Raspberry Pi Blog

This is the official Raspberry Pi blog for news and updates from the Raspberry Pi Foundation, education initiatives, community projects and more!

Tackling climate change and helping the community

In today’s guest post, seventh-grade students Evan Callas, Will Ross, Tyler Fallon, and Kyle Fugate share their story of using the Raspberry Pi Oracle Weather Station in their Innovation Lab class, headed by Raspberry Pi Certified Educator Chris Aviles.

Raspberry Pi Certified Educator Chris Aviles Innovation Lab Oracle Weather Station

United Nations Sustainable Goals

The past couple of weeks in our Innovation Lab class, our teacher, Mr Aviles, has challenged us students to design a project that helps solve one of the United Nations Sustainable Goals. We chose Climate Action. Innovation Lab is a class that gives students the opportunity to learn about where the crossroads of technology, the environment, and entrepreneurship meet. Everyone takes their own paths in innovation and learns about the environment using project-based learning.

Raspberry Pi Certified Educator Chris Aviles Innovation Lab Oracle Weather Station

Raspberry Pi Oracle Weather Station

For our climate change challenge, we decided to build a Raspberry Pi Oracle Weather Station. Tackling the issues of climate change in a way that helps our community stood out to us because we knew with the help of this weather station we can send the local data to farmers and fishermen in town. Recent changes in climate have been affecting farmers’ crops. Unexpected rain, heat, and other unusual weather patterns can completely destabilize the natural growth of the plants and destroy their crops altogether. The amount of labour output needed by farmers has also significantly increased, forcing farmers to grow more food on less resources. By using our Raspberry Pi Oracle Weather Station to alert local farmers, they can be more prepared and aware of the weather, leading to better crops and safe boating.

Raspberry Pi Certified Educator Chris Aviles Innovation Lab Oracle Weather Station

Growing teamwork and coding skills

The process of setting up our weather station was fun and simple. Raspberry Pi made the instructions very easy to understand and read, which was very helpful for our team who had little experience in coding or physical computing. We enjoyed working together as a team and were happy to be growing our teamwork skills.

Once we constructed and coded the weather station, we learned that we needed to support the station with PVC pipes. After we completed these steps, we brought the weather station up to the roof of the school and began collecting data. Our information is currently being sent to the Initial State dashboard so that we can share the information with anyone interested. This information will also be recorded and seen by other schools, businesses, and others from around the world who are using the weather station. For example, we can see the weather in countries such as France, Greece and Italy.

Raspberry Pi Certified Educator Chris Aviles Innovation Lab Oracle Weather Station

Raspberry Pi allows us to build these amazing projects that help us to enjoy coding and physical computing in a fun, engaging, and impactful way. We picked climate change because we care about our community and would like to make a substantial contribution to our town, Fair Haven, New Jersey. It is not every day that kids are given these kinds of opportunities, and we are very lucky and grateful to go to a school and learn from a teacher where these opportunities are given to us. Thanks, Mr Aviles!

To see more awesome projects by Mr Avile’s class, you can keep up with him on his blog and follow him on Twitter.

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Invent new sounds with Google’s NSynth Super

Discover new sounds and explore the role of machine learning in music production and sound research with the NSynth Super, an ongoing project from Google’s Magenta research team that you can build at home.

Google Open NSynth Super Testing

Uploaded by AB Open on 2018-04-17.

What is the NSynth Super?

Part of the ongoing Magenta research project within Google, NSynth Super explores the ways in which machine learning tools help artists and musicians be creative.

Google Nsynth Super Raspberry Pi

“Technology has always played a role in creating new types of sounds that inspire musicians — from the sounds of distortion to the electronic sounds of synths,” explains the team behind the NSynth Super. “Today, advances in machine learning and neural networks have opened up new possibilities for sound generation.”

Using TensorFlow, the Magenta team builds tools and interfaces that let artists and musicians use machine learning in their work. The NSynth Super AI algorithm uses deep neural networking to investigate the character of sounds. It then builds new sounds based on these characteristics instead of simply mixing sounds together.

Using an autoencoder, it extracts 16 defining temporal features from each input. These features are then interpolated linearly to create new embeddings (mathematical representations of each sound). These new embeddings are then decoded into new sounds, which have the acoustic qualities of both inputs.

The team publishes all hardware designs and software that are part of their ongoing research under open-source licences, allowing you to build your own synth.

Build your own NSynth Super

Using these open-source tools, Andrew Black has produced his own NSynth Super, demoed in the video above. Andrew’s list of build materials includes a Raspberry Pi 3, potentiometers, rotary encoders, and the Adafruit 1.3″ OLED display. Magenta also provides Gerber files for you to fabricate your own PCB.

Google Nsynth Super Raspberry Pi

Once fabricated, the PCB includes a table of contents for adding components.

The build isn’t easy — it requires soldering skills or access to someone who can assemble PCBs. Take a look at Andrew’s blog post and the official NSynth GitHub repo to see whether you’re up to the challenge.

