equal measure. For those looking for technical details on Smith’s involvement in APF’s Imagination Machine home computer, it’s a disappointment; for those looking for information on what it was like to be a black engineer growing up in the Browsnville projects in the 1970s there’s plenty of meat in its relatively scant 140 pages.
It’s a topic worthy of publication, but one which will hopefully see enough success to warrant a second edition through a professional publishing house: Smith’s honest storytelling approach is refreshing but scattershot, and riddled with typographical, grammatical, and factual errors begging for an editorial pass, as are the low-resolution and uncredited images sprinkled throughout.
All this, and more, can be found in Custom PC Issue 203, available to buy with worldwide delivery from the official website.
This month’s The MagPi Magazine celebrates the launch of the Raspberry Pi 4 Model B 8GB, the latest single-board computer from the Raspberry Pi Foundation – and the most expensive and highest-specification model to boot.
My cover feature for the launch begins with an overview of the board, which is effectively identical to the previous 1GB, 2GB, and 4GB models bar the memory module in use. With 8GB of LPDDR4 on board, it has twice the memory of its nearest predecessor – and eight times the entry-level model, since pseudo-retired when falling memory prices brought the cost of the 2GB model down to the same level as the 1GB.
The next two pages diverge from my usual launch-day coverage, replacing benchmarks with a dive into the sort of use-cases that could justify moving from 4GB to 8GB of RAM: storage caching, disk-free computing, in-memory databases, virtual machines and containerised applications, machine learning and the like.
The reason for the shift away from benchmarking is simple: in repeated testing the Raspberry Pi 4 Model B 8GB proved absolutely identical in performance to any other model of Raspberry Pi 4, unless the workload exceeded available free memory. While it would have been easy to develop synthetic benchmarks which would show a dramatic improvement in performance for the new model, it would have been misleading to anyone expecting to see a speed boost for day-to-day computing.
From there, the feature moves on to an interview with Raspberry Pi Foundation founder Eben Upton on the timing of the launch – “[it is] absolutely as soon as we can,” he told me during the interview, “the memory packages we’re using are literally some of the first off the production line, a brand-new, shiny memory technology” – the sort of user the new model targets, the Foundation’s work on a 64-bit version of the Raspberry Pi OS which launches in beta today alongside the new board, and the future of the Raspberry Pi 4 range which, sadly, is not likely to include a 16GB model.
The full feature is available to read now in The MagPi Issue 94, available to purchase with global delivery or to download as a free Creative Commons-licensed PDF on the official website.
This month’s PC Pro includes my hands-on review of the TBBlue ZX Spectrum Next, a crowdfunded reimagining of what home computers could have become if the market hadn’t crashed in the mid-80s.
Powered by a field-programmable gate array (FPGA), giving it the ability to transform into anything from a BBC Micro to a Galaxians arcade cabinet, the ZX Spectrum Next is around two years past its original launch schedule. The delay has been attributed to getting everything right, in particular the Rick Dickinson-designed chassis and keyboard – and, in TBBlue’s defence, the entire package is undeniably impressive.
For PC Pro’s testing I went hands-on with a production model of the top-end variant, the ZX Spectrum Next Accelerated. This features 1MB of memory upgradeable to 2MB, which is a lot if you’re thinking in 1980s terms, with a pre-fitted real-time clock and Wi-Fi module to match the mid-range Plus model. The stand-out feature of the Accelerated version, though, is a Raspberry Pi Zero fitted internally to act as a coprocessor – a concept gently borrowed from the BBC Micro and its Tube socket, to which the world’s first Arm processors were connected.
It wasn’t my first experience with the ZX Spectrum Next: I reviewed an early revision of the motherboard, minus case and keyboard, two years ago. In that time, though, the company and the community behind the project have worked to really polish things up: there’s a wire-bound printed manual, though sadly lacking an index; the operating system is swish and the bundled games impressive; the lost 28MHz ultra-fast accelerated operation mode is back, after being dropped in favour of a 14MHz mode following timing issues with the RAM; and while some features aren’t quite ready, in particular the ability to load multiple FPGA cores into a menu and choose from them at boot-up, it’s already a device that will appeal to vintage computing enthusiasts.
This month’s Hobby Tech column opens with a look at the long-delayed but worth-the-wait TBBlue ZX Spectrum Next, moves on to the unique Sega Arcade Pop-Up History from Read Only Memory, and closes on a look at the Raspberry Pi Imager utility.
Issue 202 is not the first time the ZX Spectrum Next, a crowdfunded effort to not only recreate the classic Sinclair machine using modern hardware but to answer the question of what could have been if it weren’t for the microcomputer crash and subsequent sale to Amstrad: the internal hardware was reviewed way back in Issue 176 in the form of the board-only backer reward.
The ZX Spectrum Next is more than just a motherboard, however: its design includes a “toastrack”-inspired chassis and keyboard straight from the drafting board of sadly since-departed former Sinclair industrial designer Rick Dickinson – his last project, it would turn out. The fully-finished hardware, chassis and all, was due to arrive in backers’ hands in January 2018 – but only now, more than two years late, is the hardware finally being delivered.
