Kategorie: Reviews

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The terrain on Mars is notoriously difficult, so any vehicle intent on exploring the Red
Planet needs to be pretty hardy. Something small and agile, powered by a dependable yet
powerful on-board computer, is likely to fare best against such unforgiving terrain.
Something, perhaps, like a Raspberry Pi. “The rover is inspired by the ExoMars rover Rosalind Franklin and features its most
characteristic design features (drill, solar panels, wheels),” explain ExoMy’s makers
Maximilian Ehrhardt and Miro Voellmy from the ESA’s Planetary Robotics Laboratory. “Its
triple bogie locomotion suspension and six steerable wheels allow for locomotion in very
rough terrain and [also mean it’s able to traverse] obstacles larger than the size of the
wheel.” Better yet, ExoMy can be controlled using a gamepad or a web interface where the
video stream from its on-board Raspberry Pi camera is also displayed. Raspberry Pi 4 Model B is the ExoMy’s main board computer, receiving driving commands
via the web interface. Raspberry Pi “converts them into motor positions and velocity, which
are sent via I2C to the PWM motor board to make the rover move,” reveals Miro.

Small and perfectly formed

Max and Miro chose Raspberry Pi for ExoMy because it “allows the use of a full-fledged
operating system and provides a wide variety of GPIO pins and a great camera interface.”
They were also attracted by its low cost, worldwide availability – important given their
ambition to make space robotics more accessible – and the large community surrounding
it. “ROS (Robot Operating System) support meant we could use a lot of available open-
source software and ensure that ExoMy stays very modular,” says Miro. Both engineers had used Raspberry Pi in projects before. Miro used Raspberry Pi to
control a spherical robot at the Automation and Robotics Laboratory at ESA that floats on
air and which simulates satellites and spacecraft control algorithms.
Max, meanwhile, worked on a sounding rocket project at university for which he created a
Raspberry Pi telemetry logging HAT.

Building blocks

Although other open-source rovers exist (notably Sawppy and JPL), these had customised
metal housings and are far more expensive than the $250 to $500 required to build your
own ExoMy. A well-received prototype had been produced by trainees in 2018, but it was
rather costly and had reliability issues. At the start of 2020, Miro and Max set out to design
a reliable and reproducible version that was also far more affordable. They designed all
the mechanical parts at the Planetary Robotics Laboratory and 3D-printed them, which
took approximately two weeks. Assembly required another two days. The electronics and
screws all came from commercial suppliers. “The idea was that everyone interested in building ExoMy can easily order, install, and use
it. They can even use the same software tools as in the Planetary Robotics Laboratory,”
says Max. “We try to use as much open-source software as possible,” adds Miro. “ExoMy
is, however, designed in SolidWorks, which is unfortunately not free.”
Details of both the hardware and the freely available software used can be found here.

Max and Miro encourage others to give it a try and advocate using Docker, since it
reduces the need to repeat installations and “allows for a repeatable and reliable software
environment”. Discussing your design challenges with someone, getting a second opinion,
and inviting different views of a problem generally leads to the best solutions, they advise.
You can find out more about ExoMy by joining on Discord.

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The special red-foil cover is in Raspberry Pi colours (red and white) and unfolds to reveal all 100 covers of The MagPi magazine. Inside the special edition is a 20-page feature celebrating 100 moments from Raspberry Pi history.

Discover 100 Raspberry Pi moments

We’ve scoured the previous editions, talked to all the community, and all reminisced over eight years of Raspberry Pi. The results is 100 greatest Raspberry Pi moments, achievements, and events from 100 editions of The MagPi magazine.

Make Santa’s Run with recycled bottles

Mike Cook serves up a double-whammy for Christmas with a game that has you delivering all 100 editions of The MagPi. Santa’s Run uses recycled plastic bottles as controllers. 

ExoMy Mars Rover and other amazing projects

We’ve gone all out this month with some of the best community projects ever to feature in The MagPi magazine. Like ExoMy, the low-cost Mars Rover designed to be 3D printed at home. 

Build a handheld console

KG uses two of the latest handheld gaming kits to explore portable console gaming with Raspberry Pi. Combine the small size of Raspberry Pi Zero with battery power and a small screen to game-on-the-go.

Say hello to Raspberry Pi 400

Raspberry Pi’s all-in-one desktop computer combines the power of Raspberry Pi 4 with the official keyboard. Repositioning all the ports to the back, we feel it’s Raspberry Pi perfection. Our feature benchmarks, tests, and gets inside the latest Raspberry Pi.

Argon One M.2 review

Super-charge Raspberry Pi with a super-fast M.2 SATA SSD drive for vastly improved storage performance. We are impressed with the latest Argon ONE M.2 case, which delivers on multiple fronts.

10 amazing festive projects

Light up the holiday period with our guide to festive illuminations, decorations, and ornamentations. It’s the perfect way to weave digital making into your festive break.

Learn Raspberry Pi OS

Newcomers will find our guide to Raspberry Pi OS (the operating system at the heart of Raspberry Pi) invaluable. But even experienced makers will find something to learn from this collection of incredible Debian and Raspberry Pi OS guides.

Pick up your copy of The MagPi magazine#100

The MagPi magazine is available as a free digital download, or you can purchase a print edition from our Raspberry Pi Press store.

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Save 37% off the cover price with a subscription to The MagPi magazine. Try three issues for just £5, then pay £25 every six issues. You’ll save money and get a regular supply of in-depth reviews, features, guides and other PC enthusiast goodness delivered directly to your door every month.

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We’ve put together a selection of fantastic community projects to give you some inspiration
for decorating your house inside and out. Let’s get festive.

Outdoor decorations

Light up your street with pure seasonal cheer (and some LEDs)

Xmas lights for beginners

Sometimes you need to do something a little grand, especially for the holidays,
and lighting up the outside of your house is certainly one excellent way to do it. If you’re
not sure where to begin with this, then this guide by Makin’Things will not only get you set
up with lights, but also how to get them to sync up with music. It uses the excellent lightshowpi Python library (lightshowpi.org) to make the music
syncing fairly easy. It also uses relays and a lot of power, so be extra careful if you plan to
follow it! magpi.cc/xmaslightsbeginners

2018 Christmas Light Show

Are you really doing your outside lights correctly if you’re not worrying your
neighbours? If you really want to see how much you can do with lightshowpi and the kind
of setup Makin’Things does, this light show which includes lawn ornaments, a tree, and
4000 lights should give you some inspiration. It’s all still controlled by music as well. Once again, you’ll need to be extremely careful with
heights and electricity use if you plan to recreate this. magpi.cc/2018lightshow

LED display matrix

If you don’t fancy doing the whole house, then maybe a window will do! Andrew
Oakley shows you through how to create a set of animated LEDs for not too much money.
It also takes PNG images, so you don’t need to program each individual LED and it can
even scroll text as well! While relatively simple and cheap, you may have to do some woodwork, so get it started
ahead of time and make sure to be careful when using any carpentry tools. magpi.cc/ledmatrix

Power up your tree

Even with just a fake Christmas tree, you can really bring it to life with a
Raspberry Pi

Smart Christmas tree lights

Not only are these Christmas lights made with fully programmable NeoPixels,
giving you unlimited flexibility in colours and patterns, but they also add voice control so
you don’t even need to touch them! Sure, you could implement some remote SSH system,
but this way is a bit more fun. We made this in The MagPi last year and we think it still holds up! You may want to invest
in a little 5V power supply adapter as changing out batteries all the time does get a little
boring. magpi.cc/smartxmaslights

Tree Star

Another The MagPi original, this one uses a 3D-printed star to act as a tree
topper, with some LEDs installed inside to light it up! It’s been a few years since we
selected this specific 3D star file from Thingiverse, so you might be able to find something
better or whip one up yourself.

Make sure to scale the star for your tree, though – behind the scenes, this star wouldn’t
stay on the original tree we had and we needed a bigger one! If you’re doing the smart tree
lights as well, you can easily combine the two. magpi.cc/64

YouTube Christmas Ornament

We all know someone who needs to see the Coca-Cola Christmas advert
before Christmas starts for them. You may even be that person! Relive all your favourite
Christmas adverts through this ingenious build that puts a tiny display on your tree to play
them all. You have to supply the videos yourself, though, so if you really want to embarrass
someone, you’ll need to digitise some old VHS tapes of Christmas past and upload them.
Or just put your favourite Christmas films on there. magpi.cc/xmasornament

Deck the halls

Give the rest of your home a bit of seasonal magic

Christmas house and snowman

This little diorama was created by Stewart Watkiss (aka PenguinTutor) to be
part of an outdoor railway. However, it also functions as an indoor decoration. A string of
LEDs on the front of the building act as some nice Christmas lights, and a snowman has
NeoPixels inside so it can glow with awesome Christmas power. The house and snowman were 3D-printed, although you could probably find some model
kits that will allow you to do similar. We like the snow effect on the tray, and the little tree
and people to give it the correct sense of scale. magpi.cc/xmashouse

pireplace

We must admit, we don’t /quite/ get the appeal of the fake fire on the TV during
Christmas. This we can get behind, though – creating a fake fireplace and adding
NeoPixels to create a warming fire effect that is sure to cozy up any room. It’s even got a web interface you can control from your phone, allowing you to change the
colours and turn it on and off. Very handy, and maybe a little spooky if you time it right to
catch folks in the act of present-feeling. magpi.cc/pireplace

Smart gingerbread house

Gingerbread houses are a classic Christmas ornament for some families – one
that probably wouldn’t last to Christmas Day intact in our house. Estefannie decided to
take it about two steps further, as she’s wont to do, and fully automated a smart
gingerbread house. It’s also covered in enough sweets to attract Hansel and Gretel.
The whole thing also has a remote control function so you can switch the lights on and off,
open and close the door, and a lot, lot more. magpi.cc/gingerbread

Sense HAT advent calendar

Too impatient to wait until Christmas Day for your presents? Then how about a
slow drip-feed of daily gifts like you’d get in an advent calendar? This digital version
doesn’t give you chocolates, unfortunately, but it is a neat and simple little project to help
you get into the festive mood. It’s from the Raspberry Pi Projects website, so it’s nice and easy to set up and requires
very few components as well, relying more on code than anything else. magpi.cc/senseadvent

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Nevertheless, many have concerns about subscription costs and privacy of the data
collected. The good news is that many open-source Raspberry Pi automation systems
have matured significantly over the past few years. They now challenge the big players,
are free of charge, and put your privacy first. Over the next three issues we’re going to set
up a smart home from scratch.

