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Linux User & Developer, Issue 160

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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

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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.

Custom PC, Issue 140

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Custom PC, Issue 140In this month’s Hobby Tech column I interview my friend and talented maker Bob Stone, review the ZoomFloppy accessory, and review the Gizmo 2 single-board computer, in roughly that order.

Looking at the interview first, I arranged to quiz Bob after bumping into him at an event a while back. Bob was present as a representative of York Hackspace, showing off a project they had been working on dubbed Spacehack. Inspired by a mobile game, Spacehack gives players the job of keeping a rusty old spaceship in one piece by performing various tasks on a physical control panel which remaps everything between rounds. If that weren’t confusing enough, the instructions that appear on your panel may be for a control on someone else’s – leading to plenty of frantic shouting.

Talking to Bob is always a pleasure, and interviewing him was likewise. He’s a man who knows his stuff and isn’t afraid to inject a little bit of humour into proceedings, and that hopefully comes across in the piece. Having played Spacehack, I can attest to both its difficulty and its brilliance and if anyone local builds their own – the hardware and software are both permissively licensed, naturally – I’d be up for a tournament.

The ZoomFloppy is a natural extension to the KryoFlux I reviewed back in Issue 131. Where the KryoFlux offers a means to connect old-fashioned floppy drives to a modern computer for archival-grade access, the ZoomFloppy is a little different: it’s designed specifically for Commodore devices. Its most common use, as the name suggests, is to provide an interface between a Commodore 1541/1571 floppy drive and a modern PC but it also offers the ability to talk to any Commodore-compatible serial device: printers, plotters, even modems. Better still, you can talk to these devices from directly within an emulator – I couldn’t help but grin when I loaded an Infocom game into the Vice emulator from the original floppy on an 1571 drive.

Finally, the Gizmo 2. I reviewed the original Gizmo in Issue 125 of Linux User & Developer, and was suitably impressed by its performance. The Gizmo 2, I’m pleased to say, blows its predecessor out of the water but isn’t without its own foibles. During my review, I ran into an issue in the firmware which prevented it from booting any device connected into its USB 3.0 ports. Although USB 2.0 worked fine, this had a negative effect on speed – and while the issue was still outstanding at the time of publication, I’m pleased to say a new BIOS has been released as a result of my feedback which fixes the problem and makes the Gizmo a great choice for anyone who needs x86 compatibility and impressive compute performance from a single-board computer.

All this, plus a bunch of stuff written by people who aren’t me, can be yours with a trip to your local supermarket, newsagent, or from the comfort of your own home via Zinio and similar digital distribution services.