Custom PC, Issue 150

Custom PC Issue 150There’s a bit of a theme to four of the five pages that make up this month’s Hobby Tech column, and with little surprise: I’ve been focusing on the Raspberry Pi Zero, that remarkable £4 microcomputer which is still proving impossible for retailers to keep in stock. That’s not to say it’s entirely Pi-themed, though: I found room for a look at the lovely CodeBug, too.

Naturally, the first thing I had to do when the Raspberry Pi Zero – a fully-functional Raspberry Pi microcomputer, equivalent in specification to the Raspberry Pi Model A+ but with twice the RAM at 512MB and a new 1GHz stock speed for the BCM2835 processor. The fact that the Raspberry Pi Foundation was able to pack all that into a device around half the footprint of the already-tiny Model A+ is impressive enough, but with a retail price of just £4 the Pi Zero is nothing short of revolutionary.

Sadly, my hope that stock issues would be cleared up by the time the issue hit shop shelves proved unfounded: while stock has appeared at the official outlets several times since the Pi Zero launched, it has immediately sold out again – making the device difficult to get hold of and leaving the market rife with sandbaggers flogging the £4 device for anything up to £50 on auction sites. My recommendation: be patient, keep an eye out the official outlets, and don’t reward the sandbaggers with your custom.

With the Pi Zero in hand, I figured a tutorial would be a logical next step. Perhaps one of the most impressive demonstrations of the new form factor’s flexibility comes in turning it into a true random number generator (TRNG) – at least, what Broadcom claims is a TRNG – for a USB-connected server or PC, improving security for a tenth the cost of the nearest off-the-shelf TRNG. While I used the simple method of attaching a USB-to-TTL serial adapter to the Pi Zero’s GPIO header, it’s even possible to create the same device with a single USB cable for data and power by replacing the stock kernel with one tweaked for USB OTG use – a cost-saving trick for another column, perhaps.

Finally, the CodeBug. I’d been planning on reviewing this for some time, but getting my hands on a sample proved tricky until oomlout was kind enough to loan me a unit from the device’s original crowd-funding campaign. Designed for educational use, and the inspiration for the BBC’s much-delayed micro:bit, the CodeBug is a microcontroller with on-board inputs and outputs and a built-in battery connector. Programmed using a modified version of the block-based Scratch language, it’s a great tool for teaching basic computer concepts – and I now have my hands on a few upgrades for the device, which will be appearing in a future issue.

All this, plus a bunch of stuff written by people who aren’t me, can be yours with a trip to any good newsagent, supermarket, or from the comfort of wherever you’re reading this via Zinio and other digital distribution services.

Linux User & Developer, Issue 160

Linux User & Developer Issue 160In this month’s Linux User & Developer, following my regular four-page news spread, you’ll find a review of a device that’s a little out of the ordinary: the NeuG, a true random number generator (TRNG) which costs a remarkably small amount.

When you’re using cryptography, you’re chewing up your system’s supply of randomness – or entropy. Linux, in common with other operating systems, works to fill its entropy pool by sampling a variety of things: traffic coming in on the network port, where you’re pointing the mouse and how fast it’s moving, and even how long it takes you to press particular keys. That’s all well and good for a desktop, but for a headless server it can take a while to fill a depleted entropy pool.

Coupled with the fact that it’s very difficult for a computer to produce truly random output, there’s a market for true random number generators. These devices typically cost a small fortune but use a variety of techniques – ranging from physically breaking down pieces of hardware with high voltages and measuring the resulting changes to pointing a webcam at a lava lamp – to generate a constant stream of high-quality entropy.

Enter the NeuG, which was kindly supplied for test by the Free Software Foundation. While it looks like a flash drive that has lost it’s casing, the device is actually a miniature computer in its own right. Using on-board analogue sensors, the NeuG can generate what is claimed to be a stream of true random numbers – numbers which are then pushed through a conditioning hash and spat out of a virtual serial port. Simply link the NeuG to something like the rngd entropy gathering daemon, and kiss goodbye to entropy exhaustion in even headless or virtualised environments.