Step 01: Your new Home Assistant

To make our home a more fun place to be, we’re going to set up a home automation
system. This is software that can communicate with multiple devices and make changes to
your environment based on a rule set. Sounds a bit complicated, but the ‘HA’ scene has
got a lot friendly over the past few years. We’ve chosen the appropriately named ‘Home
Assistant’ (home-assistant.io) because it is a complete operating system package and
runs well on Raspberry Pi 3 or above. Best of all, it has incredible support for hundreds of
smart devices.

Step 02: Installation and first boot

Home Assistant is available as a full microSD card image – no operating system installation is required in advance. To get the image, go to magpi.cc/homeassistantio. Make sure you pick the right one because different images are available for Raspberry Pi
3 and 4. Once downloaded, burn the images to a microSD card using Raspberry Pi Imager
(magpi.cc/imager). We strongly recommend using a wired Ethernet connection for
reliability. Whichever you choose, use a wired connection when booting up for the first
time. Be patient, Home Assistant will take up to 20 minutes to start up on first boot.

Step 03: Terminology

Before going any further, it’s useful to understand the terms used in Home Assistant.
Take a look at the ‘Home Assistant terms’ box and understand Integrations, Devices,
Entities, and Areas. Take some time to become familiar with the terms while Home Assistant is setting up.

Step 04: First connection

After 20 minutes (don’t worry, it’s a one-time thing), you should be able to see a welcome
screen. Open a web browser and visit: http://homeassistant.local:8123/. If not, try using a network utility like Fing for iOS or Android to locate the IP address of the
server and try that instead. If you still can’t get a connection, try waiting a little longer.
Eventually, you should see a ‘Preparing Home Assistant’ screen. This will shortly change
to an account creation screen. Home Assistant has full support for multiple accounts with different permission levels. The
account you create here will have full control over the system.

Step 05: Initial settings

Once you’ve completed the form and created your first account, you will be asked to select
your location and give it a name. This information never leaves your network and is used
to get information on sunrise and sunset times for where you are. You can also choose
your preferred unit of measurement. These details can be changed at any time. You’ll now be taken to the Overview dashboard, the heart of the system. A dashboard is a collection of panels that display various bits of information and allow you to control your environment. Your system is already up and running.

Step 06: Your first dashboard

The Overview dashboard has been populated with some initial panels. Largest is the
weather panel, based on your location. You will also see ‘badges’ at the top. Try clicking

on the Sun badge for data about today’s sunrise and sunset. There will also be a person
badge which will probably say UNK for ‘unknown’. We’ll come to that later. For now,
explore the left-hand menu. You can see a map (this will get more useful), a log of all
events, and several configuration options. You’ll also see Notifications – the chances are,
you’ll have one waiting. If you do, Home Assistant has discovered things on your network
that it can talk to.

Step 07: Your first integration

Did you click that notification in Step 5? If so, you’ve probably been informed that Home
Assistant has already found some devices on your network. It can be surprising how chatty
some things can be. Printers, routers, and media systems such as Sonos will all happily
introduce themselves to Home Assistant. To actually start using the integrations, click on Configuration then Integrations. Now click Configure on your choice of integration. Some additional information may be required, but often auto-discovered integrations work out-of-the-box. If a particular integration is not of interest to you, click Ignore to hide it.

Step 08: Automatic dashboards

Once you’ve enabled and configured some integrations, go back and have a look at the
Overview dashboard. Home Assistant will have automatically added an appropriate panel
to show data or add controls. If you have a Philips Hue or Ikea Trådfri gateway, your lights
will have been discovered and added to the panel. This feature makes getting started with Home Assistant a breeze. If you’re happy with this, you can let Home Assistant update and configure your panel as you add new integrations and devices. However, if you want full control, you can disable this feature and create your own panels.

Step 09: Your own dashboard

When we installed our Home Assistant, it found our networked printer and created a panel
that showed the ink levels for each cartridge. It’s a bit dull, so let’s make a better one. By
clicking on the three dots at the top-right of the screen, we can Configure the UI. You’ll see
a warning that automatic configuration will be disabled. You can now edit, move, delete,
and add new panels. You can also add tabs across the top and you can have as many
dashboards as you like. We created a new tab for our printer.

Step 10: Adding panels

We now have a nice, clean area to work with. Click the + icon at the bottom-right to add new panels. You will see all the default panels available, covering many different use
cases. These include switches, gauges, playback control for media centres, and many
more. You can even design your own. We clicked the ‘gauge’ panel as that seemed best
for printer ink. Home Assistant is helpful enough to work out what entities are best for the
type of panel and you can control certain aspects such as warning thresholds. We added a
gauge for each of our printer ink cartridges.

Step 11: Adding new integration

We strongly recommend spending some time looking at the available integrations. Click on
Configuration, Integrations, then click the + icon. You will be presented with a bewildering
list of possibilities. We found an integration for pi-hole, the ad-blocking service. After
entering the address of our Raspberry Pi 4 running the service, we had a panel full of stats
to look at. Some integrations increase the capability of Home Assistant to talk to other
devices. For example, the MQTT (Message Queuing Telemetry Transport) integration
allows Home Assistant to subscribe to MQTT topics and trigger events. If you’re handy
with Python, you can create your own custom integrations too.

Step 12: Going mobile

If you’ve set up all your lights to work with Home Assistant, it’s going to be a bit pointless if
you have to run to a computer every time to need to flick a virtual switch. An essential part
of any Home Assistant setup is the smartphone app (iOS or Android). This not only allows
you quick access to your dashboards, but also adds you as an entity.

The app communicates with Home Assistant and provides location and activity information. All your health stats tracked by your phone can be added and your location reported. All this data stays in your network and you can switch it off any time, but there are great possibilities that we’ll look at next month.

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Astro Pi resources

This versatile board was designed especially for a space mission. Two Astro Pi units
– comprising a Raspberry Pi with Sense HAT in a special case – are currently
aboard the International Space Station (ISS), orbiting 408km above the Earth. Astro Pi is an ESA (European Space Agency) project run with the Raspberry Pi
Foundation. It enables young people to conduct scientific investigations in space by
writing computer programs that run on the Astro Pi devices aboard the ISS. Students
up to 19 years old can take part in the Mission Space Lab, while those 14 and under
can get involved in the simpler Mission Zero. Even if you don’t want to take part, Astro Pi has a solid set of resources designed to
help students set up the Sense HAT and collect data from it.

Experiment with the Sense HAT

While no longer available in print form, this compact book from The MagPi Essentials
range can still be downloaded as a free PDF. An extensive feature on the Astro Pi
mission details how the units were designed and then launched into space to reach
their new home on the International Space Station – to be joined by British ESA
astronaut Tim Peake soon after.

The book then launches into some step-by-step tutorials to help you get started with
your Sense HAT, demonstrating how to display images on the LED matrix and how
to read the various sensors on board, including the gyroscope, accelerometer, and
magnetometer. Fun projects to code include a Gravity Simulator, Digital Magic 8 Ball,
Interactive Pixel Pet, Astronaut Reaction Times Game, and Data Logger.

Raspberry Pi Projects

The Raspberry Pi Foundation’s learning resources website features several tutorials
to help you get started with your Sense HAT and make some fun projects with it
using Scratch or Python. Even if you don’t own a Sense HAT yet, you can
experiment with writing Python programs in an online emulator to see the effects.
Start with a simple Countdown Timer on the board’s LED matrix, before moving on to
games such as Flappy Astronaut, Marble Maze, Tightrope, and Pong. More complex projects include an MP3 Music Player and Weather Logger. There's
even a tutorial to explore SpaceCRAFT – a winning Astro Pi competition project – in which you can visualise data from the Sense HAT’s sensors in the Minecraft world.

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Step 1: All USB devices are not the same

Many people tend to think you can plug any USB device into any other, but this is not strictly true. The sort of USB connector on a Raspberry Pi computer is USB-A. This connector is always used by a USB host device, like a computer. A host device supplies power and is in control of the process of communicating with the other sort of device, a USB client device. If a client wants to pass information to a host, it has to wait until it is asked by the host if it has anything to say.

Step 2
: Interconnectivity

You can’t plug a host into a host, nor can you plug a client into a client. Quite simply, the connectors on the USB cable will stop you doing this – even if you make up a special cable. it simply would not work. So while it is fine for a Raspberry Pi computer to connect with a MIDI sound module, you can’t connect it to a DAW (digital audio workstation) like Reaper or Ableton running on an other Raspberry Pi computer or other laptop. This limits the role your Raspberry Pi computer can play in a MIDI system.

