All the projects in the book, the traffic light simulator being no exception, work step-by-step in building the simplest possible incarnation of each then adding increasing complexity – and in doing so introducing new concepts. In the case of the traffic light simulator, it starts off as a simple set of three LEDs which are under timed control.
As the project progresses, the reader adds a button to act as a trigger for a pedestrian crossing – which adds the concept of threading, taking advantage of the second CPU core on the Raspberry Pi Pico’s RP2040 microcontroller – before finishing the project with a buzzer providing audible feedback for when it’s safe to cross.
This month’s The MagPi Magazine carries my six-page guide to getting started with physical computing projects using the newly-launched Raspberry Pi Pico, the first microcontroller in the Raspberry Pi family.
Taken from my book, Get Started with MicroPython on Raspberry Pi Pico: The Official Guide, the tutorial walks the reader through programming the Raspberry Pi Pico using MicroPython – starting with the physical computing equivalent of “hello, world,” lighting up an LED. No additional hardware is needed for this part: the Raspberry Pi Pico includes a surface-mount user-addressable LED at the top of the board.
The reader is then shown how solderless breadboards work, introduced to importing MicroPython libraries and handling delays, how external LEDs require resistors, how to read a button input, and finally how to put it al together into a simple circuit which can toggle the LED based on the user’s button presses.
This month’s MagPi Magazine celebrates the launch of the new Raspberry Pi Pico with my 14-page feature introducing the first Raspberry Pi microcontroller, the first in-house silicon which powers it, and walking the reader through getting started programming the device with MicroPython – as well as talking to three of the people behind the effort.
Built around the RP2040, the first silicon chip produced by Raspberry Pi’s in-house ASIC team, the Raspberry Pi Pico is a fascinating device. While accessible enough for education, thanks to MicroPython support and a breadboard-friendly layout, it’s also designed to work as a module for industrial and embedded projects – and even launches with a port of TensorFlow Lite for machine learning work.
My feature begins with a look at the Raspberry Pi Pico and the RP2040, covering all the major features from RP2040’s programmable input/output (PIO) to the handy single-wire debug (SWD) header at the bottom of the Raspberry Pi Pico. As always, there’s plenty of photography.
The feature then moves on to an interview with Nick Francis, senior engineering manager, James Adams, chief operating officer, and Eben Upton, chief executive officer, covering the work done on both RP2040 and Pico, their hopes for the device, and how it aims to pack a surprising amount of functionality into a £3.60 gadget – “cheap as chips,” Adams told me.
Finally, the feature closes with a series of hands-on tutorials walking the reader through setting the Raspberry Pi Pico up on their Raspberry Pi or other computer, flashing the MicroPython firmware, and working on their first physical computing program.
The latest issue of The MagPi Magazine includes a whopping 12-page feature investigating the thermal performance of the Raspberry Pi 4 Model B single-board computer as it is affected by a series of firmware updates released since its launch earlier this year.
When I reviewed the Raspberry Pi 4 at launch, I highlighted its dramatically increased power draw and heat output compared with its predecessor the Raspberry Pi 3 Model B+. In the months since, the Raspberry Pi Foundation has been working to address the issue through a series of firmware updates – and, with assistance from Eben Upton and Tim Gover, my feature runs through each release and sees what difference it actually makes.
For the feature, I had to develop a method of benchmarking the Raspberry Pi. Power draw was relatively straightforward: the built-in current meter in a bench-top power supply is used to measure the minimal draw at idle and peak draw at load. For thermal performance, I wrote a custom benchmark which uses two open-source utilities – glxgears and stress-ng – to place a heavy load on both the CPU and the GPU while measuring the resulting temperature rise and the speed of the CPU, which throttles at 80°C to protect the silicon.
These measurements provided a graph of temperature rise and fall, the latter thanks to a five-minute cool-down period built into the benchmark, but for a more visual approach I also took thermal imagery of the board at idle and load to demonstrate which components are responsible for the heat output and better highlight the improvements made at each firmware revision. This was no small undertaking: the benchmarking and thermal imagery was completed for five firmware revisions, the last of which was not publicly available at the time of testing, plus a baseline Raspberry Pi 3B+ for comparison.
The feature also takes a look at a real-world workload, in which temperature and clock speed is measured while a four-worker compile of the Linux kernel is carried out. This revealed something which may come as a surprise to critics of the board: Using the latest firmware, the Raspberry Pi 4 did not throttle at all during the compilation – something that can’t be said for the Raspberry Pi 3B+, which throttled to 1.2GHz from 1.4GHz almost immediately. For the final bit of testing, there’s even a comparison of the Raspberry Pi 4 running sat flat on a desk and balanced vertically – at Upton’s suggestion – with a resulting dramatic impact on the throttle point and operating temperature.
Finally, firmware developer Tim Gover was kind enough to answer my questions on what the Raspberry Pi 4 firmware actually does, how it is developed, and how it can have such a dramatic impact on power usage – along with the confirmation that USB mass-storage booting and IPv6 network booting are on the to-do list for future releases.
The full feature, and plenty more beside, can be found at your local newsagent, supermarket, or downloaded at no cost in digital form under a Creative Commons licence from the official website.
