Tag Archive for GPIO

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 165

Custom PC Issue 165This month’s issue of Custom PC Magazine marks a milestone: four years since I started writing my Hobby Tech column. To celebrate, three reviews spanning its five pages: the Ryanteck RTk.GPIO, the Kitronik Micro:bit Inventor’s Kit, and the Pimoroni GPIO Hammer Header – the only piece of electronic equipment I’ve ever reviewed installed with a hammer.

First, the RTk.GPIO. The brainchild of Ryan Walmsley, interviewed back in Issue 129, the RTk.GPIO is designed to bring all the joy of the Raspberry Pi’s general-purpose input-output (GPIO) header to any PC with a free USB port. A surprisingly sizeable red-hued circuit board, the RTk.GPIO includes a Pi-compatible 40-pin GPIO header with pin-out on the silkscreen. A quick pip install of the Python library later, and you can pretty much take any RPi.GPIO program and have it run natively on your Windows, Linux, or macOS machine.

Perhaps the biggest power of the RTk.GPIO is in assisting with the development of software for Pi add-ons, using the extra computing power of a desktop or laptop to make your life easier then allowing you to transfer your program to a real Raspberry Pi with minimal changes once complete. Its only real downside, in fact, is price: it’s more expensive than picking up a Raspberry Pi Zero and turning it into a USB device, though undeniably smoother to use.

The Kitronik kit, meanwhile, is one of a range of add-ons I’ve been playing with for my upcoming Micro:bit User’s Guide. Based around a GPIO expansion board for the micro:bit’s edge connector, the kit comes with mounting plate, solderless breadboard, jumper wires, and all the components you need to work through the included full-colour tutorial book – plus, in the version I picked up, the micro:bit itself, though the kit is also available without for those who already have the BBC’s miniature marvel.

In the years I’ve been playing with hobbyist electronics, I’ve seen these kits go from the most hastily thrown together things to extremely polished collections of hardware – and Kitronik’s kit definitely sits at the right end of that spectrum. There are nits to be picked, such as the lack of a handy plastic parts box for storage and no use of the lovely breadboard overlay sheets that make the Arduino-centric ARDX kit so easy to use, but it’s hard to imagine someone buying the Kitronik kit and being disappointed.

Finally, the GPIO Hammer Header. I’ve long been a fan of Pimoroni’s products, but the Hammer Header is by far both the simplest and the smartest I’ve seen. Designed for anyone who has purchased a Raspberry Pi Zero and wants to make use of the unpopulated GPIO header but who doesn’t fancy firing up a soldering iron, the kit makes use of cleverly-shaped pins which can make a suitable electrical connection purely mechanically.

The kit gets its name from the acrylic jig used for installation: assemble the jig with the Pi Zero in the middle, then give it a few sharp raps with a hammer to push the pins home. Male and female variants are available, allowing you to quickly install headers on both the Pi Zero and compact pHAT add-on boards, and to my surprise both installed quickly, easily, and without a single poor joint – and in a fraction of the time of soldering all 40 pins by hand.

For all this, and more, pick up the latest Custom PC Magazine from your nearest supermarket, newsagent, or digitally via Zinio or similar services.

Custom PC, Issue 156

Custom PC Issue 156The latest installment of my long-running Hobby Tech column for Custom PC is four-strong this month: as well as a two-page review of the Particle Electron GSM microcontroller, you’ll find reviews of the Pimoroni Black Hat Hack3r family of Raspberry Pi add-on boards, vintage computing simulator TIS-100, and a look at open-source laser-cut tool holder designs from Wim Van Gool.

First, the tool holders. I’ve never been known for keeping my workspace neat and tidy, but I’ve found that as long as there is something nearby to slot things in I can be trusted to put things back at least half of the time. Trouble is, pen holders are somewhat ill-suited to smaller tools and dedicated tool holders are expensive. Imagine my joy, then, when I discovered that Wim Van Gool had published design files for a pair of tool holders designed specifically for the sort of compact tools you need for detail electronics work to Thingiverse – and, better still, that they could be cut from cheap medium-density fibreboard (MDF).