Step 3
: Solving the problem

You could use a MIDI interface cable on both computers and connect the MIDI sockets up with a couple of MIDI leads, but we have found this seldom works because of the accuracy of the baud rate produced by these interface leads. So, we have come up with a solution to get round this by enlisting the help of an Arduino, like we have done in the past. But this time we will be using a different sort of Arduino, the Pro Micro, based on the ATmega32U4 chip. We get the bonus of using the Arduino’s peripherals as well.

Step 4
: How does this work?

The idea is that the Arduino presents a USB MIDI client interface to a host and the we can communicate with it from the Raspberry Pi computer using its serial port. This can be at a fast rate, and we are not faced with the problem of trying to get the serial port to use MIDI speeds, which are not directly supported. The block diagram of this project is shown in Figure 1. While we could wire the Arduino to the same cable as our Tap-An-LED box, we did not want two boxes permanently joined together with a common flying lead.

Step 5
: Making the GPIO connector extension board

To get round this, we made a little 12-pin GPIO extender board so that we could use the two boxes together. This is simply a piece of stripboard 16 hole by 6 strips – Figure 2 shows the track cuts on the underside. To the copper side, solder a 12-pin 2-row surface-mount socket; to the front, solder two 12-pin 2-row header pins. Figure 3 shows this, along with the way in which it is wired up. To save it looking too messy, the two stages of the wiring are shown separately, and a photograph of the finished item is shown in Figure 4.

Step 6
: The Arduino board

There are two types of Pro Micro Arduino: one with a mini USB connector, and one with a micro USB connector. We prefer the mini connector, as it tends to be more solidly attached to the board. It is slightly wider than the one with the micro connector, but either would fit on the stripboard shown in Figure 5. On the reverse, each strip row is broken in the middle to prevent the board from shorting out. The board has straight header pins soldered to it and there is a matching socket soldered to the stripboard.

Step 7
: Powering the Arduino

The link on the top corner of the Pro Micro is left open. This means the board runs at 3V3 (3.3V) and is only powered when it is plugged into a USB host. To stop the Raspberry Pi damaging the board with a serial signal when the Arduino is unpowered, a 3K3 (3.3kΩ) series resistor is inserted in Raspberry Pi’s TX signal line. On the front panel is a 20-pin 2-row socket to access the peripherals of the Arduino. For clarity, the diagram shows this connector as being split into top and bottom halves, but it is just one socket.

Step 8
: The box

We made the box using our normal method of 30mm pillars holding the top and bottom apart, with the sides glued together as a ring. The TX and RX LEDs on the Arduino are useful in seeing if MIDI messages being sent, and received. So that we could see the LEDs blink, we used two 13mm long, 6mm diameter, clear acrylic rods glued in the top to act as light pipes,. A message is being passed when the LEDs are off. Figure 6 shows the assembled box. The layout drawing for this box, and more construction photographs, can be found on our GitHub site (magpi.cc/pibakery).

Step 9
: Bonus I/O

As we had an Arduino, with all its peripheral goodies doing nothing, we brought them out to a 20-way socket on the box lid. The pinout of this is shown in Figure 7. We have access to 16 different pins and over half of them are dual function. For example, we can use pin 13 of this connector as a PWM-capable digital pin 6, or as analogue input A7. You can only choose one of these two functions to use at any one time. The API for communicating with these peripherals is shown in Figure 8.

Step 10
: The Arduino software

The Arduino software uses the MIDIUSB library, to present itself as a MIDI HID (human interface device) client device when plugged into a host. This communicates with the host by using four numbers to define a MIDI message; we call this a ‘frame’. These frames can be transferred to and from the host by the Arduino and also passed to and from Raspberry Pi. The Python software then uses these frames to deal with messages sent to it, or generate messages to send to the host or communicate with the Arduino peripherals.

Step 11: Applications

We have written several applications to demonstrate the capability, and workings, of our client interface, both with and without using the Tap-An-LED interface. Many of these look a lot better as a movie, rather than a still. For example, we have four midi_note_display programs. These take a stream of MIDI note messages, sent by the host, while playing a MIDI file – and LEDs or Raspberry Pi’s screen change accordingly. The colours used are changed according to the velocity of the note. LEDs and the screen can display keyboards, or a unique LED for each note – see Figure 9 for one example.

Step 12
: More applications

There is xy_pad.py, an example of using the raw data from the touch sensor screen to control two parameters as an X-Y pad in Ableton. In addition, midi_duet.py fires random notes, in the key of C, into Ableton for you to play along and improvise against. Then there is peripheral_request.py for getting and setting data from the Arduino’s peripheral pins. To go along with all this, we have all the Ableton Live sets you need to work along with these examples. Many musical interfaces you can buy come with a licence for a cut-down version of Ableton Live.

Step 13
: Other DAWs

There are many more DAWs (digital audio workstations) other than Ableton. There are top-end applications like Apple’s Logic Pro X or FL studio, as well as free ones like the Windows-only Cakewalk, or the Apple-only Garage Band. Also, there are budget DAWs; perhaps one of the best of these is Reaper. Garage Band has very good-quality sounds, but the big problem we see with it is that the MIDI works for only one instrument and the implementation of MIDI controls is limited. There are many more DAWs if you search for ‘Free DAW’.

Make sure you catch up with Part 1 of this Tap-an-LED series in issue #97 of The MagPi Magazine, and Part 2 in issue #98.

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The Lyra Handheld Game Console (£229 / $300) is attempting to change that. After a successful launch in July 2019, Kickstarter veteran Creoqode set out to make a handheld
gaming system that looked the part, was easy to assemble, and was more powerful
than any other Raspberry Pi-powered handheld game console on the market at the
time. The result is Lyra, a handheld game console that is available in kit form (or fully
assembled if you fear nuts and bolts) and utilises the power of Raspberry Pi
Computer Module 3 Lite. Unlike many other Raspberry Pi-based handheld game consoles available today, the
Lyra resembles the form factor of a Sony PSP and Nintendo’s Game Boy Advance,
which makes a nice change to the tried-and-tested Game Boy-style systems, along
with the bonus of a larger, widescreen display.

Easy assembly

When the Lyra arrived, we were impressed with the packaging, which can double up
as a protective case when your Lyra is not in use, and the quality of the parts in the
kit – we loved having the option of clear or black buttons to choose from.

As we are partial to a bit of tinkering, we opted for the kit version, so we had to assemble our Lyra ourselves. Whilst there were no physical instructions provided, the online
tutorial is packed with detailed photos and step-by-step instructions and we had our
Lyra assembled in under 15 minutes. The fiddliest part was attaching the screen when closing the case! For convenience, Creoqode has created a custom-built image that utilises RetroPie, so once this was downloaded and flashed to our microSD card, we were up and running in no time. It’s a shame that a manual install guide was not available for those who prefer setting up RetroPie to work on the Lyra themselves, especially as pre-build SD card images can quickly become outdated.

Small but mighty

One thing we liked about the Lyra was the inclusion of the Raspberry Pi Compute
Module 3 Lite (CM3L). Whilst pricier than a Raspberry Pi Zero, the CM3L brings the
power and small footprint that is perfect for a handheld game console.

The CM3L clips into Creoqode’s custom-made circuit board and whilst the lack of WiFi is a
shame, the micro-USB port allows you to connect your own USB devices (with the
help of an adapter) for Internet connectivity. The addition of an HDMI port allows you
to connect your Lyra directly to a large display / TV, which is great for gaming at
home too. We did notice that the case didn’t quite close perfectly, so small gaps were visible by
the micro-USB charging and headphone ports, and the lack of a screen protector
was a shame, but the performance of the Lyra is second to none in a competitive
market for handheld gaming.

Verdict

8/10 The Lyra is a great product in a competitive market. Assembly was straight forward
and the power the CM3L brings is fab. The case could be better, but for gaming on
the go, it is ideal.

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While she’s always been a part of the streams, more recent ones have been taking place much later in the day UK time so that they’re more accessible to American students. “We’re having a lot of fun!” Christina tells us. “It’s honestly the highlight of my week, and
we’re getting a positive response from the community. It’s really been nice to connect with
professionals and youth creators and share their experiences with the community. I’m
excited to see where the live stream adventure takes us!”

How did you first learn about Raspberry Pi and related programmes?

Honestly, I learned about Raspberry Pi when I found the job listing in November 2017. I
was in a temporary admin role supporting school while the principal was on parental leave,
and I needed a job! I knew about Arduino because my dad made projects, and I knew
about coding and Scratch because I was a teacher, but I had never heard of Raspberry Pi
before. Even during the interview process, the focus was on our clubs’ programmes in the
USA. Then when I got the job (YAY!) and was meeting all the teams, I truly started to grasp
the global reach of both the hardware and our education programs.

To be honest, I had friends who were familiar with Raspberry Pi and were confused by
why/how Raspberry Pi had hired me, a former teacher and not an experienced hardware
or software engineer. I also had friends who thought I made a career change and was
working at a bakery. I share the above because I want folks who are reading this to know
that they can and should apply to jobs that interest them. I got this job because I am an educator, I love kids, and I’m good at community engagement. If I had listened to one group of friends, I might have felt I wasn’t qualified to work at RPF or if I listened to another group, I might have thought that working at a place named after a fruit would be a poor career decision. Applying to this job was one of the best decisions I ever made.

How did the current Digital Making at Home streams come about?

Digital Making at Home was (and still is!) our response to supporting young people and
families staying at home this year. In March, we put together a small (virtual) team to think
creatively about what we could do to support the community at this time while we are also
staying home. We started with recorded code along videos and got feedback that folks
wanted to interact with us live, so we created the live stream, and I absolutely love how it’s
evolved to include conversations and coding with people from all over the world!

What other stuff have you done with the Foundation?

Being on the North America team, we’re such a small team that we all do a lot to realise
the Foundation’s mission. So I’ve done a lot: events, clubs, Picademy, online courses! It’s
amazing!

