Tabla de contenidos para Complete Raspberry Pi en Complete Raspberry Pi

Everything you need to master the Raspberry Pi The Raspberry Pi has amazed and astounded the world with its diminutive dimensions and powerhouse performance. It’s been used for all sorts of great projects and collaborations and has been utilised in living rooms, nature reserves, the oceans of the world and even in outer space. It really is an incredible little computer. We’ve put together dozens of tutorials, complete with step-by-step pictures, that are easy to follow, to help you get to grips with your Raspberry Pi. We tell you exactly what to do, how to do it and where to go to learn more. There’s plenty here to help you become a Raspberry Pi expert and start your own unique and equally amazing project. There’s never been a better time…

40 GPIO Pins The GPIO (General Purpose Input Output) pins can be accessed directly on the Raspberry Pi. These are used in projects to connect the Raspberry Pi to electronic circuits and control electric devices. Some can be turned on and off while the Raspberry Pi is running. ARM-Powered At the heart of the Raspberry Pi 3 is a Broadcom BCM2837 System on Chip (SoC). It contains a powerful 1.2GHz 64-bit quad-core ARM Cortex-A53 CPU. This is 50-60 percent faster than the Raspberry Pi 2 and ten times as fast as the original Raspberry Pi. DSI The Display Interface (DSI) can be used to connect a display directly to the Raspberry Pi board. SD Card Slot Instead of a hard drive you use an SD Card with the Raspberry Pi.…

GETTING TO KNOW NOOBS The easiest way to get up and running is to use NOOBS, a software program created by the Raspberry Pi Foundation. You can buy a NOOBS SD Card from Raspberry Pi but it’s easy to make your own with an old unused SD Card (8GB recommended). STEP 1 You’re going to use a utility called SD Card Formatter 4 to erase the SD Card with correct formatting. You can download this app from https://www.sdcard.org/downloads/formatter_4/. Click Download SD Formatter for Mac and Accept. Click the SDFormatter.pkg file in your Downloads folder and follow the instructions to install the app. STEP 2 You’re going to use a 8GB SD Card to install the operating system on our Raspberry Pi. The card needs to be formatted, which will erase…

USING NOOBS In this feature we will download the NOOBS (New out Of Box) software from the Raspberry Pi website. This software is then copied to the SD Card, which is inserted into a Raspberry Pi. NOOBS enables you to choose which OS you want to use when you first start the Raspberry Pi. STEP 1 You can download the latest version of NOOBS from the Raspberry Pi website. Open a web browser and enter www.raspberrypi.org/downloads into the URL field. Click Download ZIP and choose Save File and click OK. The file will be saved to your Downloads STEP 2 You’re going to extract the files from the NOOBS zip file directly to the SD Card. Remove and insert the SD Card to make sure it is mounted, so you…

ACCESSING THE CONFIG.TXT FILE This file is normally accessible as /boot/config.txt from Linux and must be edited as root but from Windows or macOS, it is seen as a file in the only accessible part of the card (once you insert the card into your computer). If you need to apply some of the configuration settings shown here but you don’t have a config.txt on your boot partition yet, then simply create it as a new text file. Any changes you make to the file will be applied after you reboot your Raspberry Pi. When editing or creating your config.txt file it is important to follow the simple text format. The format is a single property=value entry on each line, where value is either a string or integer. In the…

USING TERMINAL Despite its graphical PIXEL interface, Raspbian is a Linux operating system and this means you’ll spend a lot of time working with text commands. Far more than you would on a Mac or Windows computer. Using the command line is an important part of learning to use a Raspberry Pi computer. STEP 1 By default the Raspberry Pi boots directly into the PIXEL interface. Here you use a visual metaphor, files, buttons and so on, to make changes to your computer. The command line is where you control a computer by entering text commands. Click Terminal in the Menu bar to view the console. STEP 2 You can enter commands into the Terminal to make changes to the computer. This works alongside the PIXEL interface. Enter mkdir Desktop/testfolder…

WHY USE VNC? The Raspberry Pi is easy to set up and use in projects around the home. But many of these projects don’t need a screen. Some, like Internet doorbells would be silly with a screen attached. VNC lets you control one Raspberry Pi from another. STEP 1 Setting up VNC used to require entering several commands in Terminal. With PIXEL you can just head into the Raspberry Pi Configuration tool: Menu > Preferences > Raspberry Pi Configuration. Click Interfaces and choose Enable next to VNC. Click OK. STEP 2 A new icon, marked “VNC”, appears in the top right in the Menu bar. Click it to reveal the VNC Server window. Here you’ll see a section marked “Ready for connections” and beneath it a section “Get Started”. Click…