Music and Raspberry Pi

The Raspberry Pi has been widely used for music production and music builds. Be it retrofitting a boombox, distributing music atop Table Mountain, or coding tracks with Sonic Pi, the Pi offers endless opportunities for musicians and music lovers to expand their repertoire of builds and instruments.

If you’d like to try more music-based projects using the Raspberry Pi, you can check out our free resources. And if you’ve used a Raspberry Pi in your own musical project, please share it with us in the comments or via our social network accounts.

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Hackspace magazine 6: Paper Engineering

HackSpace magazine is back with our brand-new issue 6, available for you on shop shelves, in your inbox, and on our website right now.

Inside Hackspace magazine 6

Paper is probably the first thing you ever used for making, and for good reason: in no other medium can you iterate through 20 designs at the cost of only a few pennies. We’ve roped in Rob Ives to show us how to make a barking paper dog with moveable parts and a cam mechanism. Even better, the magazine includes this free paper automaton for you to make yourself. That’s right: free!

At the other end of the scale, there’s the forge, where heat, light, and noise combine to create immutable steel. We speak to Alec Steele, YouTuber, blacksmith, and philosopher, about his amazingly beautiful Damascus steel creations, and about why there’s no difference between grinding a knife and blowing holes in a mountain to build a road through it.

HackSpace magazine 6 Alec Steele

Do it yourself

You’ve heard of reading glasses — how about glasses that read for you? Using a camera, optical character recognition software, and a text-to-speech engine (and of course a Raspberry Pi to hold it all together), reader Andrew Lewis has hacked together his own system to help deal with age-related macular degeneration.

It’s the definition of hacking: here’s a problem, there’s no solution in the shops, so you go and build it yourself!

Radio

60 years ago, the cutting edge of home hacking was the transistor radio. Before the internet was dreamt of, the transistor radio made the world smaller and brought people together. Nowadays, the components you need to build a radio are cheap and easily available, so if you’re in any way electronically inclined, building a radio is an ideal excuse to dust off your soldering iron.

Tutorials

If you’re a 12-month subscriber (if you’re not, you really should be), you’ve no doubt been thinking of all sorts of things to do with the Adafruit Circuit Playground Express we gave you for free. How about a sewable circuit for a canvas bag? Use the accelerometer to detect patterns of movement — walking, for example — and flash a series of lights in response. It’s clever, fun, and an easy way to add some programmable fun to your shopping trips.

We’re also making gin, hacking a children’s toy car to unlock more features, and getting started with robot sumo to fill the void left by the cancellation of Robot Wars.

HackSpace magazine 6

All this, plus an 11-metre tall mechanical miner, in HackSpace magazine issue 6 — subscribe here from just £4 an issue or get the PDF version for free. You can also find HackSpace magazine in WHSmith, Tesco, Sainsbury’s, and independent newsagents in the UK. If you live in the US, check out your local Barnes & Noble, Fry’s, or Micro Center next week. We’re also shipping to stores in Australia, Hong Kong, Canada, Singapore, Belgium, and Brazil, so be sure to ask your local newsagent whether they’ll be getting HackSpace magazine.

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Announcing Coolest Projects North America

The Raspberry Pi Foundation loves to celebrate people who use technology to solve problems and express themselves creatively, so we’re proud to expand the incredibly successful event Coolest Projects to North America. This free event will be held on Sunday 23 September 2018 at the Discovery Cube Orange County in Santa Ana, California.

Coolest Projects North America logo Raspberry Pi CoderDojo

What is Coolest Projects?

Coolest Projects is a world-leading showcase that empowers and inspires the next generation of digital creators, innovators, changemakers, and entrepreneurs. The event is both a competition and an exhibition to give young digital makers aged 7 to 17 a platform to celebrate their successes, creativity, and ingenuity.

showcase crowd — Coolest Projects North America

In 2012, Coolest Projects was conceived as an opportunity for CoderDojo Ninjas to showcase their work and for supporters to acknowledge these achievements. Week after week, Ninjas would meet up to work diligently on their projects, hacks, and code; however, it can be difficult for them to see their long-term progress on a project when they’re concentrating on its details on a weekly basis. Coolest Projects became a dedicated time each year for Ninjas and supporters to reflect, celebrate, and share both the achievements and challenges of the maker’s journey.

three female coolest projects attendees — Coolest Projects North America

Coolest Projects North America

Not only is Coolest Projects expanding to North America, it’s also expanding its participant pool! Members of our team have met so many amazing young people creating in all areas of the world, that it simply made sense to widen our outreach to include Code Clubs, students of Raspberry Pi Certified Educators, and members of the Raspberry Jam community at large as well as CoderDojo attendees.

 a boy showing a technology project to an old man, with a girl playing on a laptop on the floor — Coolest Projects North America

Exhibit and attend Coolest Projects

Coolest Projects is a free, family- and educator-friendly event. Young people can apply to exhibit their projects, and the general public can register to attend this one-day event. Be sure to register today, because you make Coolest Projects what it is: the coolest.

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Colour sensing with a Raspberry Pi

In their latest video and tutorial, Electronic Hub shows you how to detect colour using a Raspberry Pi and a TCS3200 colour sensor.