The Particle Electron, meanwhile, came to me courtesy a Kickstarter campaign I backed following my delight with the Particle Photon – or, as it was known when I reviewed it back in Issue 132, the Spark Core – Wi-Fi microcontroller. Like its predecessor, the Particle Electron is Arduino-like and powered by Particle’s excellent web-based IDE and cloud infrastructure; where the Photon uses Wi-Fi to connect, though, the Electron uses international mobile infrastructure in either 2G (as reviewed) or 3G flavours. For remote projects where Wi-Fi connectivity can’t be guaranteed, that’s fantastic – but be aware that there are ongoing costs, and that the device is locked down to Particle’s own SIM card (supplied).

Pimoroni’s Black Hat Hack3r boards, meanwhile, are significantly less ‘clever’: at their hearts, the Black Hat Hack3r and Mini Black Hat Hack3r are nothing more than break-out boards for the Raspberry Pi’s 40-pin GPIO header. Designed in-house to speed Hardware Attached on Top (HAT) development and released as a product following considerable demand, the ‘dumb’ break-out boards are nevertheless a treat to use: it’s possible to connect a HAT to any model of Pi minus the Compute Module and still retain access to all 40 pins for additional hardware or debugging purposes, or even to daisy-chain the boards to connect multiple HATs to a single Pi – if you don’t mind hacking around the EEPROM issues that may cause.

Finally, TIS-100. I don’t normally review games, but TIS-100 isn’t a normal game: developed by Zachtronics, the creator of Spacechem and the Ruckingeneur series, TIS-100 gives the player control of a fictional 1980s computer system – the Tessellated Intelligence System – with a simplified instruction set. The task: to rewrite corrupted segments of the computer’s firmware, and in doing so uncover the mystery of what happened to the machine’s last owner ‘Uncle Rudy.’ In short: it’s half-game, half-programming-exercise – and pretty much all fantastic.

All this, plus a wealth of other stuff from people other than myself, is awaiting you at your local newsagent, supermarket, or on digital distribution services such as Zinio.

Linux User & Developer, Issue 167

Linux User & Developer Issue 167This month’s Linux User & Developer includes my review of Pimoroni’s Black Hat Hack3r family of break-out boards, designed for both the mainstream Raspberry Pi and ultra-compact Raspberry Pi Zero single-board computers (SBCs).

While Pimoroni isn’t exclusively focused on the Raspberry Pi platform, it’s no secret that the Sheffield-based company has plenty of ideas in mind for enhancing the popular devices. The Black Hat Hack3r range started out as an internal development tool, designed to make it easier to debug Hardware Attached on Top (HAT) devices – add-on boards which cover the 40-pin general-purpose input-output (GPIO) header on top of the Raspberry Pi – without having to deal with a rat’s nest of cables or easily-knocked debug clips.

The boards are simple at their heart: with no active components, all they do is mirror the GPIO header. A ribbon cable connects the board – available in full-size and a Mini variant designed specifically for the Raspberry Pi Zero – to the Pi’s GPIO header, and the HAT under investigation is connected to the mirrored header. A third header then provides full access to all 40 pins, which opens up a wealth of possibilities: you can add additional hardware at the same time as the HAT, sniff signals coming to or from the HAT for debugging or reverse engineering reasons, or even connect more than one HAT to a single Pi by daisy-chaining multiple boards.

I’ve long been a fan of Pimoroni’s designs, and the Black Hat Hack3rs are no exception to the company’s rule of clever boards with attractive layouts and finishes. To get my full opinion, though, you’ll have to pick up a copy of Linux User & Developer Issue 167 from your nearest newsagent, supermarket, or electronically via digital distribution services such as Zinio.

The MagPi, Issue 43

The MagPi Issue 43It’s a special week for the Raspberry Pi Foundation: it’s celebrating its fourth birthday with the launch of the new Raspberry Pi 3. It’s a special day for me, too: the latest MagPi magazine boasts a total of thirteen pages of my content, including the cover splash: a detailed and thorough look at the new model.