VIEWING AND MOVING FILES You can move, manage and delete files using the Command Line but like all modern operating systems Raspbian has a program to help you manage your files. Discover how to use the File Manager app. STEP 1 Raspbian includes a great file management program called “File Manager PCManFM” or just “File Manager” for short. Click on the FileManager PCManFM icon in the Launch Bar or choose Menu > Accessories > File Manager. STEP 2 File Manager displays the folders in your Home folder (this should match your user name, ‘Pi’ by default). By default you should have Desktop, Documents, Downloads, Music, Picutres, Public, python_games, Scratch and folders. Double-click any folder to open it and view its contents. Click the Parent Folder icon or press Alt-Up Arrow…

MANAGE PROCESSES The Raspbian operating system is made up of lots of processes, known as “commands”. These can all be viewed, managed and forced to quit using the Task Manager program. STEP 1 The Task Manager app is a great way to get an overview of all the different processes that make up your Raspbian operating system. Choose Menu > Accessories > Task Manager to open the Task Manager app. At the top you will see how much CPU and Memory is being currently used by your system. STEP 2 All the processes are listed in the Command column. Next to this is the User that owns the process. Next is the percentage of CPU that it is currently taking up; note that it is possible for processes to take…

JUST LIKE MICROSOFT OFFICE Leafpad and Nano are great for editing text files but if you want to create a more complex document on your Raspberry Pi then LibreOffice is the app to use. It’s just like having Microsoft Office on your Raspberry Pi. STEP 1 LibreOffice is included with Raspberry Pi and PIXEL so there is no need to install it. Click on Menu > Office. Inside you will find five apps: Base, Calc, Draw, Impress and Writer. These are functionally similar to Microsoft Office apps. Base is a database program, Impress is presentation software like PowerPoint; Calc is Excel and Writer is similar to Microsoft Word. STEP 2 Choose Menu > Office > LibreOffice Writer to open the word processing application. You can instantly tell that this is…

UNDERSTANDING UNIX Unix is a family of operating systems; one of which is Linux: the system that underlies the Raspbian OS. Because Linux is a Unix-like system, you can use Unix commands to control it. This is the Linux Command Line, and learning how to use it is vital to controlling a Raspberry Pi. STEP 1 You can enter Unix commands into the Terminal app inside the LXDE desktop, as you have done throughout this book. For this Unix section you will work completely in the command line though. You can quit the desktop by entering pkill x into the terminal. The desktop will close down leaving you back in the command line. STEP 2 It’s important to get some terms cleared up. Unix is hard to define. Originally Unix…

LOOKING AT FILES Computer operating systems are files and directories. While you might be used to seeing your own files, the average modern OS keeps other files out of sight. In Raspbian you get access to every file on your system, so learn how to manage files wisely. STEP 1 We’ve already looked at “ls”, which lists the files in the working directory, but you are more likely to use a command like “ls –l”. The bit after the command (the ‘-lah’) is known as the argument. This is an option that modifies the behaviour of the command. STEP 2 The “-l” argument lists files and directories in long format. Each file and directory is now on a single line, and before each file is a lot of text. First…

USING THE MOVE COMMAND Knowing how to move files is an essential part of learning Unix. Once you know how to move files and directories around you can start to organise your Raspberry Pi and place items where they are required. STEP 1 Before we can move anything around, we need to have a few test items in our home directory. Enter touch testfile and mkdir testdir to create a test file and test directory in your home directory. Enter ls to check that they are both present. STEP 2 Files and directories are moved using the “mv” command. This is different to commands we’ve looked at so far because it has two arguments (remember Unix command line is command, option, argument). The first argument is source (the file or…

WHAT IS A USER? An important part of using Unix is the concept of users and understanding which user you are, and which group you belong to. Like all modern computers, you can have multiple user accounts, and each has different types of access. STEP 1 The first thing you need to do is get a concept of which user you are. Enter whoami into the command line and press return. It should say “pi” (unless you set up your account name differently during setup). The “whoami” command might seem a bit simplistic, but it comes in very handy sometimes. STEP 2 There are times when you’ll be doing something in Unix and get an error with “Permission denied”; typically when you try to create, edit or execute (run) a…

The Raspberry Pi is the powerhouse for many projects but one in particular stands head and shoulders above the rest, the FUZE Project. The FUZE is a learning environment for the Raspberry Pi that’s used in schools across the UK. It combines imagination, engineering and education in a cleverly designed retro-themed keyboard case. We’ll look at the models available and how to get up and running with the FUZE. The FUZE comes with its own programming language, FUZE BASIC. This allows you to create simple routines, games, complex algorithms and even interact with robots and other electronics. We’ll also look at the popular Scratch high-level programming language, and dig a little into the latest version of Python.…