Thankfully, it’s been worth the wait. Issues with the keyboard’s reliability have been ironed out, errors in the original hardware design resolved, and the firmware which drives the on-board field-programmable gate array (FPGA) updated and tweaked. The 28MHz accelerated mode, missing from the original review, is back, and the custom operating system works smoothly and without issue.
Sega Arcade Pop-Up History is another nostalgia-driven walk down memory lane, but rather than looking at home computers of the 1980s it covers Sega’s “taiken,” or “body sensation,” arcade cabinets – machines which moved to match the on-screen action. The written material is, however, limited: the bulk of the book is given over to card pop-up models of six cabinets, which is a definite first for Hobby Tech.
Finally, the Raspberry Pi Imager. Borrowing shamelessly from Balena’s Etcher, Imager is a tool from the Raspberry Pi Foundation which offers a cross-platform simplified graphical user interface for not only writing disk images to microSD cards but for downloading them too. The flow is just seven or eight clicks long: open Imager, bring up the list of supported operating systems, choose one and confirm, bring up the list of target storage devices and confirm, and flash. There’s even a verification stage, to confirm the image is correctly written – and you can point it at manually-downloaded disk images if your favoured operating system isn’t in the default selection.
All this, and a lot more beside, can be found in Custom PC Issue 202 at all the usual stockists and online from the official website with global delivery.
In this month’s The MagPi Magazine you’ll find my cover feature on working from home using a Raspberry Pi as a fully-functional desktop computer – and, as an added bonus, my photography of the TBBlue ZX Spectrum Next.
First, the cover feature. With a massive explosion in the number of people working remotely worldwide, and the corresponding shortages in hardware and accessories, now is a great time to look towards the Raspberry Pi as a functional alternative to traditional PCs. The six-page feature is split into three sections. The first of these sections looks at installing a Raspberry Pi Camera Module – or the newly-launched Raspberry Pi High Quality Camera Module – or USB webcam and using it for video conferencing via Google Hangouts.
The second section looks at online collaboration platforms, from Google Docs and Google Drive to Slack, Discord, and Firefox Send. The last section takes a look at LibreOffice, the open-source equivalent to Microsoft Office which is pre-installed in Raspbian Linux and fully compatible with the Raspberry Pi. Finally, a sprinkling of tips and tricks complete the feature.
The ZX Spectrum Next review, meanwhile, was written by The MagPi’s editor Lucy Hattersly, but illustrated by me: My hero shot of the ZX Spectrum Next, plus a close-up of the Rick Dickinson-designed keyboard which proved responsible for a two-year delay on the device as it was tweaked for maximum quality and performance, grace the two-page feature alongside a pair of images taken from the ZX Spectrum Next promotional materials.
All this, and more, is available in both the print edition and the free Creative Commons-licensed PDF download from the official magazine website.
This month’s Hobby Tech column takes a look at the upcoming Mooltipass BLE hardware password dongle, FLIR’s ETS320 thermal camera for electronics testing, and has a word from Eben Upton about the cost-reduced Raspberry Pi 4 Model B 2GB single-board computer.
First, the Mooltipass BLE. I reviewed the Mooltipass Mini – itself a successor to the original, bulkier Mooltipass – back in Issue 168: a compact, metal-encased device, the Mooltipass Mini holds your passwords in encrypted storage accessible only using a smartcard and four-digit hexadecimal PIN. I’ve been using the Mooltipass Mini with great success since its launch, but it’s always a bit of a pain to use with a mobile device – requiring a USB cable and OTG adapter.
The Mooltipass BLE aims to fix that, by integrated a Bluetooth Low Energy radio. While it can still operate in tethered USB mode, the Bluetooth radio plus internal battery give it a newfound freedom – though my experience is as a beta tester, with finalised and fully-functional firmware still under active development before the device goes on open sale.
The FLIR ETS320, by contrast, is a fully-finished piece of hardware. Regular readers will know that I’ve long been an advocate of thermal imaging analysis for revealing the secrets of electronic devices, and the ETS320 is a considerable upgrade from my usual FLIR C2: the 80×60 resolution thermal sensor of the C2 is replaced by an impressive 320×240 version in the ETS320, at the cost of a dramatically reduced maximum focus distance. I’d also like to thank FLIR for its partnership: the ETS320 has become a permanent fixture in my toolkit, and will be used alongside the C2 for thermal analysis in future hardware reviews.
Finally, the Raspberry Pi 4 Model B 2GB. While the board itself isn’t new, its pricing is: Raspberry Pi Trading recently decided, prompted by falling RAM prices, to retire the 1GB model and make the 2GB model the new entry point into the family. “2GB is a much more viable desktop platform than 1GB,” RPT chief executive Eben Upton told me in an interview for the column. “1GB is great for embedded, but for a desktop platform it’s just a little bit too tight. What it means is that we’re now back to having a really viable desktop machine at our signature price point.”
The full column is available now in Custom PC Issue 201 at your local newsagent, supermarket, or for global delivery from the official website.