Boasting on-board Wi-Fi (a community request since the original model launched four years ago), Bluetooth 4.1, Bluetooth Low Energy, and a faster 64-bit ARMv8 processor, the new Pi 3 is a bit of a beast. My cover feature for the magazine begins with a look at those behind it with a double-page spread featuring interviews with project co-founder Eben Upton and the Foundation’s director of hardware and the man responsible for circuit design James Adams – and a massive thank-you to both for sparing the time to talk to me at one of their busiest ever periods!

The feature then moves on to a look a the board itself, with a hero photo of the board spread across another two pages. Each major feature of the board, from the shiny new 64-bit BCM2837 system-on-chip (SoC) processor to the BCM43438 radio module – which required me to get out the microscope in order to capture its markings – has a call-out with close-up photography and an explanation of how it has changed since the Raspberry Pi 2.

Next up is a benchmark spread, which required me to come up with a detailed suite of tests. After some experimentation, I settled on a selection of classic benchmarks – SysBench CPU in single- and multi-threaded modes, Linpack with and without NEON support, Whetstone, Dhrystone, SysBench memory read and write, Ethernet throughput, Quake III Arena timedemo performance, and power draw at load and idle. As an added bonus, I also came up with a way of measuring general-purpose input-output (GPIO) performance under Python, writing a simple benchmark to toggle a pin on and off as quickly as possible and measuring the speed with a frequency counter connected to the GPIO header.

The next double-page spread looks at helping the reader get started with the new device. I walk readers through modifying an existing Raspbian installation to boot on the Pi 3 by editing config.txt, setting up the Wi-Fi module, enabling true OpenGL acceleration on the graphics processor, and how to write programs to get the best performance on the Pi 3. Sadly, I was unable to explain how to use the Bluetooth 4.1 and Bluetooth Low Energy features, as software support was not available at the time of writing.

The spread then ends with a look at five things you could do with a Pi 3 in order to take advantage of the new features and boosted performance. My work for the magazine continues, though, with a review of the Proster VC99 multimeter and Pimoroni pHAT DAC, before coming to a close with a one-page news piece regarding the production status of the popular Raspberry Pi Zero – helping to explain why it has been so difficult to get hold of and settling concerns that it may be bumped to the back of the production queue now the Pi 3 is out.

All 13 pages of my content, and plenty of other stuff by people who aren’t me, are available from your nearest supermarket or newsagent, or as a free PDF download under a Creative Commons licence from The MagPi’s official website.

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.

Linux User & Developer, Issue 159

Linux User & Developer Issue 159My review for this month’s Linux User & Developer Magazine is the frankly impressive CompuLab Fitlet miniature PC, which joins my usual four-page news spread between the publication’s ever-colourful covers.

I first reviewed the Fitlet in Custom PC Issue 148, published last month, but where that review focused on the device’s suitability for the hobbyist and for general-purpose computing my version for Linux User naturally takes the perspective of a die-hard Linux… well, user. As a result, the fact that CompuLab supplied it with a pre-installed version of Linux Mint 17.2 was a bonus – although there’s nothing to stop you wiping the system and installing any other flavour you fancy, thanks to its entirely standard architecture.

Traditionally, driver support in Linux has always been a pain when it comes to shiny new hardware. I’ve lost count of the number of times I’ve had a device on the test-bench and found that it requires a bleeding-edge kernel or an array of patches to even boot – but not so the Fitlet. Everything, from the wireless to accelerated graphics, was working just fine out-the-box with the sole exception of the General Purpose Input-Output (GPIO) header – an oversight the company has since corrected with the release of an official SDK.