BACK TO BASICS Let’s begin our programming journey with FUZE BASIC, an environment where you can create anything, from simple scripts to complex games with graphics and sounds. STEP 1 in the bottom right panel, the one that’s coloured white on a red background? Click it and you launch the FUZE BASIC, complete with a C64-style retro interface. You can also double-click the FUZE BASIC V3 icon on the desktop. STEP 2 Don’t worry if you don’t have a FUZE Workstation. FUZE BASIC is available for Windows, the BBC micro:bit and the Raspberry Pi (since it’s already running on a RPi). Open a browser to www.fuze.co.uk/download-fuze.html and follow the download instructions for FUZE BASIC for Windows and the step-by-step instructions to install it on a Raspberry Pi. STEP 3 The…

I, ROBOT We won’t go into the construction of the robot arm here, the instructions which come with the arm are easy to follow and it can be completed and ready for use within a couple of hours or so. Let’s look at how to get it working. STEP 1 The robot arm is one of the first external hardware components that was released and fully compatible with the Raspberry Pi; as such, it’s an excellent project to get into, from the construction of the arm itself, to operating it via the FUZE Workstation. STEP 2 Start by plugging the robot arm into one of the spare USB ports on the back of the FUZE workstation. Ensure that the arm has its batteries correctly in place and that its power…

Scratch is a powerful introduction to programming created by MIT (Massachusetts Institute of Technology). It’s an extremely high-level programming language designed to teach children the building blocks of programming. It’s highly visual with graphical characters known as sprites, backdrops and sound effects. These can be programmed in advanced or set to respond to user input. This makes it easy to create games and other visual projects. Block Palette The commands are known as “blocks” and sit on the left in the Block Palette. The tabs at the top enable you to choose different categories such as Motion and Sensing. Script Area Blocks are dragged from the Block Palette to the Script Area to form a script (or program). The blocks snap to each other to form a vertical column, which…

INTERACTIVE CONTROL The only Control option you’ve looked at so far is the when [flag] clicked block, which starts the program. Once your program is running it does its thing, right up until it finishes. You’re going to use the other Control blocks to do something more interesting. STEP 1 Open the Dancing_Cat program from previous tutorials. Select Sprite1 and click on Scripts so you can see the when [flag] clicked script. Now click Control in the Block Palette and drag the when [space] key pressed block to an empty part of the Script Area. STEP 2 You can drag and rearrange the block scripts to any part of the Script Area. We like to have our when [flag] clicked script in the top left but it really doesn’t matter…

WHAT IS A VARIABLE? Variables, sometimes called “vars” for short, can be many different things. The two most common types are words (called strings) such as a player’s name; or numbers (called integers) such as a score or health. STEP 1 You’re going to leave the disco behind. Choose File > New (click Yes if you have a project that needs saving). You’ll start with a blank stage containing a single Scratch Cat sprite. Click Control and drag a when flag clicked block to the Script Area. STEP 2 You’re going to create a simple game where Scratch Cat rolls two dice and wins if they’re both the same number. Click Variables. Unlike other sections there are no blocks here, instead you have to create the variables you need. You…

VARIOUS VARIABLES We’ll be working with the Python 3 IDLE Shell in this tutorial. If you haven’t already, close down the Terminal from the last tutorial, and open Menu > Programming > Python 3 (IDLE). STEP 1 In BASIC you were required to use a dollar sign to denote a string, which is a variable made up of multiple characters, such as the name of a person. In Python this isn’t necessary; for example, in the Shell enter: name=”David Hayward” or use your own name, unless you’re also called David Hayward. STEP 2 You can check the type of variable in use by issuing the type () command, placing the name of the variable inside the brackets. In our example, this would be: type (name). Add a new string variable:…

GOING GRAPHICAL You can draw simple graphics, lines, squares and so on or you can use one of the many Python modules available, to bring out some spectacular effects. STEP 1 One of the best modules to begin learning Python graphics is Turtle. The Turtle module is, as the name suggests, based on the turtle robots used in many schools that can be programmed to draw something on a large piece of paper on the floor. The Turtle module can be imported with: import turtle. STEP 2 Let’s begin by drawing a simple circle. Start a New File, then enter the following code: import turtle turtle.circle(50) turtle.getscreen()._root.mainloop() Pressing F5 saves the code and executes it as usual. You now have a new window open up and the ‘Turtle’ will draw…

KODI CAN DO The software used to turn your Raspberry Pi into a media centre is called Kodi, although some people call it XMBC (who develop the software). It’s open-source, so there are lots of customised versions available. STEP 1 The easiest way to set up and use Kodi on your Raspberry Pi is to use NOOBS and install the LibreELEC option. You’ll need to connect your Raspberry Pi to the Internet so it can download additional files for the installation. Follow the NOOBs tutorial to install NOOBS but choose LibreELEC RPi2 and click Install. STEP 2 When the Raspberry Pi starts up, you will see a Welcome screen. Ensure the Regional Settings are set to English (or choose your preferred language) and click Next. By default the device will…