Raspberry Pi Color Sensor (TCS3200) Interface | Color Detector

A simple Raspberry Pi based project using TCS3200 Color Sensor. The project demonstrates how to interface a Color Sensor (like TCS3200) with Raspberry Pi and implement a simple Color Detector using Raspberry Pi.

What is a TCS3200 colour sensor?

Colour sensors sense reflected light from nearby objects. The bright light of the TCS3200’s on-board white LEDs hits an object’s surface and is reflected back. The sensor has an 8×8 array of photodiodes, which are covered by either a red, blue, green, or clear filter. The type of filter determines what colour a diode can detect. Then the overall colour of an object is determined by how much light of each colour it reflects. (For example, a red object reflects mostly red light.)

Colour sensing with the TCS3200 Color Sensor and a Raspberry Pi

As Electronics Hub explains:

TCS3200 is one of the easily available colour sensors that students and hobbyists can work on. It is basically a light-to-frequency converter, i.e. based on colour and intensity of the light falling on it, the frequency of its output signal varies.

I’ll save you a physics lesson here, but you can find a detailed explanation of colour sensing and the TCS3200 on the Electronics Hub blog.

Raspberry Pi colour sensor

The TCS3200 colour sensor is connected to several of the onboard General Purpose Input Output (GPIO) pins on the Raspberry Pi.

Colour sensing with the TCS3200 Color Sensor and a Raspberry Pi

These connections allow the Raspberry Pi 3 to run one of two Python scripts that Electronics Hub has written for the project. The first displays the RAW RGB values read by the sensor. The second detects the primary colours red, green, and blue, and it can be expanded for more colours with the help of the first script.

Colour sensing with the TCS3200 Color Sensor and a Raspberry Pi

Electronic Hub’s complete build uses a breadboard for simply prototyping

Use it in your projects

This colour sensing setup is a simple means of adding a new dimension to your builds. Why not build a candy-sorting robot that organises your favourite sweets by colour? Or add colour sensing to your line-following buggy to allow for multiple path options!

If your Raspberry Pi project uses colour sensing, we’d love to see it, so be sure to share it in the comments!

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AIY Projects 2: Google’s AIY Projects Kits get an upgrade

After the outstanding success of their AIY Projects Voice and Vision Kits, Google has announced the release of upgraded kits, complete with Raspberry Pi Zero WH, Camera Module, and preloaded SD card.

Google AIY Projects Vision Kit 2 Raspberry Pi

Google’s AIY Projects Kits

Google launched the AIY Projects Voice Kit last year, first as a cover gift with The MagPi magazine and later as a standalone product.

Makers needed to provide their own Raspberry Pi for the original kit. The new kits include everything you need, from Pi to SD card.

Within a DIY cardboard box, makers were able to assemble their own voice-activated AI assistant akin to the Amazon Alexa, Apple’s Siri, and Google’s own Google Home Assistant. The Voice Kit was an instant hit that spurred no end of maker videos and tutorials, including our own free tutorial for controlling a robot using voice commands.

Later in the year, the team followed up the success of the Voice Kit with the AIY Projects Vision Kit — the same cardboard box hosting a camera perfect for some pretty nifty image recognition projects.

For more on the AIY Voice Kit, here’s our release video hosted by the rather delightful Rob Zwetsloot.

AIY Projects adds natural human interaction to your Raspberry Pi

Check out the exclusive Google AIY Projects Kit that comes free with The MagPi 57! Grab yourself a copy in stores or online now: http://magpi.cc/2pI6IiQ This first AIY Projects kit taps into the Google Assistant SDK and Cloud Speech API using the AIY Projects Voice HAT (Hardware Accessory on Top) board, stereo microphone, and speaker (included free with the magazine).

AIY Projects 2

So what’s new with version 2 of the AIY Projects Voice Kit? The kit now includes the recently released Raspberry Pi Zero WH, our Zero W with added pre-soldered header pins for instant digital making accessibility. Purchasers of the kits will also get a micro SD card with preloaded OS to help them get started without having to set the card up themselves.

Google AIY Projects Vision Kit 2 Raspberry Pi

Everything you need to build your own Raspberry Pi-powered Google voice assistant

In the newly upgraded AIY Projects Vision Kit v1.2, makers are also treated to an official Raspberry Pi Camera Module v2, the latest model of our add-on camera.

Google AIY Projects Vision Kit 2 Raspberry Pi

“Everything you need to get started is right there in the box,” explains Billy Rutledge, Google’s Director of AIY Projects. “We knew from our research that even though makers are interested in AI, many felt that adding it to their projects was too difficult or required expensive hardware.”

Google is also hard at work producing AIY Projects companion apps for Android, iOS, and Chrome. The Android app is available now to coincide with the launch of the upgraded kits, with the other two due for release soon. The app supports wireless setup of the AIY Kit, though avid coders will still be able to hack theirs to better suit their projects.

Google has also updated the AIY Projects website with an AIY Models section highlighting a range of neural network projects for the kits.

Get your kit

The updated Voice and Vision Kits were announced last night, and in the US they are available now from Target. UK-based makers should be able to get their hands on them this summer — keep an eye on our social channels for updates and links.