Any upcoming plans you can share?

I’m really excited about the work we are doing to prepare for Coolest Projects 2021! Stay tuned for how you can get involved!

Reading Time: 3 minutes

This is the first time we’ve seen a product that uses a Raspberry Pi for a tracking telescope before – or more accurately, an observation station. See, Stellina (£3,643 / $4,700) isn’t just for getting a better look at the moon or maybe seeing a planet, it’s designed to look into the deep reaches of space and bring you images of nebula and galaxies that you could never see with the naked eye. And it’s all controlled from a smartphone or tablet, which is pretty clever.

Space in your hands

Probably the most unique feature of Stellina is how it’s not only fully controlled from
your phone or tablet, but also you get to see what it’s pointing at from your device.
No need to peer through a viewfinder if that isn’t your thing, although if it is your thing
you may want to look somewhere else.

A Raspberry Pi 3 inside creates a local wireless network that works with a Stellina app for remote viewing and controlling. Because of this control, pointing at an object is incredibly simple: there’s a predetermined list of cosmic destinations you can select from in the app, and Stellina automatically swivels and raises its lens towards it before continuing to track it throughout the night if you so wish. The longer you look at these objects, the better picture you’ll get as the software ‘stacks’ the photos on top of each other to get a
clearer image. You can then do some colour correcting of the image when saving it,
or even just invert the colours for that very scientific black-on-white look.

Chasing Saturn

We took a Stellina out to a field in the middle of nowhere one evening to give it a proper test and we were pleasantly surprised by the results. Despite having the various planets in our solar system selectable to observe, the real magic occurs when you get it to look at nebula and galaxies. As you might expect, the darker it is the better, and some patience is required if you want to get some truly astonishing sights. Saturn was the first and last target of the evening, with barely a blurry smudge visible just after dusk, and the rings clearly circling it several hours later. Which was quite breathtaking, even if the whirring of the motors as it tracked the
planet across the sky was a touch distracting. We feel like that this device is more aimed at folks with a balcony who’d rather be sitting inside while looking at Jupiter or Andromeda – it does claim to filter out light pollution after all. The kind of people who might have a nice balcony to put it on may also be a bit more comfortable with the hefty price tag, which runs quite a lot higher than more traditional telescope/automated tripod systems. The magic here is in the software and ease of use then, although you will be paying a premium for it – however, a much cheaper version is in the works and we’re interested to see how it compares.

Verdict

9/10 While the price is eye-watering, if you really like looking at stuff in space and don’t
get out of the city much, you could have a magical time with it.

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“The convergence of the two ideas was what motivated me to build it,”
he explains. “I also liked the ‘Americana’ influence captured by the use of the Weber grill.
Weber is an icon of the American backyard BBQ culture; I like that it can continue to serve
up food for us humans to enjoy.“

Horticultural haven

Armed with his elderly BBQ and a Raspberry Pi-based Smart Garden System Kit (SGS v1)
from SwitchDoc Labs, Etienne set to work to inject new life into the old grill. He needed to
make modifications to both the Smart Garden System Kit and the BBQ – for example, the
Smart Garden Kit was designed for indoor use, so Etienne needed to ‘weatherise’ it, and
the BBQ had to be transformed into a planter box with an adequate drainage system,
which required some carpentry and plumbing skills to be called into action. This didn’t hold
Etienne back, however: “I found a tutorial video on building planter boxes and applied
some of the knowledge that I learned watching it. I have built significantly more complex
carpentry projects than this one in the past.”

Once his planter was ready to propagate, the technical side came into play. “The Smart
Garden works essentially in an ‘event-based’ model,” he says. “It uses a module in Python
called APScheduler to create recurring events. For example, it will ‘check’ the soil moisture
sensor level every 15 minutes. If the return of this ‘check’ is below a predetermined
moisture threshold, then an ‘alarm’ is created to water the plant.” The tank capacity is also
monitored by an ultrasonic sensor which again triggers an alarm when the water level gets
too low. However, the other sensors – including air quality, sunlight, and temperature – are
for information purposes only, so no alarms are required.

Etienne did some tweaking to the Python code to fit his specific needs in the extreme Las
Vegas environment – for example, he changed the soil moisture check to every five
minutes instead of 15, so that plants wouldn’t have to wait too long to be watered, and he
changed the length of watering time so that they got enough water. He also tells us that he
“used a longer ‘dumb’ moisture sensor to measure deeper into the soil than the moisture
sensors of the Smart Garden can reach. The soil moisture at seven inches deep was not
high enough.”

Feeling hot, hot, hot…

So, what’s Etienne growing and how are the plants faring? Having originally planted
tomatoes and peppers a little too late, he soon found that the Las Vegas summer desert
temperatures proved too much for his young vegetables and they succumbed to the
extreme heat (up to 46°C!)

That said, he’s now feeling more confident: “Now that the heat
of the summer is passed, I have planted again for the fall season. I am growing mini yellow
squash, mini cucumbers, and a poblano pepper plant. I am not late planting this time
around so I am optimistic that the result will be good.”

Feedback from family and friends has been very positive, and it has educational benefits
too. “They also appreciate that I do these projects, not only because I enjoy them, but to
expose my son to STEAM educational opportunities,” explains Etienne. “I can clearly see
the evolution of his questions over time, reflecting his increasing understanding.” He adds,
“A mixed vegetable grilled antipasto is delicious eating for a BBQ; this Weber won’t be
cooking it, but it might provide some of the ingredients!” It’s an excellent and pleasurable project where you should (extreme temperatures
permitting!) have something to show for your labours at the end – why not try it
yourselves?

Reading Time: 3 minutes

He eventually chose one celebrating a different game, kicking off his Raspberry Pi-based Lunchbox Arcade Game project.

“I used to have a cool metal Pac-Man lunch box for school but trying to get a Pac-Man one is nearly impossible, and ones that do come up go for silly money on eBay,” he explains. At more than £60 a tin, he couldn’t bring himself to drill holes in an original 1980s version. Instead, Rich decided to modify a Gauntlet one.

Most of the parts for what became a roughly £250 build came from Arcade World.

Lunch bunch

Rich had already built three Windows-based arcade machines having moved on from assembling his own PCs, plus one using Raspberry Pi. For his Lunchbox Arcades, Raspberry Pi was a shoo-in. 

“So much power in such a small form factor makes Raspberry Pi a great choice for mini arcade machines,” says Rich. “With all my machines the sound quality is important, so I’ve fitted the largest speakers the lunchbox could realistically support.” He strengthened the tin all round using plywood in the base and fitted new rivets into the metal sides. 

Next came the lid. He removed the original hinge, realising it wasn’t strong enough to support the LCD screen. “I was able to gain some height with new hinges. This allows the screen to fold inside the casing, giving a seamless look when shut,” Rich says. “The joystick is removable to allow the lid to close. It’s a modified Sanwa joystick shaft with a quick release system. The sprung release shaft comes off easily and can be stored in the back of the machine. The original latch holds the lid shut.”

It wasn’t all straightforward, though. “Airflow was also important, so a 60mm fan forces air inside over Raspberry Pi and out of two slots cut in the control panel.” With hindsight, says Rich, this could have gone on the rear rather than where the handle is. A Gauntlet fan grille he created on a 3D printer now covers it up a bit.

Power play 

The Lunchbox Arcade runs off a 12V, 6A power supply. A buck voltage reducer takes this down to 5V for Raspberry Pi and the screen. “The buck voltage PCB will also look after a rechargeable battery, so I’m trying to source a 12V battery that will fit in the case and also provide a good few hours playtime,” says Rich.

Although the project has the potential to be self-powered, he didn’t want to compromise on the speakers. “The speakers and amp were the whole reason behind the 12 volt power supply. I didn’t want some tiny speakers and a 5V amp.” Despite having to reposition the heatsink to accommodate the amp, the audio setup proved worth the extra hassle. “The speakers sound really good as they resonate through the tin and have good bass, which surprised me,” says Rich. 

He thinks others might enjoy making something similar. Raspberry Pi is perfect for this size of machine. It has plenty of power, great visuals, and no slow-down in the games,” he enthuses. If you’re embarking on your own arcade project he advises, “Always think about maintenance and how you’re going to access all the components in the future. The controls need to be easy to remove, so making up some sort of quick wiring connect that you can just unplug will save a lot of hassle in the future.”

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This month, we’ll add a disc drive to Raspberry Pi 4, connect a TV to make the most of CRT-era graphics, and overclock Raspberry Pi for an emulation performance boost.

We’ll use this hardware to add disc support to the system we made in our DOS emulation tutorial and to emulate early disc-based consoles. We’ll also explore the best legal landscape of disc emulation.

This project works best with Raspberry Pi 4 and a freshly installed Raspberry Pi OS (32-bit).

Images, discs, and the law

In the UK, you’re not allowed to make copies of software, video, or music discs you’ve bought (here’s the law); there are no exceptions for backups or transcoding to play on another platform.

Unlike some PC software, permission to make copies for personal use is never granted in console games’ End User License Agreements (EULAs). You have to use the original discs.

More obviously, you can’t download disc images that someone else has made (even if you already own the game) or console operating system BIOS files. This means we’ll be restricting ourselves to emulators that can actually play games from disc and which have a High Level Emulation (HLE) BIOS.

This peculiar combination of laws currently rules out a number of normally viable emulation platforms, such as the Amiga CD32, for which BIOS images are legally available via Cloanto’s Amiga Forever, as the emulators that use them expect you to work with CD ISOs rather than original discs.

