This month’s issue of The MagPi Magazine includes another of my tutorials for those looking to get started with the MicroPython platform on the Raspberry Pi Pico microcontroller: a Pico-powered burglar alarm driven by one or more passive infrared sensors.
Originally written as part of Get Started with MicroPython on Raspberry Pi Pico: The Official Guide, my guide to physical computing on Raspberry Pi’s first-ever microcontroller development board, the burglar alarm tutorial builds up step-by-step from introducing a single passive infrared motion sensor to interfacing with multiple sensors, printing status reports over the serial console, and triggering a piezoelectric buzzer in place of a real alarm’s rather louder horn.
As with other tutorials written for the book, full source code – in MicroPython – is provided, along with wiring references designed to make it as easy as possible to add the components to a Raspberry Pi Pico installed on a solderless breadboard. There’s scope for further extension, too: adding break-beam sensors, glass-break sensors, or a code pad for disabling and enabling the alarm on-demand.
As with all projects in the book, the reaction game is designed to build up gradually. The reader is first taken through wiring up a simple circuit with a single LED and a single button, using one to trigger the other. Gradually, the complexity is increased: using the LED to trigger a countdown stopped only when the button is pushed, giving the user a look at how quickly they can react.
The project’s culmination comes with the integration of multiplayer: two buttons are used, and whichever player hits their button first is declared the winner. It’s a simple game, admittedly, but a surprisingly competitive one – and one which introduces a range of core concepts for input handling, timing, and conditional statements.
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.
Today’s launch of the Raspberry Pi Pico, an affordable breadboard-friendly development board accessible enough for education and powerful enough for industrial use, comes alongside the launch of my latest book: Get Started with MicroPython on Raspberry Pi Pico: The Official Raspberry Pi Pico Guide.
Building on my earlier title The Official Raspberry Pi Beginner’s Guide, Get Started with MicroPython on Raspberry Pi Pico offers newcomers to both the Raspberry Pi Pico and the MicroPython programming language an easy way to get started. Building up from an introduction to the board, electronic circuit concepts, MicroPython in general, and MicroPython on the Raspberry Pi Pico specifically, the book walks through a series of physical computing projects – some requiring only the Raspberry Pi Pico, others using low-cost and readily-available additional hardware components.
Each successive project introduces a new concept, from simply lighting an LED and reading a button input to using hardware interrupts, running code on the second CPU core, and making use of the on-board non-volatile flash memory to store logged data. By the end of the book, the reader should know how to use all the most important features of the Raspberry Pi Pico in MicroPython – even if they started knowing nothing about electronics or programming at all.
As always, thanks must be given to those who helped during the production of the book. Particular thanks must go to Ben Everard, who acted as co-editor and also contributed a chapter on using I2C and an appendix on using the programmable input/output (PIO) functionality; Sam Adler, too, returned to provide eye-catching illustrations without which the book would be a considerably duller read.
Also to be thanked are those who provided technical assistance: Alasdair Allan, Aivar Annamaa, Damien George, Gordon Hollingworth, Graham Sanderson, and Andrew Scheller, along with all those who proofed the book ahead of publication. Not forgetting, of course, others at Raspberry Pi Press who work to bring these books to life and to shelves across the world.
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.
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.
Hitting shop shelves just two days before the Raspberry Pi Foundation celebrates its eighth birthday, this month’s MagPi brings a surprise: A permanent reduction in the Raspberry Pi 4 Model B 2GB’s price down to that of the original 1GB entry-level model.
In a three-page feature on the move I investigate exactly what doubling the RAM means for the user, demonstrate how to use the Terminal to see exactly how much RAM your particular Raspberry Pi has available – along with how much is being used by programs and cache, and how much is free or can be freed – and interview Raspberry Pi Trading chief executive Eben Upton on how the price has been brought down, the explosive growth in the Raspberry Pi’s specifications over the past eight years, and exactly how 2GB makes for a great desktop in a world where even entry-level smartphones frequently come with 4GB.
“If you look at Windows, or even a traditional Linux desktop distro, there’s been a sort of relaxation,” Upton told me during our interview for the piece. “As there’s been more memory available, people have loosened their belts a little bit and sort of flumped down and started consuming more memory, when we really haven’t. We’re still using an LXDE-derived desktop environment; you know, we care about every 10MB of memory usage. That’s the reason why the 2GB model is a really, really useful desktop.”