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Start a CoderDojo with our free online training

You can now sign up to our newest free online course Start a CoderDojo to learn more about CoderDojo and how you can easily set up one of these free coding clubs for young people in your area. With less than two weeks until the course begins, we wanted to tell you about the course’s content and why the course’s creator put it together for you.

Start a CoderDojo || free online learning || Raspberry Pi Foundation

Get support and advice on how to grow your confidence in coding and start a CoderDojo for young people in your area.

What is CoderDojo?

CoderDojo is a global network of free, volunteer-led, community-based programming clubs for young people aged 7 to 17. There are currently more than 1700 Dojos running regularly across 75 countries. All of these clubs were started by individuals who are passionate about giving young people the opportunity to learn to code. Some people assume you need technical skills to start a Dojo, but that’s not true. The most important thing is that you can bring people together for a shared goal.

What is covered on the course?

The course was developed by Philip, CoderDojo’s Educational Content Lead. It gives those who think empowering young people to be tech creators is important the resources and supports to achieve that goal by starting a Dojo. Divided over three weeks and running for about four hours in total, the course provides practical advice and resources on everything you need to know to plan and run a fun, social, and creative coding club for young people.

“In the first week, you’ll look at what coding is, at the worldwide CoderDojo community of coding clubs, and at the creative approach CoderDojos take to helping young people learn to code. In week two, you’ll move on to setting up your Dojo with a team, a venue, and any needed materials. You’ll also look at how to find young people to attend. Week three wraps up the course by giving you sample plans for a Dojo session and a Dojo’s year, and we’ll be talking about how to grow and develop your Dojo over time as your attendees become better coders.”
— Philip

Who is the course for?

Anyone interested in enabling young people to be tech creators should take this course. Parents, teachers, librarians, IT professionals, youth workers, and others have all started Dojos in their community. They say that “it’s an amazing experience that led [them] to expand [their] personal horizons”, and that they “find it really rewarding”.

The course is free and open to all — if you’re interested, then sign up now.

If you’re already mentoring at a Dojo, the course is a great opportunity to revise what you’ve learnt, and a chance to share your insights with newcomers in the discussion sections. Parents and guardians who wish to learn more about CoderDojo and are considering getting involved are also more than welcome to join.

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The answers to your questions for Eben Upton

Before Easter, we asked you to tell us your questions for a live Q & A with Raspberry Pi Trading CEO and Raspberry Pi creator Eben Upton. The variety of questions and comments you sent was wonderful, and while we couldn’t get to them all, we picked a handful of the most common to grill him on.

You can watch the video below — though due to this being the first pancake of our live Q&A videos, the sound is a bit iffy — or read Eben’s answers to the first five questions today. We’ll follow up with the rest in the next few weeks!

Live Q&A with Eben Upton, creator of the Raspberry Pi

Get your questions to us now using #AskRaspberryPi on Twitter

Any plans for 64-bit Raspbian?

Raspbian is effectively 32-bit Debian built for the ARMv6 instruction-set architecture supported by the ARM11 processor in the first-generation Raspberry Pi. So maybe the question should be: “Would we release a version of our operating environment that was built on top of 64-bit ARM Debian?”

And the answer is: “Not yet.”

When we released the Raspberry Pi 3 Model B+, we released an operating system image on the same day; the wonderful thing about that image is that it runs on every Raspberry Pi ever made. It even runs on the alpha boards from way back in 2011.

That deep backwards compatibility is really important for us, in large part because we don’t want to orphan our customers. If someone spent $35 on an older-model Raspberry Pi five or six years ago, they still spent $35, so it would be wrong for us to throw them under the bus.

So, if we were going to do a 64-bit version, we’d want to keep doing the 32-bit version, and then that would mean our efforts would be split across the two versions; and remember, we’re still a very small engineering team. Never say never, but it would be a big step for us.

For people wanting a 64-bit operating system, there are plenty of good third-party images out there, including SUSE Linux Enterprise Server.

Given that the 3B+ includes 5GHz wireless and Power over Ethernet (PoE) support, why would manufacturers continue to use the Compute Module?

It’s a form-factor thing.

Very large numbers of people are using the bigger product in an industrial context, and it’s well engineered for that: it has module certification, wireless on board, and now PoE support. But there are use cases that can’t accommodate this form factor. For example, NEC displays: we’ve had this great relationship with NEC for a couple of years now where a lot of their displays have a socket in the back that you can put a Compute Module into. That wouldn’t work with the 3B+ form factor.

Back of an NEC display with a Raspberry Pi Compute Module slotted in.

An NEC display with a Raspberry Pi Compute Module

What are some industrial uses/products Raspberry is used with?

The NEC displays are a good example of the broader trend of using Raspberry Pi in digital signage.

A Raspberry Pi running the wait time signage at The Wizarding World of Harry Potter, Universal Studios.
Image c/o thelonelyredditor1

If you see a monitor at a station, or an airport, or a recording studio, and you look behind it, it’s amazing how often you’ll find a Raspberry Pi sitting there. The original Raspberry Pi was particularly strong for multimedia use cases, so we saw uptake in signage very early on.