Similarly, although the RetroArch Disc Project is doing fine work on introducing disc support to certain Mega CD, Saturn and 3DO emulators, most of the emulators that currently have real disc support require BIOS images that you won’t be able to legally obtain in the UK.

Read on, though, because that still leaves a few disc-based gaming platforms you can bring back to life with Raspberry Pi.

Disc support

USB disc drives and Raspberry Pi can be an awkward combination. Modern bus-powered drives often use dual power/data USB connections that require more power than Raspberry Pi can readily supply, and don’t play nicely with USB hubs or external 5V power adapters.

Emulation adds to these problems, as early consoles often expected the disc to be spinning at all times, which many portable USB disc readers are unhappy with. Similarly, avoid Blu-ray drives: their spin and spin-down speeds frequently don’t mesh well with the expectations of emulated consoles.

A standard internal DVD-ROM drive is perfect: this build used a 2008 Sony NEC Optiarc AD-7203S SATA DVD-RW. Drives in this range are widely available for around £15, and this project is an excellent use for any old PC CD or DVD drives you might have lying around.

To connect it, you’ll need either an external disc drive enclosure or SATA to USB adapter that takes external mains power. The kit photo above shows a StarTech USB2SATAIDE, which also supports IDE CD-ROM drives and hard disks. While this adapter is a little pricey at £42, similar hardware can be bought for about £20.

01 Connect your disc drive

Plug the SATA data and power connectors of your adapter into the back of your DVD-ROM drive, plug the adapter’s USB connector into Raspberry Pi, and its mains adapter into a plug socket or power strip.

This also works with externally powered drive boxes, which look better if you want a tidy and portable final product, but will require a little more assembly to the tune of a few screws.

02 Overclock Raspberry Pi (Optional)

Emulation can be demanding, so GPU and CPU overclocking makes sense, although it’s not absolutely necessary for this project. In a Terminal, type:

https://www.libretro.com/index.php/category/retroarch-disc-project/

And add the following lines:

over_voltage=6
arm_freq=1750
gpu_freq=700

These were stable during testing, but if Raspberry Pi fails to boot, power-cycle it and hold down SHIFT to boot into recovery mode. Then knock the settings down a bit. Here is further information on overclocking Raspberry Pi 4. If you overclock, you should use a stand or, better still, an active or passive cooling case. A FLIRC Raspberry Pi 4 Case worked well here.

03 Enable OpenGL

We’ll want OpenGL support for some emulators, such as PCSXR, In a Terminal, enter:

https://flirc.tv/more/raspberry-pi-4-case

Select Advanced Options &gt; GL Driver &gt; GL (Fake KMS), then exit
and allow the system to reboot. Open /boot/config.txt and make sure the following option is present and not commented out:

dtoverlay=vc4-fkms-v3d

04 Drop your resolution

Dropping your display resolution is an easy way of improving emulator performance. If you’re using a standard 1920×1080 widescreen monitor, you won’t need that resolution to play older games. Open the menu and go to Preferences > Screen configuration and set your resolution to 720×576 (or 640×480) if you either have a 4:3 display or can live with a bit of screen stretching in exchange for smooth full-screen graphics. Choose 1280×720 if you don’t mind playing in a window on emulators that can’t do aspect ratio correction.

05 Connect an elderly TV (Optional)

A 4:3 aspect ratio display is ideal here, and older display tech has the edge for 1990s console and computer games, too. Using a CRT TV rather than a modern LCD flatscreen can improve graphical quality as sprite and even 3D graphics of the era were optimised to work with the display artefacts of CRT.

Raspberry Pi supports composite video out. Connect a 4-pole 3.5mm AV cable to the 3.5mm port on Raspberry Pi and connect the other end to your TV. Using a composite to SCART adapter can improve picture stability. Note that Raspberry Pi’s 4-pole connector expects video to be connected to the sleeve and ground to ring 2, so ensure that you use a fully compatible cable. The wrong cable selection can result in non-functional sound, misordered cables, or even damage to your hardware.

06 Output composite video (Optional)

If you’re using a typical 4:3 PAL TV, make the following changes to /boot/config.txt to correctly position your display – small alterations may be required for different models. disable_overscan=0
overscan_left=16
overscan_right=16
sdtv_mode=2 In a Terminal, enter:

sudo raspi-config

then go to Advanced Options, Pi 4 Video Output, and Enable analogue TV output. Finish and reboot.

07 Mount a CD in DOSBox

If you’ve been following these tutorials, you may already have DOSBox or DOSBox-X installed. If not, at a Terminal:

sudo apt install dosbox
dosbox

To mount a disc at the DOS prompt, type:

mount D /media/YourDiscName/ -t cdrom -usecd
0 -ioctl

To unmount a disc in DOSBox, type:

mount -u D

By default, each individual disc has to be manually mounted in DOSBox, as mount point names are automatically generated based on the volume name of the disc. This can be a problem if you need to swap DOS CDs during play or installation.

08 Create a fixed mount point

To work around this, we can use the

pmount

command. From the Terminal, let’s first make sure it’s installed and then configure it:

sudo apt install pmount
sudo mousepad /etc/pmount.allow

Add the following line to the file, then save and exit:

/dev/sr0

On the desktop, open File Manager. Go to Edit > Preferences > Volume Management and untick all the Auto-mount options. Reboot Raspberry Pi.

09 Mount and swap CDs

Now, to mount a disc, insert it, open a Terminal window and type:

pmount /dev/sr0

To unmount it:

pumount /dev/sr0

Repeat the first

pmount

command to mount a new disc. Now, every disc will have a fixed mount point of

/media/sr0/

This means that, in DOSBox, you’ll just need to mount

D/media/sr0/

once. When you want to swap discs, whether at the DOS prompt or in-application, hop over to a Linux Terminal window, run through the

pmount

commands and then, back in DOSBox, press CTRL+F4 to update cached information about your mounted drives.

10 Play original discs

PCSXR – the R stands for either Reloaded or ReARMed, depending on which version you’re using – is an open-source emulator. It also has a genuinely good emulated bios, so you don’t need to download anything dodgy to make it work. The desktop version works best for original discs. Open a Terminal and type:

sudo apt install pcsxr

It can run games including Final Fantasy VII, Silent Hill, GTA, Sheep, and Resident Evil either perfectly or with only minor errors, but you’ll have to adjust some settings first.

11 Configure PCSXR’s graphics

Go to the Configuration menu and select Plugins &amp; BIOS. From the Graphics pull-down. Select OpenGL Driver 1.1.78. Click on the window icon directly to the right of the pull-down.

Starting with the Windows options tab, assuming you’re using the PAL resolution we configured, enter a width of 720, a height of 576, and tick the Fullscreen box. On the Textures tab, set Quality to Don’t care, Filtering to None, and HiRes Tex to None.

In the Framerate tab, ensure that Use FPS limit is ticked and set to auto-detect. Moving to the Compatibility tab, select Standard offscreen drawing, a Black framebuffer, and Emulated Vram for framebuffer access. Make sure the Mask bit and Alpha multipass boxes are ticked.

In the Misc tab, tick Untimed MDECs, Force 15 bit framebuffer updates, and Use OpenGL extensions. The Special game features tab includes game-specific options, such as battle cursors for Final Fantasy VII. Click Okay to save your changes.

12 Configure PCSXR’s sound and CD-ROM

Click on the window icon next to the Sound pulldown in the configuration window. Set Volume to Low, Reverb to Off, and Interpolation to None. Unsick everything except Single channel sound. Click Close, then open the CD-ROM settings. Set read mode to Normal (No Cache), Spindown time to 2 minutes, Cdrom Speed to 2min, and tick Emulated subchannel read. While you may need to adjust these settings for individual games or experiment with higher resolutions, this combination allows the vast majority of titles to run reasonably smoothly from their original discs. To test this, insert a disc into the drive, wait for it to load, then click on the CD icon at top left of the PCSXR window.

Catch KJ on Twitter @KJOrphanides

Reading Time: 3 minutes

It has considerable heft to withstand the rigours of the classroom. We measured the base
unit at 100×130×35mm and weighed it in at 397g.The GPIO sockets (with BCM numbering) break out to the top of the case alongside a small
120×64 OLED display and four control buttons, a built-in battery, and a speaker. You gain a second USB-C port for the upcoming pi-top Bluetooth Keyboard and FHD Touch
Display. Which promises to transform pi-top [4] into a touchscreen laptop.

Battery and screen

It’s the only case we’ve seen that contains a built-in battery and display. Making pi-top [4]
good for mobile use and also acts as power redundancy. It takes around an hour to charge
and lasts for around five hours of use. The small 128×64 OLED displays information on the battery level, CPU load, and network
connection. We were glad to discover an OLED and Button API in the documentation. The ‘ptoled’ module enables you to draw text, images and GIFs to the display, and plot and draw shapes.

Built-in cooling

pi-top [4] includes a fan that automatically adjusts its speed according to the CPU
temperature. We tested it with Stressberry and found that pi-top [4] idled at 35°C, maxing out under stress at 45°C (with an ambient temperature of 14°C). We overclocked it and ran pi-top [4] at 2GHz and the temperature maxed out at 56°c. At all
times the fan remained at a constant low non-intrusive spin, with speed controlled by the pi-top Hub. Reconnecting the fan to a second jumper enables manual control.