There’s no missing my contribution to this month’s The MagPi: it’s plastered all over the cover. The launch of the Raspberry Pi 3 Model A+ ends a four-year absence of the compact form factor from the Raspberry Pi line-up, and there’s no better way to celebrate its launch than with a massive cover feature.
The spread begins with a two-page introduction dominated by imagery of the board, before moving on to a plan view which calls out the individual components that make up the board – including the single USB port, BCM2387B0 system-on-chip (SoC), and the radio which, for the first time in a Model A variant, adds WiFi networking and Bluetooth connectivity. Each part includes macro photography, all taken in my in-house studio.
The next section of the feature runs through a series of benchmarks which, in-keeping with previous launches I’ve covered, compares the Pi 3A+ with other mainstream Pi models going all the way back to the original Raspberry Pi Model B. The feature also includes a look at the size and weight, the first time I’ve used that particular metric, along with comparative thermal imagery showing how the smaller surface area of the PCB copes with running the same high-performance processor as the larger Pi 3B+ – again, all captured in-house.
Finally, the cover feature closes with a two-way interview I conducted with project co-founder Eben Upton and principal hardware engineer Roger Thornton. In it, Eben confirms that the Pi 3A+ represents “tidying up ‘classic’ Raspberry Pi,” and that the Raspberry Pi 4 – still very much on the drawing board – will launch a whole new era for the low-cost single-board computer family.
The launch issue is available now from your nearest newsagent or supermarket in print, or can be downloaded free of charge under a Creative Commons licence from the official website.
This month’s MagPi Magazine includes my first look at FORMcard, a crowdfunded bioplastic which aims to make building and repairing objects as simple as making a nice hot cup of tea.
I’ve long been a fan of Sugru, the mouldable silicone rubber, but FORMcard was new to me when the company reached out to highlight its various features. Supplied in packs of three and in a variety of colours, each FORMcard is a block of plastic the size of three or so stacked credit cards. Out of the box, they do little: they’re slightly flexible, though not very, have the logo embossed on the corner, and could be used as a ice-scraper in a pinch.
Dunk the card into hot water – anything above around 60°C works well – and the secret is revealed: the plastic, a starch-based bioplastic which is claimed to be non-toxic and food safe, softens and melts. Fish it out with a spoon and you can begin to form it into whatever shape you desire: a patch for a broken piece of more traditional plastic, a stand for your smartphone, a cube, whatever.
Unlike Sugru, FORMcard sets in minutes as it cools down; it’s also considerably harder and stronger when set, enough so that you can create a handle for a screwdriver from it. It’s also reusable, which is both a strength and a weakness: it means you can use a FORMcard for a temporary repair, unlike single-use Sugru, but it also means it’s absolutely useless for anything that might reach 60°C or more – including creating cases for hot-running electronics or insulating pan handles, both tasks to which I’ve put Sugru with considerable success.
For my final opinion, and a bunch of other interesting stuff from people who aren’t me, you can pop to your local newsagent or supermarket to pick up The MagPi Issue 51, or download your free Creative Commons licensed copy from the official website.
This month’s MagPi magazine is a little bit special: it’s Issue 50, celebrated with a shiny foil cover in the physical edition. Inside, you’ll find two pieces of mine: an interview with Dark Water Foundation’s Barry Getty regarding his Dark Control motor boards, and a review of the Sugru Rebel Tech Kit which should be heading to shelves in time for Christmas shopping.
I first met Barry at the Liverpool MakeFest event in 2015, where he was running a workshop to build Arduino-based LEGO remote operated submersible vehicles (ROSVs) which could be piloted through an obstacle course installed in a fish tank at the end of the table. When he got back in touch a year later to show off his Raspberry Pi motor control board add-ons, I knew I needed to interview him on the topic.
The Dark Control boards differ from most motor control boards available in their scope: both models, designed for ESC and DC motor types, include six outputs for full freedom of movement. Various extras, including GPIO pass-through and room for additional hardware, are included, and it’s little surprise to find that Barry’s Kickstarter campaign closed with 145 per cent of its goal funding.
The Sugru kit, meanwhile, is something of a passion of mine. I’ve lost count of the number of things I’ve fixed around the house thanks to “mouldable glue” Sugru, and when they got in touch with details of an upcoming introductory kit I jumped at the chance to have a look. The bundle includes a storage tin, guitar pick for moulding, four packs of Sugru, and a full-colour booklet of projects. If you’re familiar with Sugru, there’s nothing there that’s a must-have compared to just buying a plain pack of the stuff, but if you’re introducing others to the wonderful putty that hardens into silicone rubber it’s a fantastic bundle.
Finally, the book review section of the magazine includes a pleasant surprise: a review of my Raspberry Pi User Guide Fourth Edition, in which it is described as “a reference which will become as essential as its three predecessors.” High praise indeed!
The MagPi Issue 50 is available in all good newsagents and supermarkets now, or can be downloaded free of charge in Creative Commons-licensed PDF format from the official website.
The latest issue of The MagPi, the official magazine of the Raspberry Pi Foundation, includes my two-page interview with Grant Macaulay of Theo Lasers, along with what is now rapidly becoming a go-to image I took of a Raspberry Pi 3 artfully rotated and pasted onto the cover.