An array of many Raspberry Pis

Los Alamos Raspberry Pi supercomputer

Another great example is the Los Alamos National Laboratory building supercomputers out of Raspberry Pis. Many high-end supercomputers now are built using white-box hardware — just regular PCs connected together using some networking fabric — and a collection of Raspberry Pi units can serve as a scale model of that. The Raspberry Pi has less processing power, less memory, and less networking bandwidth than the PC, but it has a balanced amount of each. So if you don’t want to let your apprentice supercomputer engineers loose on your expensive supercomputer, a cluster of Raspberry Pis is a good alternative.

Why is there no power button on the Raspberry Pi?

“Once you start, where do you stop?” is a question we ask ourselves a lot.

There are a whole bunch of useful things that we haven’t included in the Raspberry Pi by default. We don’t have a power button, we don’t have a real-time clock, and we don’t have an analogue-to-digital converter — those are probably the three most common requests. And the issue with them is that they each cost a bit of money, they’re each only useful to a minority of users, and even that minority often can’t agree on exactly what they want. Some people would like a power button that is literally a physical analogue switch between the 5V input and the rest of the board, while others would like something a bit more like a PC power button, which is partway between a physical switch and a ‘shutdown’ button. There’s no consensus about what sort of power button we should add.

So the answer is: accessories. By leaving a feature off the board, we’re not taxing the majority of people who don’t want the feature. And of course, we create an opportunity for other companies in the ecosystem to create and sell accessories to those people who do want them.

Adafruit Push-button Power Switch Breakout Raspberry Pi

The Adafruit Push-button Power Switch Breakout is one of many accessories that fill in the gaps for makers.

We have this neat way of figuring out what features to include by default: we divide through the fraction of people who want it. If you have a 20 cent component that’s going to be used by a fifth of people, we treat that as if it’s a $1 component. And it has to fight its way against the $1 components that will be used by almost everybody.

Do you think that Raspberry Pi is the future of the Internet of Things?

Absolutely, Raspberry Pi is the future of the Internet of Things!

In practice, most of the viable early IoT use cases are in the commercial and industrial spaces rather than the consumer space. Maybe in ten years’ time, IoT will be about putting 10-cent chips into light switches, but right now there’s so much money to be saved by putting automation into factories that you don’t need 10-cent components to address the market. Last year, roughly 2 million $35 Raspberry Pi units went into commercial and industrial applications, and many of those are what you’d call IoT applications.

So I think we’re the future of a particular slice of IoT. And we have ten years to get our price point down to 10 cents :)

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Build a house in Minecraft using Python

In this tutorial from The MagPi issue 68, Steve Martin takes us through the process of house-building in Minecraft Pi. Get your copy of The MagPi in stores now, or download it as a free PDF here.

Minecraft Pi is provided for free as part of the Raspbian operating system. To start your Minecraft: Pi Edition adventures, try our free tutorial Getting started with Minecraft.

Minecraft Raspberry Pi

Writing programs that create things in Minecraft is not only a great way to learn how to code, but it also means that you have a program that you can run again and again to make as many copies of your Minecraft design as you want. You never need to worry about your creation being destroyed by your brother or sister ever again — simply rerun your program and get it back! Whilst it might take a little longer to write the program than to build one house, once it’s finished you can build as many houses as you want.

Co-ordinates in Minecraft

Let’s start with a review of the coordinate system that Minecraft uses to know where to place blocks. If you are already familiar with this, you can skip to the next section. Otherwise, read on.

Minecraft Raspberry Pi Edition

Plan view of our house design

Minecraft shows us a three-dimensional (3D) view of the world. Imagine that the room you are in is the Minecraft world and you want to describe your location within that room. You can do so with three numbers, as follows:

  • How far across the room are you? As you move from side to side, you change this number. We can consider this value to be our X coordinate.
  • How high off the ground are you? If you are upstairs, or if you jump, this value increases. We can consider this value to be our Y coordinate.
  • How far into the room are you? As you walk forwards or backwards, you change this number. We can consider this value to be our Z coordinate.

You might have done graphs in school with X going across the page and Y going up the page. Coordinates in Minecraft are very similar, except that we have an extra value, Z, for our third dimension. Don’t worry if this still seems a little confusing: once we start to build our house, you will see how these three dimensions work in Minecraft.

Designing our house

It is a good idea to start with a rough design for our house. This will help us to work out the values for the coordinates when we are adding doors and windows to our house. You don’t have to plan every detail of your house right away. It is always fun to enhance it once you have got the basic design written. The image above shows the plan view of the house design that we will be creating in this tutorial. Note that because this is a plan view, it only shows the X and Z co-ordinates; we can’t see how high anything is. Hopefully, you can imagine the house extending up from the screen.

We will build our house close to where the Minecraft player is standing. This a good idea when creating something in Minecraft with Python, as it saves us from having to walk around the Minecraft world to try to find our creation.

Starting our program

Type in the code as you work through this tutorial. You can use any editor you like; we would suggest either Python 3 (IDLE) or Thonny Python IDE, both of which you can find on the Raspberry Pi menu under Programming. Start by selecting the File menu and creating a new file. Save the file with a name of your choice; it must end with .py so that the Raspberry Pi knows that it is a Python program.