Installation

Installing Raspberry Pi inside pi-top [4] took around five minutes. Wil Bennett, pi-top’s
director of technology, has a YouTube video that walks you through the installation process. pi-topOS Solaris is a feature-packed operating system built on top of Raspberry Pi OS (32-
bit) ‘Buster’. It’s possible to use stock Raspberry Pi OS and control the pi-top hardware. We used this script:

echo "deb http://apt.pi-top.com/pi-top-os sirius main contrib non-free" | sudo tee /etc/apt/sources.list.d/pi-top.list &> /dev/null curl https://apt.pi-top.com/pt-apt.asc | sudo apt-key add sudo apt update sudo apt install --no-install-recommends -y pt-device-manager pt-sys-oled pt-firmware-updater sudo reboot

We had to install a firmware update to get the stock Raspberry Pi OS working; pi-top
assures us the final version will ship with the firmware installed. On the whole, we really like pi-top [4]. A lot more than we expected. The price remains a
hurdle, costing four times more than the Argon One. However, it has a range of unique features that make a compelling case for the additional cost and there’s no arguing with the build quality.

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Raspberry Pi 400 packs a measurable speed boost over Raspberry Pi 4, thanks to a clever passive cooling system which offers enough headroom for a processor jump to 1.8GHz. Join us as we dive into the latest, and most impressive, Raspberry Pi ever made.

Raspberry PI 400 specifications

• Price: £65 / $70 (Raspberry Pi 400), £93.00 / $100 (Raspberry Pi 400 Personal Computer Kit)

• SoC: Broadcom BCM2711C0 quad-core A72 (ARMv8-A) 64-bit @ 1.8GHz

• GPU: Broadcom VideoCore VI

• RAM: 4GB LPDDR4 SDRAM

• Networking: 2.4 GHz and 5 GHz 802.11b/g/n/ac wireless LAN, gigabit Ethernet

• Bluetooth: Bluetooth 5.0, Bluetooth Low Energy (BLE)

• GPIO: 40-pin GPIO header, populated

• Storage: microSD

• Ports: 1× USB Type-C power input, 2× micro-HDMI 2.0, 1× USB 2.0, 2× USB 3.0, 1× RJ45 Ethernet, 1× Kensington locking slot

• Cooling: Built-in passive heatsink

• Dimensions: 286mm × 122mm × 23.7mm, 385g

Where to buy Raspberry Pi 400

Click here for a full list of Raspberry Pi 400 resellers

Raspberry Pi 400 Personal Computer Kit

You can buy Raspberry Pi 400 on its own, or as part of a Personal Computer Kit bundle with all the accessories you need. Inside the box you’ll find:

Meet Raspberry PI 400

On the first inspection, Raspberry Pi 400 is deceptively similar to the Raspberry Pi keyboard and hub. It features the same high-quality keyboard.

Around the back of Raspberry Pi 400

The rear of Raspberry Pi 400 tells a different story, with an array of sockets and connectors. Inside Raspberry Pi 400 is hardware based upon Raspberry Pi 4, but with a different design to reposition all the connections.

40-pin GPIO header

The 40-pin GPIO header is used to connect Raspberry Pi 400 to electronic devices and to experiment with electronics and coding. Look closely and you’ll see PIN1 and PIN40 imprinted on the case next to the first and last pin.

Using HAT hardware with Raspberry Pi 400

Raspberry Pi 400 has the same 40-pin GPIO header as all current Raspberry Pi models. Only now it’s positioned on the rear of the case.

You can connect HAT hardware directly to the 40-pin GPIO header, but it will be pointing backwards and down. A ribbon cable can be used to extend the GPIO pins and most will connect to Raspberry Pi 400 and extend with the pins facing upwards. You can pick up ribbon cables from The Pi Hut and other stores for around £3.

Here we’re using a 40 Pin GPIO Ribbon Cable – Rainbow 150mm from The Pi Hut (£3).

Raspberry Pi 400 sockets and connections

microSD socket

This push-click microSD socket acts as the main drive. A 16GB microSD card with Raspberry Pi OS pre-installed is included in the box. Ensure the microSD card is inserted and power up to start Raspberry Pi 400.

2x micro HDMI

Two micro HDMI connectors are used to connect Raspberry Pi 400 to up to two 4K monitors. Raspberry Pi tell us they’re „happy with the micro HDMI connector form factor“ and there would be no way to support dual display with full-size connectors. A micro HDMI to HDMI cable is included in the Raspberry Pi 400 personal computer kit.

USB-C power

Raspberry Pi 400 is powered via this USB-C Power connection using a Raspberry Pi 15.3W USB-C Power Supply (included in the Raspberry Pi 400 personal computer kit).

USB 3.0

Two USB 3.0 sockets are used to connect devices requiring fast throughput, such as external storage drives.

USB-A 2.0

A single USB 2.0 socket is provided; typically it is used with the included mouse.

Gigabit Ethernet

Gigabit Ethernet provides a fast direct network connection.

Kensington lock socket

Secure Raspberry Pi 400 to a table with the security lock socket.

Inside Raspberry Pi 400

Built entirely into the keyboard, Raspberry Pi 400 keeps clutter to a minimum while simplifying setup – and if you buy the bundled version, it even comes with a Raspberry Pi OS microSD card pre-installed to get you up and running as quickly as possible.

The underside of the case, which clips in place using no screws, includes two ventilated sections to let the built-in heatsink cooling system breathe. A QR Code with the serial number is included in case you ever need to contact support.

Inside Raspberry Pi 400, the custom heatsink takes up almost the entire casing. Connected to the system-on-chip with a thermal pad, the heatsink works silently to keep Raspberry Pi 400 from thermally throttling. This enables the processor to run at a faster 1.8GHz base speed.

Under the heatsink, the printed circuit board uses a very different layout to previous Raspberry Pi models. Long and thin, the board has Ethernet hardware at its left, the USB and HDMI ports, the silver system-on-chip in the middle, the GPIO and keyboard connectors, and ends at the right with the wireless LAN and Bluetooth radio.

Opening Raspberry Pi 400

Open your Raspberry Pi 400 carefully! There are no screws, and it just clips into place all around the four sides of the body. Put a spudger (or a plectrum) between the two halves and slide until you feel a clip, then push to release; keep doing it until all clips have been freed and the two halves are apart. Remove the four screws to detach the heatsink.

Benchmarking Raspberry Pi 400

With 300MHz of extra clock speed, Raspberry Pi 400 is no slouch. Raspberry Pi 400 isn’t just an entirely new form factor and Raspberry Pi’s first integrated design: it’s also the fastest Raspberry Pi model ever released. A large metal heatsink, running almost the entire width of the casing, coupled with a roomier printed circuit board means Raspberry Pi 400’s system-on-chip ships clocked at 1.8GHz (one billion eight hundred million cycles per second) – up from Raspberry Pi 4’s 1.5GHz.

The additional speed can be felt in everything from web browsing and image editing to running Python programs, and it doesn’t come at the cost of compatibility: Raspberry Pi 400 is fully compatible with all software and operating systems which work on Raspberry Pi 4, and older models too.

It can also use less power: while the extra 300MHz means Raspberry Pi 400 draws more electricity than Raspberry Pi 4 under load, it finishes more quickly – and not needing an external USB keyboard means it uses less power at idle, too.

For the majority of use-cases, Raspberry Pi 400 is now the machine to beat – but those working on embedded projects will find the more compact Raspberry Pi 4, with its Display Serial Interface (DSI) and Camera Serial Interface (CSI) ports and Power over Ethernet (PoE) capabilities, is still the go-to model.

See also: Raspberry Pi 4 benchmarks

Raspberry Pi 400 benchmark testing: Linpack (higher is better)

Originally developed for supercomputers, this synthetic benchmark – ported to Raspberry Pi OS by Roy Longbottom – offers a look at best-case performance gains between models. Three versions of the benchmark are compared: Single Precision (SP), Double Precision (DP), and a Single Precision variant which uses the accelerated Arm NEON instructions available since Raspberry Pi 2.

More benchmarks and engineering interview in The MagPi magazine issue #100

We’ve got all the Raspberry Pi 400 information you could ask for in The MagPi magazine issue #100. On sale 26 November 2020. We have an in-depth interview with Eben Upton, CEO of Raspberry Pi and co-creator of the Raspberry Pi computer, and Simon Martin, Senior Principal Hardware Engineer at Raspberry Pi and designer of Raspberry Pi 400. Plus more detailed benchmarks and thermal testing of Raspberry Pi 400. Click here to subscribe to The MagPi and be sure not to miss a single issue.

Reading Time: 3 minutes

“I’ve always loved pinhole cameras,” he tells us. “As I played with [them], I wondered if I
could create a camera with hundreds of holes instead of a single point of light. That little
idea virus took hold and eventually I found myself buying out Wal-Mart’s entire inventory of
straws to test the idea.”

He worked on the new camera for about a year, building three prototypes before arriving at
the final design. “It’s funny how ideas seem like they will work in your head, but then when
you build it in real life, things fail in unusual ways. For example, I went to great lengths to
find the right surface for the image to be projected on inside the camera. At one point I
debated destroying a large TV screen because I thought the matte glass of the TV was
what would work. In the end, the material that worked best was ordinary wax paper. You
just never know what will work until you experiment.”

Points of light

Adrian explains the basics of how the camera works: “Think of a straw as a telescope.
Look through it and you see a tiny part of the bigger picture. Stack thousands of straws
and all those points of light add up to make a bigger picture. To capture the picture, the
light from each straw lands on a semi-transparent surface inside the camera. I take a
picture of that projection to get the final image.”

Exposure times range from one to six seconds. “It’s a guessing game,” he says, “but the
Raspberry Pi gives me a rough preview. As far as focus, the closer things are to the
straws, the clearer they appear. Focusing comes down to getting as close to the subject as
I can.”

Adrian reveals that when he heard about the new High Quality Camera earlier this year, he
knew he had to try it. “I’ve always wanted to build my own digital camera. Old film cameras
are easy to take apart and modify, but digital cameras are black boxes. Until Raspberry
Pi’s High Quality Camera, it has been virtually impossible to build your own digital camera.
Now the sky’s the limit.”