The sheer array of options on offer is enough to turn anyone’s head, too. Those who like an uncluttered desk will find the VESA bracket accessory a must-have; others might find the DIN rail mount a better choice; still more could opt for the larger passive heatsink to overclock the CPU – a one-setting feature directly in the BIOS, requiring no modification and with no effect on warranty – to wring some more performance out. It’s even possible to spec the Fitlet with different ports thanks to its modular Function And Connectivity Extension T-card (FACET) system: the dual-Ethernet single-eSATA default can be quickly modified to quadruple-Ethernet, if that’s your sort of thing.

It’s fair to say I’m a big fan of the Fitlet, and to read the review in full – plus all the latest happenings in the world of open source – all you need do is head to your nearest newsagent or supermarket, or download the issue digitally via Zinio or similar services.

Custom PC, Issue 148

Custom PC Issue 148My regular Hobby Tech column is undeniably review-heavy this month, with three separate items spread across its five pages: the CompuLab Fitlet, the Bare Conductive Touch Board Starter Kit, and the Widdop.

To deal with the latter first, the Widdop is a bit of an odd thing to review at first glance as it was available exclusively to those who attended this year’s Wuthering Bytes festival. There’s method in my madness, though: it’s a variant of the Cordwood puzzle designed by Saar Drimer at Boldport, and a review of the Widdop is equally applicable to its predecessor. In short, it’s a soldering kit sans instructions: two artistically designed and matching circuit boards are supplied along with a fistful of components, and it’s up to the user to not only work out how it should be assembled but then how to interface it to a microcontroller or other controlling system – great fun!

The Bare Conductive Touch Board, by contrast, is readily available. I had previously experienced the delights of the Touch Board, an Arduino-compatible microcontroller with built-in capacitive touch sensing and audio playback capabilities, at the Manchester MakeFest where the Manchester Arduino group were demonstrating Touch Board-powered musical food bowls. The Starter Kit, though, is something else entirely. Packed in an oversized box it contains everything you need to get started, from the conductive paint which made Bare Conductive famous to the Touch Board itself pre-loaded with a voice-led 12-step tutorial.

The booklet is the real prize, though. Walking the user through three projects, it’s one of the best I’ve seen: well produced with exciting photographs and a great attention to detail. The primary project, too, is innovative: a stencil and overlay in the shape of a house demonstrates how the conductive paint can be used to create interactive art, with the remaining two projects offering an intruder alarm – for bare-footed intruders, at least – and a look at adding interactivity to household objects.

Finally, the Fitlet. I’ve been a fan of CompuLab’s tiny Linux-compatible PCs for a while, but the Fitlet is the first I’ve had a chance to review. Supplied in its top-end form with an AMD A10-Micro6700T quad-core processor, it has the grunt of a low-mid-range office desktop but in a passively cooled form factor little larger than a cased Raspberry Pi. Compared to the already diminutive Intel NUC, it’s absolutely tiny: the smallest NUC has a volume of 0.417 litres, while the Fitlet is just 0.215 litres in volume.

Despite its size, there’s a bit of everything: as reviewed, the Fitlet offers on-board Wi-Fi and Bluetooth, dual gigabit Ethernet ports, three USB 2.0 and two USB 3.0 ports, powered eSATA, and even a GPIO connector – which, sadly, lacked driver support at the time of my review, an issue CompuLab has now resolved with the release of an official Software Development Kit (SDK). Running Linux Mint 17.2 but compatible with most any operating system that would run on an x86-64 desktop, the CompuLab is definitely one of the most exciting devices I’ve had the privilege to test recently – although that excitement is tempered by a £300 selling price in the UK, putting it on-par with the more computationally powerful Intel NUC.

All this, plus interesting stuff written by people who aren’t me, can be found between the covers of Custom PC Issue 148 at your nearest newsagent, supermarket, or from the comfort of your own home via digital distribution services such as Zinio.

Custom PC, Issue 141

Custom PC Issue 141If you’re a fan of my work, this month’s Custom PC magazine is going to be something of a treat: as well as the usual five-page Hobby Tech column, I’ve penned an eight-page special cover feature on the Raspberry Pi 2 single-board computer.