It is important to enter the code exactly as it is shown in the listing. Pay particular attention to both the spelling and capitalisation (upper- or lower-case letters) used. You may find that when you run your program the first time, it doesn’t work. This is very common and just means there’s a small error somewhere. The error message will give you a clue about where the error is.

It is good practice to start all of your Python programs with the first line shown in our listing. All other lines that start with a # are comments. These are ignored by Python, but they are a good way to remind us what the program is doing.

The two lines starting with from tell Python about the Minecraft API; this is a code library that our program will be using to talk to Minecraft. The line starting mc = creates a connection between our Python program and the game. Then we get the player’s location broken down into three variables: x, y, and z.

Building the shell of our house

To help us build our house, we define three variables that specify its width, height, and depth. Defining these variables makes it easy for us to change the size of our house later; it also makes the code easier to understand when we are setting the co-ordinates of the Minecraft bricks. For now, we suggest that you use the same values that we have; you can go back and change them once the house is complete and you want to alter its design.

It’s now time to start placing some bricks. We create the shell of our house with just two lines of code! These lines of code each use the setBlocks command to create a complete block of bricks. This function takes the following arguments:

setBlocks(x1, y1, z1, x2, y2, z2, block-id, data)

x1, y1, and z1 are the coordinates of one corner of the block of bricks that we want to create; x2, y2, and z2 are the coordinates of the other corner. The block-id is the type of block that we want to use. Some blocks require another value called data; we will see this being used later, but you can ignore it for now.

We have to work out the values that we need to use in place of x1, y1, z1, x2, y2, z2 for our walls. Note that what we want is a larger outer block made of bricks and that is filled with a slightly smaller block of air blocks. Yes, in Minecraft even air is actually just another type of block.

Once you have typed in the two lines that create the shell of your house, you almost ready to run your program. Before doing so, you must have Minecraft running and displaying the contents of your world. Do not have a world loaded with things that you have created, as they may get destroyed by the house that we are building. Go to a clear area in the Minecraft world before running the program. When you run your program, check for any errors in the ‘console’ window and fix them, repeatedly running the code again until you’ve corrected all the errors.

You should see a block of bricks now, as shown above. You may have to turn the player around in the Minecraft world before you can see your house.

Adding the floor and door

Now, let’s make our house a bit more interesting! Add the lines for the floor and door. Note that the floor extends beyond the boundary of the wall of the house; can you see how we achieve this?

Hint: look closely at how we calculate the x and z attributes as compared to when we created the house shell above. Also note that we use a value of y-1 to create the floor below our feet.

Minecraft doors are two blocks high, so we have to create them in two parts. This is where we have to use the data argument. A value of 0 is used for the lower half of the door, and a value of 8 is used for the upper half (the part with the windows in it). These values will create an open door. If we add 4 to each of these values, a closed door will be created.

Before you run your program again, move to a new location in Minecraft to build the house away from the previous one. Then run it to check that the floor and door are created; you will need to fix any errors again. Even if your program runs without errors, check that the floor and door are positioned correctly. If they aren’t, then you will need to check the arguments so setBlock and setBlocks are exactly as shown in the listing.

Adding windows

Hopefully you will agree that your house is beginning to take shape! Now let’s add some windows. Looking at the plan for our house, we can see that there is a window on each side; see if you can follow along. Add the four lines of code, one for each window.

Now you can move to yet another location and run the program again; you should have a window on each side of the house. Our house is starting to look pretty good!

Adding a roof

The final stage is to add a roof to the house. To do this we are going to use wooden stairs. We will do this inside a loop so that if you change the width of your house, more layers are added to the roof. Enter the rest of the code. Be careful with the indentation: I recommend using spaces and avoiding the use of tabs. After the if statement, you need to indent the code even further. Each indentation level needs four spaces, so below the line with if on it, you will need eight spaces.

Since some of these code lines are lengthy and indented a lot, you may well find that the text wraps around as you reach the right-hand side of your editor window — don’t worry about this. You will have to be careful to get those indents right, however.

Now move somewhere new in your world and run the complete program. Iron out any last bugs, then admire your house! Does it look how you expect? Can you make it better?

Customising your house

Now you can start to customise your house. It is a good idea to use Save As in the menu to save a new version of your program. Then you can keep different designs, or refer back to your previous program if you get to a point where you don’t understand why your new one doesn’t work.

Consider these changes:

  • Change the size of your house. Are you able also to move the door and windows so they stay in proportion?
  • Change the materials used for the house. An ice house placed in an area of snow would look really cool!
  • Add a back door to your house. Or make the front door a double-width door!

We hope that you have enjoyed writing this program to build a house. Now you can easily add a house to your Minecraft world whenever you want to by simply running this program.

Get the complete code for this project here.

Continue your Minecraft journey

Minecraft Pi’s programmable interface is an ideal platform for learning Python. If you’d like to try more of our free tutorials, check out:

You may also enjoy Martin O’Hanlon’s and David Whale’s Adventures in Minecraft, and the Hacking and Making in Minecraft MagPi Essentials guide, which you can download for free or buy in print here.