I have been extremely impressed with the NeuG, especially given its low $50 cost. While there are cheaper alternatives – such as using a $5 Pi Zero and USB TTL serial adapter to create something similar using the BCM2835’s on-board hardware random number generator module – the NeuG’s free nature, whereby the design and source code are all available for review and modification, make it a great choice where certified security isn’t a requirement.

For the full run-down, including benchmarks, you can pick up the latest issue of Linux User & Developer from your nearest newsagent, supermarket, or electronically via Zinio and similar digital distribution platforms.

The MagPi, Issue 40

The MagPi Issue 40This month’s MagPi, the official magazine of the Raspberry Pi Foundation, is just a little bit special: it is, to my knowledge, the first magazine ever to include a cover-mounted computer. The release of the magazine today also represents the launch of a brand-new Raspberry Pi model: the Raspberry Pi Zero.

I’ve been lucky enough to have been playing with the Pi Zero for some time, having worked on three of the hardware projects you’ll find between the covers of this extra-special issue. After peeling the Pi Zero from the cover, readers will be shown how to solder general-purpose input/output (GPIO) headers onto its otherwise extremely flat face, connect its serial port to a computer for use as a true random number generator (TRNG), and use it with an existing HAT add-on to act as a mood lamp.

The three projects I created for this issue were chosen from a long, long list. The Pi Zero is an exciting device: it features the same specifications as the Raspberry Pi Model A, but in a brand-new form factor a fraction of the size of the original. Naturally, some features have been cut: just like the Model A there’s no Ethernet chip, but there are also no CSI or DSI connectors and no analogue audio or video ports – though composite video is broken out to a solder pad for the adventurous. The ports that do remain have also been modified: the full-size HDMI port is replaced by a mini-HDMI, and the full-size USB port is a micro-USB port which requires a USB On-The-Go (OTG) adapter before it can be connected to standard USB peripherals.

In doing this, the Foundation has created a device that excites me even more than the full-size models. With a production cost so low that it can be cover-mounted on a high-street magazine, it’s now possible to put a full Linux computer in more project than ever before – and with a simple low-cost USB OTG adapter and a Wi-Fi dongle, it can be networked for a total outlay of well below $10. It is, in short, a game-changer, and I look forward to working on many more Pi Zero-related projects in the near future.

If that wasn’t enough, you’ll also find my review of the Tenma 60W Digital Soldering Station which has been my trusty companion in various projects over the last couple of years. It’s always nice to be able to give a device a good, long-haul test before drawing your conclusions and I’ve certainly put the miles in on the Tenma. As I warn in the review a hobbyist doesn’t strictly need a soldering station, but it does make life easier – and the low cost of this unit, purchased from CPC, makes it easy to recommend for those who fancy an upgrade.

All this, plus more – and, remember the cover-mounted Pi Zero – is available in your nearest WH Smith. The magazine itself is also available as a DRM-free PDF download from the official website, licensed under Creative Commons terms, but obviously you’ll have to buy a Pi Zero separately if you want to follow along with any of my projects.

Micro Mart, Issue 1349

Micro Mart Issue 1349It’s been a while since I’ve graced the pages of Dennis Publishing’s popular weekly Micro Mart, with my last being a cover feature on the ARM architecture in Issue 1235 followed by a feature on Valve’s Steam Box console plans in Issue 1251. For this latest issue, I’ve penned a review of the Raspberry Pi 2 single-board computer as kindly supplied by low-power computing specialist New IT.

As the author of the Raspberry Pi User Guide, which will be entering its fourth edition by the end of the year, I can safely say I bring a certain amount of knowledge to the table for this particular topic. The Micro Mart coverage is one of the first print reviews to be published, with a longer review due to appear in my Hobby Tech column in a future Custom PC Magazine issue.