The shift effectively sees the 1GB model retired, though it will still be made available at the original $35 price point for those who have designed precisely that amount of RAM into their projects – but with the 2GB model costing the same, it’s not likely to be selling in any real volume from this point forward.
MagPi Issue 91 is available at all good newsagents and supermarkets now, and can be ordered for global delivery or downloaded as a free Creative Commons-licensed PDF from the official website. The price cut, meanwhile, is live globally today.
My Hobby Tech column this month opens with a look at a surprisingly swish programming environment for the Nintendo Switch, of all things, walks through the creation of a power-saving networked display using the Pimoroni Inky wHAT and a Raspberry Pi, and looks at a book which purports to chart the history of Apple Macintosh gaming.
First, the programming environment. Fuze4 Nintendo Switch, available now on the Nintendo eShop, builds on the Fuze BASIC programming language originally developed for the Raspberry Pi and reviewed – alongside its BBC Micro-inspired housings – in Issue 124 and Issue 136. This time around, though, the language is considerably less BASIC and more like a hybrid between BASIC, Python, and a bit of C thrown in for good measure. It’s also less focused on things like sensor reading and GPIO control – for obvious reason – and instead designed specifically for a single task: making games.
There are aspects that need polish – in particular the sharing of created projects, which at present can only be done via Nintendo’s clunky friends-list system – but overall Fuze4 Nintendo Switch is impressive. You’ll want a keyboard, but once you get started it’s easy to build some impressive projects – one demo supplied with the game showcases a fluid 3D engine with dynamic lighting, created in a remarkably short number of lines.
The Inky wHAT project, meanwhile, was largely a means of documenting something I created for my own use: an electrophoretic display that would display the output of the schedule printer I detailed in Issue 183 without needing to print on physical paper. There’s a twist, too: after finding that the only box-frame available that would fit the project depth-wise was too large, I created a mock-up of an Amiga Workbench desktop to frame the smaller Inky wHAT display – and the effect is surprisingly convincing.
Finally, Richard Moss’ The Secret History of Mac Gaming was a pleasure to read, though a few aspects of Apple’s history are presented from the eyes of a fanboy rather than a historian. Switching between recollection, research, interview content, and contributed material, the book does a great job of documenting the largely-forgotten history of gaming on Apple Macs – though it could have benefited from another editing and layout pass, in particular to avoid the recurring issue where screenshots either appear out-of-order or without any reference in the text.
As always, the latest Custom PC Magazine is available from all good newsagents and supermarkets, or can be ordered for worldwide delivery from Raspberry Pi Press.
Following on from releasing the world’s first magazine with a computer on the cover, for which I provided the launch documentation that made up the historic MagPi Magazine Issue 40, Raspberry Pi Press has done it again: Its new publication, Get Started with Raspberry Pi, once again includes a cover-mounted computer – this time the more powerful Raspberry Pi 3 Model A+ – along with a case and pre-loaded microSD card with adapter.
The book, as its name suggests, is designed for absolute beginners to the Rasbperry Pi – but it’s not a replacement for my Official Raspberry Pi Beginner’s Guide, now in its third edition. Instead, it offers a broader but shallower overview of what the Raspberry Pi can do – starting with setting it up and moving on to both hands-on projects and an overview of community projects and third-party add-on hardware.
Inside Get Started with Raspberry Pi you’ll find a range of contributors’ work, including of course my own: The set-up guide and instructions on using the Raspbian desktop and other software, much taken from the Official Raspberry Pi Beginner’s Guide, bear my hallmark; the book also republishes the Raspberry Pi 3 Model A+ launch feature I wrote for The MagPi Magazine Issue 76, which includes an overview of the device, detailed benchmarking including how it relates to ever other model in the Raspberry Pi range, and an interview with its creators.
Those looking to get the bundled Raspberry Pi 3 Model A+ will need to head to their nearest supermarket, newsagent, or order a copy with free worldwide delivery from the Raspberry Pi Press Store; as with most Raspberry Pi Press publications, Get Started with Raspberry Pi is also available for free download under a Creative Commons licence – though, obviously, the download doesn’t include the cover-mounted computer!