The special blends nicely into Hobby Tech itself: a two-page review of the Raspberry Pi 2 straddles the two features, leading in to a two-page round-up of the best operating systems available for the Pi – along with a preview of Windows 10, coming to the platform in the summer. Four pages of tutorials then follow: turning the Raspberry Pi 2 into a media streamer, a Windows- and Mac-compatible file server, and getting started with Canonical’s new Snappy Ubuntu Core and its innovative packaging system.

The next page walks the reader through a series of tips-and-tricks to help squeeze the most from the £30 marvel: overclocking the new quad-core Broadcom BCM2836 processor, built specifically for the Raspberry Pi 2 and offering a significant improvement over the single-core original BCM2835; expanding the capabilities of the Pi’s general-purpose input-output (GPIO) header; setting up a multi-boot platform to try out different operating systems; and updating the firmware and kernel modules to the very latest revisions using rpi-update.

Finally, the feature finishes with a single-page round-up of the best and brightest rivals to the Raspberry Pi’s crown: Lemaker’s Banana Pro, a dual-core Pi-compatible device with impressive operating system options; the SolidRun HummingBoard, a computer-on-module (CoM) design which promises future upgrade potential; the CubieTech Cubieboard 4, which packs an octa-core processor; the low-cost Hardkernel Odroid C1, the only entry in the list I haven’t personally tested; and the Imagination Technology Creator CI20, which bucks the trend by packing a MIPS-architecture processor in place of the more common ARM chips.

The remaining three pages of my regular Hobby Tech column – which celebrates its second birthday with this issue – feature an interview with local game devs Kriss and shi of Wetgenes regarding their clever Deluxe Paint-inspired pixel-art editor Swanky Paint and a review of Intel’s diminutive Atom- and Quark-powered Edison development platform.

All this, plus a smaller-than-usual amount of stuff written by people who aren’t me, can be yours from a newsagent, supermarket, via subscription or digitally via Zinio and similar services.

Raspberry Pi: 21 Brilliant Projects

Raspberry Pi: 21 Brilliant ProjectsA few months ago I was approached by PC Pro’s Priti Patel with a project proposal: a MagBook featuring a number of interesting projects for the low-cost Raspberry Pi microcomputer. I, naturally, jumped at the chance, and the fruit – pun entirely intended, I’m afraid – of my labour is now available.

Entitled Raspberry Pi: 21 Brilliant Projects, the MagBook features 141 full-colour pages of projects designed for beginner to intermediate users. The introductory projects are, as you might expect, gentle indeed: unboxing and connecting the Pi, installing an operating system via the New Out-Of-Box Software (NOOBS), and the like. From there, the MagBook then covers four project categories: Productivity, Entertainment, Plug-In Hardware and DIY & Advanced.

In the Productivity chapter, I walk the reader through safely overclocking the Pi to boost its performance, sharing a keyboard and mouse with a desktop without the need to move any cables, using the Pi as a thin client for a desktop or laptop running Windows, OS X or Linux, setting up a TOR proxy, and installing and running the popular WordPress blogging platform.

In Entertainment, readers see how to convert any TV with HDMI, DVI, SCART or composite video inputs into a smart TV, work with Minecraft Pi Edition, emulate vintage gaming platforms, and build a headless Internet radio receiver.

For the Plug-In Hardware chapter, I wrote up how to build a digital photo frame, the use of USB-connected application-specific integrated circuits (ASICs) to mine Bitcoins, a Twitter-powered motion-sensing security system, how to configure the Pi for fully wireless use, and how to combine the power of the Pi with that of the Arduino microcontroller.

Finally, in the DIY & Advanced section, the reader learns how to use the Pi’s general-purpose input-output (GPIO) capabilities to build a traffic light system, create a doorbell that sends Twitter messages when activated, drive motors for a robotics system, build a custom arcade controller, create an Internet of Things printer, and how to cluster multiple Raspberry Pi units together to boost performance.

The MagBook is available in supermarkets and newsagents now, and will soon start shipping from Amazon UK for £9.99.