The Raspberry Pi itself, of course, needs little introduction. In its most recent revision, properly known as the Raspberry Pi 2 Model B, the team have replaced the ageing Broadcom BCM2835 single-core ARMv6 system-on-chip (SoC) processor with a specially-designed drop-in replacement: the quad-core ARMv7 BCM2836. The result is a device significantly more powerful than its predecessor, but one for which software to take full advantage of its capabilities is still thin on the ground.

If you’d like to read the full review, Micro Mart Issue 1349 is available in all good newsagents, most supermarkets, or digitally via Zinio and similar services.

Raspberry Pi User Guide, Third Edition

Raspberry Pi User Guide Third EditionThe recent launch of the Raspberry Pi Model B+, a redesign of the popular single-board computer that addresses some issues with the original while doubling the number of USB ports and increasing the size of the GPIO header, unsurprisingly means that there’s a need for a new user guide. As a result, it should come as no surprise that J. Wiley & Sons has published the Raspberry Pi User Guide Third Edition, a revised work that adds details regarding the new Model B+.

Completed earlier this year thanks to pre-release access to a prototype Model B+ provided by the Raspberry Pi Foundation, the latest edition of my book includes everything a reader needs to know about the latest model. The chapter on using GPIO has been updated to include a full pin-out of the new elongated header and details on how best to use the new USB ports have been added. It’s not all about the Model B+, however: there are entirely new chapters in this edition, including one covering basic programming with Minecraft: Pi Edition from Mojang.

The release of this third edition comes surprisingly soon after the Raspberry Pi Second Edition hit shelves, but those who have already purchased the previous edition needn’t panic: unless you have a Model B+ there’s little you desperately need to know that isn’t contained in the previous release, and if you have a burning desire to use Minecraft: Pi Edition you can find a similar tutorial in my recently-published MagBook 21 Brilliant Projects for the Raspberry Pi from Dennis Publishing – along with, as the title suggests, another 20 projects that you won’t find in the User Guide.

The Raspberry Pi User Guide Third Edition is due to arrive in stock at most outlets within the next couple of weeks, with Amazon UK taking pre-orders for a 19th of September delivery date. If you can’t wait that long, the Kindle Edition is already available for immediate download. Those buying in other countries or high-street book shops should ask their retailer for ISBN 978-1118921661. As with previous editions, numerous translations will follow in the near future.

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.

Bit-Tech, Raspberry Pi Review

Bit-Tech, Raspberry Pi ReviewHaving finally got my hands on a Raspberry Pi Model B, my first published work on the subject is an in-depth review for Dennis Publishing’s technology enthusiast site Bit-Tech.

Designed to cover the most commonly asked questions – computing performance, graphical performance, software compatibility and suitability as a general purpose PC – the review spans nine pages, and is based on the retail Model B which started shipping to customers at the end of last week.

The section which has proven the most popular is ‘Overclocking,’ a look at whether it’s possible to boost the Broadcom BCM2835 at the heart of the Pi to something above its default 700MHz clockspeed. In short: yes, it is, but by ‘eck it’s risky.

The review, the first to appear on a mainstream site rather than engineering publications allied to production partners Element14 and RS Components, has generated a substantial amount of traffic and comment. Following its publication, the review was re-tweeted by the official @Raspberry_Pi account (56,201 followers at the time of writing,) fellow technology journalist and Gruaniad technology editor Charles Arthur (33,614 followers) and digital trouble-stirrers @YourAnonNews  (569,649 followers.) The review was also linked from the Gruaniad, with a fairly hefty extract, and front-paged on Digg and reddit.

Given the popularity of the Pi, this is far from the last piece I’ll be writing about it. A Linux-oriented review for Imagine Publishing’s Linux User & Developer Magazine is due to appear in the next issue, while pieces in Dennis Publishing’s Custom PC, Micro Mart and on the IT Pro website are planned.

There’s also a secret project in the works – but more about that I cannot say…