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More power to your Pi

It’s been just over three weeks since we launched the new Raspberry Pi 3 Model B+. Although the product is branded Raspberry Pi 3B+ and not Raspberry Pi 4, a serious amount of engineering was involved in creating it. The wireless networking, USB/Ethernet hub, on-board power supplies, and BCM2837 chip were all upgraded: together these represent almost all the circuitry on the board! Today, I’d like to tell you about the work that has gone into creating a custom power supply chip for our newest computer.

Raspberry Pi 3 Model B+, with custome power supply chip

The new Raspberry Pi 3B+, sporting a new, custom power supply chip (bottom left-hand corner)

Successful launch

The Raspberry Pi 3B+ has been well received, and we’ve enjoyed hearing feedback from the community as well as reading the various reviews and articles highlighting the solid improvements in wireless networking, Ethernet, CPU, and thermal performance of the new board. Gareth Halfacree’s post here has some particularly nice graphs showing the increased performance as well as how the Pi 3B+ keeps cool under load due to the new CPU package that incorporates a metal heat spreader. The Raspberry Pi production lines at the Sony UK Technology Centre are running at full speed, and it seems most people who want to get hold of the new board are able to find one in stock.

Powering your Pi

One of the most critical but often under-appreciated elements of any electronic product, particularly one such as Raspberry Pi with lots of complex on-board silicon (processor, networking, high-speed memory), is the power supply. In fact, the Raspberry Pi 3B+ has no fewer than six different voltage rails: two at 3.3V — one special ‘quiet’ one for audio, and one for everything else; 1.8V; 1.2V for the LPDDR2 memory; and 1.2V nominal for the CPU core. Note that the CPU voltage is actually raised and lowered on the fly as the speed of the CPU is increased and decreased depending on how hard the it is working. The sixth rail is 5V, which is the master supply that all the others are created from, and the output voltage for the four downstream USB ports; this is what the mains power adaptor is supplying through the micro USB power connector.

Power supply primer

There are two common classes of power supply circuits: linear regulators and switching regulators. Linear regulators work by creating a lower, regulated voltage from a higher one. In simple terms, they monitor the output voltage against an internally generated reference and continually change their own resistance to keep the output voltage constant. Switching regulators work in a different way: they ‘pump’ energy by first storing the energy coming from the source supply in a reactive component (usually an inductor, sometimes a capacitor) and then releasing it to the regulated output supply. The switches in switching regulators effect this energy transfer by first connecting the inductor (or capacitor) to store the source energy, and then switching the circuit so the energy is released to its destination.

Linear regulators produce smoother, less noisy output voltages, but they can only convert to a lower voltage, and have to dissipate energy to do so. The higher the output current and the voltage difference across them is, the more energy is lost as heat. On the other hand, switching supplies can, depending on their design, convert any voltage to any other voltage and can be much more efficient (efficiencies of 90% and above are not uncommon). However, they are more complex and generate noisier output voltages.

Designers use both types of regulators depending on the needs of the downstream circuit: for low-voltage drops, low current, or low noise, linear regulators are usually the right choice, while switching regulators are used for higher power or when efficiency of conversion is required. One of the simplest switch-mode power supply circuits is the buck converter, used to create a lower voltage from a higher one, and this is what we use on the Pi.

A history lesson

The BCM2835 processor chip (found on the original Raspberry Pi Model B and B+, as well as on the Zero products) has on-chip power supplies: one switch-mode regulator for the core voltage, as well as a linear one for the LPDDR2 memory supply. This meant that in addition to 5V, we only had to provide 3.3V and 1.8V on the board, which was relatively simple to do using cheap, off-the-shelf parts.

The Pi Zero sports a BCM2835 processor, which only needs two external switchers (the components clustered behind the camera port)

When we moved to the BCM2836 for Raspberry Pi Model 2 (and subsequently to the BCM2837A1 and B0 for Raspberry Pi 3B and 3B+), the core supply and the on-chip LPDDR2 memory supply were not up to the job of supplying the extra processor cores and larger memory, so we removed them. (We also used the recovered chip area to help fit in the new quad-core ARM processors.) The upshot of this was that we had to supply these power rails externally for the Raspberry Pi 2 and models thereafter. Moreover, we also had to provide circuitry to sequence them correctly in order to control exactly when they power up compared to the other supplies on the board.

Power supply design is tricky (but critical)

Raspberry Pi boards take in 5V from the micro USB socket and have to generate the other required supplies from this. When 5V is first connected, each of these other supplies must ‘start up’, meaning go from ‘off’, or 0V, to their correct voltage in some short period of time. The order of the supplies starting up is often important: commonly, there are structures inside a chip that form diodes between supply rails, and bringing supplies up in the wrong order can sometimes ‘turn on’ these diodes, causing them to conduct, with undesirable consequences. Silicon chips come with a data sheet specifying what supplies (voltages and currents) are needed and whether they need to be low-noise, in what order they must power up (and in some cases down), and sometimes even the rate at which the voltages must power up and down.