A Lego mount enables easy attachment of the Raspberry Pi HQ Camera to any of the
prototypes. “Once I screwed the 6mm Raspberry Pi lens to a 6×6 lego brick it made it
easier to play with,” he says. “Lego is a quick and easy way to hold things in place as you
are prototyping.”

Public display

The public reaction to the camera has been very positive. “People’s first response is
skepticism because it sounds like such a strange thing,” says Adrian. “But when they see
the images it creates, they are won over. They realise it isn’t a gimmick, it’s a way to create
images that are unlike anything else. And now that I am developing a following on
Instagram (@ade3), it is rewarding to get kudos from people outside my small circle of
friends and family.”

The camera is ideal for portraits and eventually he wants to have a show where it can be
in the gallery alongside the portraits taken with it. “Right now the camera still requires me
to be very hands-on, but eventually I think I can to get it to a point where anyone could
walk up to the camera and take a selfie. I like the idea of the camera existing on its own
without me being there to operate it.”

Reading Time: 2 minutes

Compute Module 4

Packing the power of Raspberry Pi 4 with an embedded form factor, Compute Module 4 is an incredible update for engineers and professionals. The most powerful Compute Module ever made packs a PCI Express lane, eMMC storage, and a quad-core ARM Cortex-A72 processor. We’ve got in-depth information about this new computer, plus benchmark tests and information about the new carrier boards.

Coffee Stirrer Camera

Adrian Hanft has built an innovative camera that uses 23,248 coffee stirrer straws and a Raspberry Pi High Quality Camera to capture stunning, and unique, pictures. We talk to him about building experimental photography builds with Raspberry Pi.

Build a retro CD-ROM console

KG has been building a range of retro consoles for us in recent months, each one getting more and more advanced. This month KG delves into the world of CD-ROM gaming and multimedia entertainment systems. Attach a CD/DVD drive to your Raspberry Pi and get ready to (re)discover a world of classic entertainment.

Holiday projects for a festive home

Get ready for the holidays with our guide to decorations, lights, sound, remote control, glitz and glamour. We’ve put together a selection of fantastic community projects that you can use to bedeck your home for the festive season.

Stellina review

Rob goes hands-on with a high-powered Raspberry Pi telescope. Stellina whirred and tracked across the night sky and took photographs of Saturn for us. It’s a magical piece of kit.

Christina Foust interview

One of the creators of the current Digital Making at Home streams tells us how she went from teacher to a different kind of teacher.

Reading Time: < 1 minute

Save 37% off the cover price with a subscription to The MagPi magazine. Try three issues for just £5, then pay £25 every six issues. You’ll save money and get a regular supply of in-depth reviews, features, guides and other PC enthusiast goodness delivered directly to your door every month.

Subscribe

Reading Time: 3 minutes

The University of Surrey student got the chance to work on a live CubeSat project with Surrey Space Centre, drawing on his undergraduate dissertation research. The AAReST(autonomous assembly of a reconfigurable space telescope) mission he worked on takes a modular approach to setting up a large-scale telescope in space. Its dual-redundant flight computer is equipped with two Compute Modules. Alex worked on its PCB (printed circuit board). 

Taking the helm 

The project began in 2014, soon after the launch of the original Raspberry Pi Compute Module. This made a CubeSat board with redundant devices viable. “Redundancy is a common way to increase the reliability of space hardware. It has been used in the computers of Mars Rovers and the Space Shuttle,” Alex notes. “The idea is that if one system fails or becomes unresponsive, another can take over and continue its task.” This project was covered on the Raspberry Pi blog back in 2015. 

Alex has been working on its fourth iteration. AAReST will use “a WiFi inter-satellite link to allow multiple spacecraft to rendezvous,” he explains. “Imagine flying into space one day and being able to connect to a satellite from your phone to conduct maintenance activities.” 

Raspberry Pi works well because of its low cost and compact size. It’s a good alternative to the significant expense of a ‘radiation-hardened’ device that can withstand the extreme temperature of near space. “Raspberry Pi has many attractive characteristics for a COTS (commercial, off the shelf) flight computer,” says Alex. “It is low-cost and compact, more powerful than comparable microcontrollers, and has excellent support from the electronics and hobbyist community.

“From an engineering perspective,” he adds, its “self-contained processor system can be integrated into an application without needing to worry about hard-to-implement supporting components.

“The Compute Module’s edge connector gives access to the GPIO, USB, and camera interfaces, providing the flexibility to directly integrate a Raspberry Pi into another application.”

Built-in redundancy

 Alex began with a partially completed blueprint from a previous student, but says this was largely a “clean sheet project”. Having been tasked with adding a cross-switched Raspberry Pi camera function and improving the system monitoring and control, he realised an integrated USB WiFi chipset would be beneficial. The Compute Modules run identical images of Raspberry Pi OS Lite (32-bit). In future, custom software code will run the dual-redundant code, possibly using Docker.

“I needed a stable software platform for running basic benchmarks and interacting with the system. Both Compute Modules run identical images of Raspbian Buster Lite, with modified device tree blobs to initialise all required GPIO and buses on the right pins. During testing, pigpio was used to access the functions of I2C and UART buses.”

Alex explains, “The CubeSat flight computer includes an MSP430 microcontroller to detect hardware failures and switch to the backup systems as soon as possible, to avoid permanent hardware damage. If a radiation hit caused a latch-up fault in the active Raspberry Pi, it would create a short-circuit path between the supply and ground.” The CubeSat would then switch to the other on-board Raspberry Pi.

Reading Time: 3 minutes

In The MagPi magazine issue #99 (on sale 29 October 2020), Gareth Halfacree takes a deep dive into Compute Module 4’s specifications and performs benchmark testing. Subscribe to The MagPi magazine to get all the in-depth information delivered to your door.

The original Raspberry Pi Compute Module launched in April 2014 as a means to make it easier for engineers and professionals to put the power of Raspberry Pi into their designs. The compact Raspberry Pi Compute Module isn’t a single-board computer but a system-on-module (SOM) designed to be inserted into a carrier board.

In 2016, Raspberry Pi Compute Module 3 and Compute Module 3 Lite offered higher specifications, switching to the same processor as Raspberry Pi 3. Compute Module 3+ boosted specifications still further. 

And now Raspberry Pi Compute Module 4 and Compute Module 4 Lite make the jump to the same high-performance hardware as Raspberry Pi 4.

These are the most powerful Compute Modules ever made. Eben Upton, CEO of Raspberry Pi trading and Raspberry Pi co-creator talks about Compute Module 4 in this Raspberry Pi blog post.

Meet Raspberry Pi Compute Module 4

Raspberry Pi Compute Module 4 uses a new form factor, swapping the SODIMM edge connector of earlier models to two high-density connectors on the underside. It’s a necessary change that brings all the features of the module to the Carrier Board.

This requires a change in the pins which connect the module to the carrier board. While both systems have 200 pins, the new connector is smaller and adds compatibility with new Raspberry Pi features, like the second HDMI port and PCI Express.

This means Raspberry Pi Compute Module 4 isn’t compatible with carrier boards designed for Raspberry Pi Compute Module 3.

The new SoC improves performance, the additional RAM makes it possible to work with more complex applications, and high-speed PCI Express connectivity means carrier boards have access to significantly more bandwidth.

Compute Module 4 specifications

• SoC: Broadcom BCM2711C0 quad-core ARM Cortex-A72 (ARMv8-A) 64-bit @ 1.5GHz

• GPU: Broadcom VideoCore VI

• RAM: 1GB, 2GB, 4GB, or 8GB LPDDR4 SDRAM

• Networking: Optional 2.4 GHz and 5 GHz 802.11b/g/n/ac Wi-Fi, Gigabit Ethernet PHY

• Bluetooth: Optional Bluetooth 5.0 and Bluetooth Low Energy (BLE)

• GPIO: Carrier board dependent

• Interfaces: PCI Express, 2× DSI, 2× CSI, 2× HDMI

• Storage: External (CM4 Lite); on-board 8GB/16GB/32GB eMMC (CM4)

• Ports: Hirose U.FL antenna connector, 2× 100-pin high-density connectors

• Dimensions: 55 mm × 40 mm × 4.5mm, 12g (exc. carrier board)

Compute Module Carrier boards

Unlike other models, Raspberry Pi Compute Module 4 has no connectors of its own – bar the U.FL antenna connector and the two high-density connectors on the underside. Instead, it relies on a carrier board – and the features available will depend on what features the carrier board breaks out.

Raspberry Pi Compute Module 4 Input/Output (IO) Board is an open-source design. It is designed to help developers get started: it brings out features including two full-size HDMI ports, Gigabit Ethernet, two USB ports, a 40-pin general-purpose input/output (GPIO) header, a Power over Ethernet (PoE) header, two DSI ports, two CSI ports for cameras, a PCI Express slot, and more.

Other carrier boards compatible with Raspberry Pi Compute Module 4 may be specialised for particular tasks, offering specific features or adding extra hardware of their own. Designers can tailor the carrier board to a particular task, but all carrier boards will be mechanically compatible with all Raspberry Pi Compute Module 4 models.

The MagPi issue #99 is on sale 29 October with in-depth benchmark testing for Compute Module 4. Buy your copy from the Raspberry Pi Press Store or subscribe now to get The MagPi magazine delivered to you door every month.

Reading Time: 6 minutes

Kit you’ll need

• Mopidy Music System

• Hi-Berry DAC+ Zero

• Case (optional)

See also: Build a home music system with Raspberry Pi and Make a audio system with Mopidy

Tip! Choose your DAC

There are a wide range of digital-audio convertors out there catering for every budget from £12 to thousands – choose wisely.