I first met Grant at the Maker Faire UK event earlier this year, and got talking to him about the project he had quit his job to build: Theo Lasers. Designed to address the lack of affordable entry-level laser cutters and engravers for hobbyist and educational use, Theo Lasers came from a simple idea: “I’m going to make a laser cutter with a laser cutter,” he laughingly explained in front of a stand of prototypes proving he could do just that.
In the months since the event, Grant has been hard at work improving upon his design. In particular, with the aid of a developer friend, he’s moved from basing the hardware on an Arduino Mega microcontroller to using a Raspberry Pi Zero. In doing so his team developed Theo Controller, a browser-based control and monitoring system which runs entirely on the Pi and which can accept input from any web-compatible device. Coupled with an on-board display, SD card reader, and even the ability to run from battery or solar power, and Grant’s design definitely stands out from the competition even before you see its eye-catching wooden chassis.
Grant’s due to launch a Kickstarter campaign to begin mass production of the Theo Laser cutters in early September, with more details available from the official website. The interview, meanwhile, can be read for free in the Creative Commons licensed The MagPi Issue 49, out now.
Following on from last month’s Pi Zero extravaganza, my workload for the latest issue of the Raspberry Pi Foundation’s MagPi was pretty light: a single review, looking at the wonderful Bare Conductive Touch Board Starter Kit.
I actually received and wrote this review some time ago, but various flat-plan changes led to it being bumped from its planned issue with the first suitable gap being in this New Year’s edition – published, as is so often the case with print publications, just before Christmas. Thankfully, the Touch Board isn’t really something that ages, and the model you would buy today is the same as the one I reviewed a few months back.
For those not familiar with the company’s output, Bare Conductive made a name for itself with a conductive paint suitable for making paper-based circuits. This was followed by the Touch Board, an Arduino-compatible microcontroller with built in capacitive touch and distance-tracking sensor capable of playing MP3 audio files from a micro-SD card depending on which of its inputs were triggered. The Starter Kit, then, unsurprisingly brings both inventions together: there’s a pot of the conductive paint plus a tube for more accurate dispensing, a brush, a Touch Board, crocodile clips, a rechargeable speaker, micro-SD, USB cable, and everything you need to build three example projects.
The bundled book is extremely good: printed on quality paper in full colour and with a modern layout, it goes some way to justifying the far-from-impulse near-£100 price point of the kit. So too does the out-of-box experience: MP3 files are pre-loaded on the micro-SD card, and if you connect the touch board to a USB port for power and poke each contact in turn you’ll be given voice guidance through its capabilities and use.
If you want to read more about the kit, the review is available in the free MagPi Issue 41 PDF or in print at newsagents and supermarkets throughout the UK.
This month’s The MagPi, the official Raspberry Pi magazine, is rather special: it’s the first print issue since the community-created publication was taken under the wing of the Raspberry Pi Foundation. While previous issues were available in limited-edition print runs created through crowd-funding efforts, from now on the magazine will be found in major high-street shops as standard – starting with WH Smith. This doesn’t mean the free digital download is going away, though: all content is still Creative Commons licensed, and the PDF download will be available free of charge at the same time as the print issue hits shelves.
Going for the hardware first, local electronics giant CPC was kind enough to send over a box of goodies including the printing pen and some wearable kits – about which you’ll read more in future issues – when they found out I was running low on review hardware. Created by Velleman, a company better known for its test equipment, the 3D Printing Pen is a near-direct copy of the 3Doodler: the extrusion system of a PLA-based 3D printer stripped out of its three-directional housing and placed inside a pen-like grip.
The idea, the instructions explain, is that you can ‘draw’ three-dimensional objects freehand – taking away the complexity and expense of a traditional 3D printer. The remaining technology is simple, and nothing particularly new: you can think of the pen as a glue-gun using plastic in place of glue. The box shows someone drawing a scale model of the Eiffel Tower freehand, but I found it a major struggle to even get my simple cubes and pyramids looking recognisable.
I had a lot more luck with Swanky Paint, created by local coding house Wetgenes. I had previously interviewed the two programmers behind the software back in Custom PC Issue 141, but this time I took their most famous creation in-hand and gave it a thorough testing: Swanky Paint. Available in cross-platform browser-based flavours as well as native versions for traditional PCs, smartphones, tablets, and the Raspberry Pi, Swanky Paint is inspired by EA’s classic Deluxe Paint – the go-to art package for an entire generation of game artists – and shares UI and UX similarities, down to the keyboard shortcuts on offer.
Where Deluxe Paint had its pixels on show due to the low resolution of computing equipment at the time, though, Swanky Paint revels in it. Designed for retro ‘pixel-art’ projects, the software makes everything as easy as possible and includes a surprising level of polish for an early alpha release – including various effects designed to emulate the smoothing glow of a traditional CRT display.
If you want to find out my conclusions on both products, as well as read a bunch of great stuff by people who aren’t me, you can pick up a print copy of The MagPi Issue 36 in your local WH Smith, or download the free PDF from the official website.