A Pi 2. Power supply components are clustered in the bottom left-hand corner next to the micro USB port, middle (above the LPDDR2 chip, which is on the bottom of the PCB) and above the A/V jack.

In designing the power chain for the Pi 2 and 3, the sequencing was fairly straightforward: power rails power up in order of voltage (5V, 3.3V, 1.8V, 1.2V). However, the supplies were all generated with individual, discrete devices. Therefore, I spent quite a lot of time designing circuitry to control the sequencing — even with some design tricks to reduce component count, quite a few sequencing components are required. More complex systems generally use a Power Management Integrated Circuit (PMIC) with multiple supplies on a single chip, and many different PMIC variants are made by various manufacturers. Since Raspberry Pi 2 days, I was looking for a suitable PMIC to simplify the Pi design, but invariably (and somewhat counter-intuitively) these were always too expensive compared to my discrete solution, usually because they came with more features than needed.

One device to rule them all

It was way back in May 2015 when I first chatted to Peter Coyle of Exar (Exar were bought by MaxLinear in 2017) about power supply products for Raspberry Pi. We didn’t find a product match then, but in June 2016 Peter, along with Tuomas Hollman and Trevor Latham, visited to pitch the possibility of building a custom power management solution for us.

I was initially sceptical that it could be made cheap enough. However, our discussion indicated that if we could tailor the solution to just what we needed, it could be cost-effective. Over the coming weeks and months, we honed a specification we agreed on from the initial sketches we’d made, and Exar thought they could build it for us at the target price.

The chip we designed would contain all the key supplies required for the Pi on one small device in a cheap QFN package, and it would also perform the required sequencing and voltage monitoring. Moreover, the chip would be flexible to allow adjustment of supply voltages from their default values via I2C; the largest supply would be capable of being adjusted quickly to perform the dynamic core voltage changes needed in order to reduce voltage to the processor when it is idling (to save power), and to boost voltage to the processor when running at maximum speed (1.4 GHz). The supplies on the chip would all be generously specified and could deliver significantly more power than those used on the Raspberry Pi 3. All in all, the chip would contain four switch-mode converters and one low-current linear regulator, this last one being low-noise for the audio circuitry.

The MXL7704 chip

The project was a great success: MaxLinear delivered working samples of first silicon at the end of May 2017 (almost exactly a year after we had kicked off the project), and followed through with production quantities in December 2017 in time for the Raspberry Pi 3B+ production ramp.

The team behind the power supply chip on the Raspberry Pi 3 Model B+ (group of six men, two of whom are holding Raspberry Pi boards)

Front row: Roger with the very first Pi 3B+ prototypes and James with a MXL7704 development board hacked to power a Pi 3. Back row left to right: Will Torgerson, Trevor Latham, Peter Coyle, Tuomas Hollman.

The MXL7704 device has been key to reducing Pi board complexity and therefore overall bill of materials cost. Furthermore, by being able to deliver more power when needed, it has also been essential to increasing the speed of the (newly packaged) BCM2837B0 processor on the 3B+ to 1.4GHz. The result is improvements to both the continuous output current to the CPU (from 3A to 4A) and to the transient performance (i.e. the chip has helped to reduce the ‘transient response’, which is the change in supply voltage due to a sudden current spike that occurs when the processor suddenly demands a large current in a few nanoseconds, as modern CPUs tend to do).

With the MXL7704, the power supply circuitry on the 3B+ is now a lot simpler than the Pi 3B design. This new supply also provides the LPDDR2 memory voltage directly from a switching regulator rather than using linear regulators like the Pi 3, thereby improving energy efficiency. This helps to somewhat offset the extra power that the faster Ethernet, wireless networking, and processor consume. A pleasing side effect of using the new chip is the symmetric board layout of the regulators — it’s easy to see the four switch-mode supplies, given away by four similar-looking blobs (three grey and one brownish), which are the inductors.

Close-up of the power supply chip on the Raspberry Pi 3 Model B+

The Pi 3B+ PMIC MXL7704 — pleasingly symmetric

Kudos

It takes a lot of effort to design a new chip from scratch and get it all the way through to production — we are very grateful to the team at MaxLinear for their hard work, dedication, and enthusiasm. We’re also proud to have created something that will not only power Raspberry Pis, but will also be useful for other product designs: it turns out when you have a low-cost and flexible device, it can be used for many things — something we’re fairly familiar with here at Raspberry Pi! For the curious, the product page (including the data sheet) for the MXL7704 chip is here. Particular thanks go to Peter Coyle, Tuomas Hollman, and Trevor Latham, and also to Jon Cronk, who has been our contact in the US and has had to get up early to attend all our conference calls!

The MXL7704 design team celebrating on Pi Day — it takes a lot of people to design a chip!

I hope you liked reading about some of the effort that has gone into creating the new Pi. It’s nice to finally have a chance to tell people about some of the (increasingly complex) technical work that makes building a $35 computer possible — we’re very pleased with the Raspberry Pi 3B+, and we hope you enjoy using it as much as we’ve enjoyed creating it!

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