Going multi-room

Sure, playback from our Mopidy setup is great, but you don’t want to be carrying that setup around the house. With Snapcast we can play music anywhere in perfect sync so you can wander around your home without interruption. This clever piece of open-source software sends out audio in ‘frames’, each one with a time code attached. Any device that’s part of the stream matches the frame’s time code to its own internal clock to ensure playback happens at the same time, providing in-sync audio. The only downside is a short delay in starting playback as everything syncs up.

Snap to it

Before we can add Snapcast clients, our original Mopidy needs to become one itself, so it can keep in sync with everything else. We start by installing the Snapcast client and server on the same machine (it’s effectively streaming to itself). Enter the following on the command line to download the client:

wget https://github.com/badaix/snapcast/releases/download/v0.20.0/snapclient_0.20.0-1_armhf.deb

sudo dpkg -i snapclient_0.20.0-1_armhf.deb

If you get an error here, run this to fix it:

sudo apt -f install

This automated install sets everything up and will restart the service on reboot.

Snappy service

We have the client running on your Mopidy system, but nothing to serve music. So, now install the server:

wget https://github.com/badaix/snapcast/releases/download/v0.20.0/snapserver_0.20.0-1_armhf.deb

sudo dpkg -i snapserver_0.20.0-1_armhf.deb

This will also restart on boot. The client will automatically find the server as its local. Now tell Mopidy to send its audio stream to the Snapcast server instead of the DAC.

sudo nano /etc/mopidy/mopidy.conf

Change…

output = autoaudiosink

…to (on one line):

output = audioresample ! audioconvert ! audio/x-raw,rate=48000,channels=2,format=S16LE ! wavenc ! filesink location=/tmp/snapfifo

Now restart Mopidy:

Tell Iris about it

Iris comes with full control over the Snapcast system. After restarting Mopidy, go to the Iris interface and into Settings. You’ll see a Snapcast icon. Click on it and then click ‘Enable’. You should see a ‘Connected’ message appear. There will also be a group which represents your local Mopidy setup. Click the group to rename it to something memorable. Before proceeding further, make sure that playback still works. It’ll take a second or two longer to start as Snapcast syncs up, but should otherwise be unaffected. If it works well, your local Mopidy setup is complete.

Just add clients

Your system is now in effect streaming to itself, which means it can play in sync with other devices, so let’s add one. We’re using the HiFiBerry DAC+Zero, a great DAC for a small price. Start by connecting the DAC to a Raspberry Pi Zero W, ideally using standoffs to ensure a secure fit. Install Raspberry Pi OS Lite on this device as we’re going to be running it headless. Using raspi-config make sure you’ve configured wireless LAN and set a suitable hostname. Now update everything to the latest version using:

sudo apt -y update && sudo apt -y full-upgrade

Make some noise

To enable the DAC+ Zero, get command-line access to your Raspberry Pi Zero W (using SSH or connect up a monitor and keyboard) and edit the main configuration file:

sudo nano /boot/config.txt

Near the end of the file, find the line reading:

dtparam=audio=on

Delete it (or comment out with a #) and add:

dtoverlay=hifiberry-dac

Save (CTRL+X) and reboot your computer. Once back up, connect the phono sockets on the DAC to an amplifier and test the output:

aplay /usr/share/sounds/alsa/Front_Center.wav

If everything is working well, a nice person will say “front centre”.

Join the band

To get streaming working, we now repeat the process for installing the Snapcast client. Start by downloading and installing the client:

wget https://github.com/badaix/snapcast/releases/download/v0.20.0/snapclient_0.20.0-1_armhf.deb

sudo dpkg -i snapclient_0.20.0-1_armhf.deb

If you see errors at the end of the process with the line ‘dependency problems – leaving unconfigured’, run the following command:

sudo apt -f install

This will detect and install all the dependencies required and then finish configuration. Snapcast will be configured to automatically start on boot.

Configure and test

The Snapcast client is now running, but we need to tell it where the server is. Edit the configuration file:

sudo nano /etc/default/snapclient

Find the line that reads SNAPCAST_OPTS=““ and add your Mopidy server hostname as follows:

SNAPCLIENT_OPTS="--host jukebox.local”

Replace ‘jukebox.local’ with whatever you named your server. Save and exit, then restart the client:

sudo systemctl restart snapclient

In a web browser, open up Iris on your main server and go to Settings, then click on Snapcast. You should see a new group (something like ‘Group 8ec’); that’s your device.

Play, tweak, repeat

Now try playing something from Mopidy with your new client hooked up to an amplifier or active speaker. Everything should be in sync. If not, you can adjust latency under your group settings to fine-tune the playback. At the bottom of the screen, you can click the speaker icon to control which devices are playing and set their individual volume levels.

You can add as many Snapcast clients as you like. It’s a great use for an older Raspberry Pi and you don’t have to use a DAC, you can just use the standard audio/video jack to an active speaker. We built another client using Pimoroni’s Speaker pHAT and a battery for portable tunes.

Add some Apple

Snapcast supports multiple streams, allowing clients to switch between them. We can add Apple AirPlay 2 support as a Snapcast stream that runs alongside Mopidy. We can’t just install a package, though: we have to build and install Shairport Sync with the following commands:

cd

sudo apt install build-essential git xmltoman autoconf automake libtool libpopt-dev libconfig-dev libasound2-dev avahi-daemon libavahi-client-dev libssl-dev libsoxr-dev

git clone https://github.com/mikebrady/shairport-sync.git

autoreconf -fi

./configure --with-stdout --with-avahi --with-ssl=openssl --with-metadata

make

sudo make install

Multistream!

The final step is to configure Snapcast to enable Shairport Sync as a stream. Open up the Snapcast configuration file as follows:

sudo nano /etc/snapserver.conf

In the section starting [stream] you’ll see an entry starting stream =. Directly under there add the following line:

stream = airplay:///shairport-sync?name=Airplay&devicename=Jukebox

(You can change the names to anything you like.) Now restart everything:

sudo systemctl restart snapserver.service

sudo systemctl restart mopidy.service

In Iris, go to the Snapcast settings and change the default stream to AirPlay. You can now push audio from iOS devices and Macs to your music system or any other Snapcast client.

Going further

If you’ve played along and built this setup, you how have a pretty sweet audio player setup. The great thing about this project is the wider range of budgets and platforms for which it caters. You can reuse older hardware, upcycle speakers, and turn just about anything with a processor into a streaming client. You can also get HATs with pure digital S/PDIF or coaxial output so you can use an amplifier’s DAC if you prefer. How about using a USB audio capture device to stream audio around the house from your record player? As ever, it’s over to you.

Tip! DAC’s not for me

If you’re on a tight budget, you don’t need a DAC at all. The line-out found on board most Raspberry Pi computers will suffice for smaller projects.

Reading Time: 3 minutes

After helping out on Sonic Bikes, a sound art project started by Kaffe Matthews, they thought about bringing the bikes to Cornwall, “but it’s a dangerous place for cycling with very few cycle paths and narrow roads,” Amber tells us, “so we started talking about making a version for boats.”

With a background in wildlife conservation genetics, she thought it would be good to add some environmental sensors and try using it to gather underwater data. “So it’s gone from being a pure sound-art project on bikes, to something that has both sound-art and scientific purpose on kayaks. Kaffe’s now working on putting some of the environmental sensors onto the Sonic Bikes, so it’s going full circle.”

Environmental sensors

Each Sonic Kayak kit is equipped with four environmental sensors. Water temperature is measured using a digital thermometer, water cloudiness using a home-made sensor consisting of an LED and an LDR in a dark tube (the amount of light that hits the LDR is a measure of how cloudy the water is), underwater sound using a hydrophone, and above-water air pollution using a laser dust sensor.  There’s also a GPS unit to record the kayak’s geographical co-ordinates, which enables mapping of the environmental data gathered.

Sounds based on the data are played in real-time through waterproof Bluetooth speaker to the kayaker. “This does two things,” explains Amber. “Firstly, it gives people a real connection to the underwater world that is otherwise very hard to understand. Secondly, if you are interested in gathering a particular type of data, for example pollution coming from a large boat, if you can hear when you are entering a polluted area then it allows you to follow that data and collect exactly what you need.”

The system has also proven useful for people with visual impairments. “We’ve been working with an accessible kayak club to develop the system for navigation purposes, to allow people to kayak independently even if they have little or no sight.”

Electronics and water

The kit’s electronics – including a Raspberry Pi 3B and Arduino Nano – are housed in a Bopla Bocube plastic enclosure that fits into the rear of the kayak. The combination of electronics with salt water has proved problematic previously. “One of our earliest Sonic Kayak events was the British Science Festival in 2016, and on the second day the sea was very choppy and both kayaks capsized with the systems on them,” recalls Amber. “We watched all the electronics break apart and wash up on the beach, then almost instantly corrode due to the salt water, which was rather painful! Since then we’ve got very good with embedding electronics in resin, and using rubber seals for the sensor cables.”

While the data gathered so far by the project is proof-of-principle, it may well be of interest to professional researchers. “This type of data is really hard to get, particularly for places close to cliffs or in tidal estuaries, where it’s difficult to take large research boats,” says Amber. “Our system also means you can get very fine-scale data, as opposed to the broader scale sea temperature data you get from satellites, or the data you can get from attaching sensors to buoys.”

However, Amber says they’re more interested in getting it into the hands of people who want to use it to map their local environments. “We’ve started working on ways to visualise the data from the Sonic Kayaks on maps, and would love to make a portal where people can upload the data from their kayaking trips, and have it visualised automatically.”