CAMJAM The Cambridge Raspberry Jam (camjam.me) teaches children of all ages how to build electronics projects and the kits are sold to everyone via the Pi Hut. The CamJam EduKit #3 has everything you need to build a robot (thepihut.com/collections/camjam-edukit). STEP 1 The CamJam EduKit 3 includes wheels, motors, a battery box, an EduKit Controller Board and two sensors. You also get a breadboard, wires and resistors to bring it all together, along with some double-sided tape. We suggest you get a USB battery charger, the type used to recharge phones, and a Wi-Fi dongle. STEP 2 You’ll need a chassis for your robot. We’re using a tin box (the type you often get to keep knick-knacks in). You can use any flat surface as a chassis, so long as…

TOY CONTROL This Spy Rover project turns an old remote control toy into a surveillance robot with the Raspberry Pi providing the brains. It’s a great way to get to grips with robotics and network communication. STEP 1 We start with a Big Bargain King Force Excavator toy, although you can use any similar remote control device for the project. Our digger with tracks is ideal for robotics as it has simple controls and a track mechanism. STEP 2 Stratos removed the top half of the robot so he just had the tracks to work with. The flat surface on the top of the robot provides a base for the rest of the components. The heart of the operation is a Raspberry Pi 1 Model B. STEP 3 The Raspberry…

SETTING UP A HAT You shouldn’t have any trouble setting up a Rasbperry Pi HAT. The hardware is designed to work as soon as you connect it to the GPIO pins. But from then you’ll have a whole range of new hardware options available; check the documentation on each maker’s website. PRICE: £23 / €25.99 More info: raspberrypi.org/products/sense-hat/ SENSE HAT The first HAT you should got out an buy is this one, the SENSE HAT. This board was developed as part of the Astro Pi project, and was used by Tim Peake aboard the International Space Station (ISS). It features an 8x8 RGB LED display, joystick, gyroscope, accelerometer and magnetometer. It’s also got a bunch of sensors to measure pressure, humidity, depth and altitude. So you get a lot for…

THE RASPBERRY PI SOFTWARE KIT The software mentioned here is probably the bare minimum you will need to get the most from your Raspberry Pi. Specialised software might be needed for more specialised projects. GPARTED Gparted (GNOME Partition Editor) is a an official GNOME partition editing application alongside Disks. GParted is used for creating, deleting, resizing, moving, checking and copying disk partitions and their file systems. This is useful for creating space for new operating systems, reorganising disk usage, copying data residing on hard disks and mirroring one partition with another (disk imaging). WIN32 DISKIMAGER This program is designed to write a raw disk image to a removable device; or backup a removable device to a raw image file. It is very useful for embedded development, namely Arm development projects…

Using the Raspberry Pi should always start with understanding the hardware. There are several versions of the Raspberry Pi available: Pi 1 Model A+, Pi 1 Model B+, Pi 2 Model B, Pi 3 and Pi Zero. Confused? You needn’t be. The Raspberry Pi may be diminutive in size but it’s a surprisingly powerful computer. This little powerhouse is capable of so much but first we need to make sure we have everything needed to get up and running. Throughout this section we help you figure out what’s needed in terms of connectivity, the extra hardware and of course the operating system itself. From there we look at getting the Raspberry Pi set up and ready to use, regardless of whether you’re working with a Windows PC or Apple Mac.…

FASTER AND CONNECTED The new Raspberry Pi board has a faster processor, making it more like a regular desktop computer. It also packs better connectivity features. STEP 1 If you’re familiar with the Raspberry Pi, you’ll notice that the Raspberry Pi looks a lot like the Raspberry Pi 2. It has the same board, with the components laid out in the same place. This design is handy because all the hardware designed for the Raspberry Pi 2 will work with the new board. STEP 2 Faster CPU. The marquee feature for the Raspberry Pi 3 is a new BCM2837 System on Chip (SoC). This system contains a custom hardened 1.2GHz 64-bit quad-core ARM Cortex-A53 CPU to the Raspberry Pi, which is 50-60 percent faster than the Raspberry Pi 2 and…

SETTING UP WITH NOOBS NOOBS (New Out Of Box Software) is a program used to make setting up a Raspberry Pi simple. You can buy SD Cards with NOOBS preinstalled, but here we’ll look at how to format your SD Card and install NOOBS using a Windows computer. STEP 1 You’re going to use a utility called SD Card Formatter 4 to erase the SD Card with correct formatting. You can download this app from https://www.sdcard.org/downloads/formatter_4/. Click Download SD Formatter for Windows and click Accept and Open. Double-click Setup and choose Run then follow the Install instructions. STEP 2 You’re going to use a 8GB SD Card to install the operating system on our Raspberry Pi. The card needs to be formatted which will erase all the data on it,…

SET UP YOUR OPERATING SYSTEM NOOBS (New Out Of Box Software) is the standard way to set up an operating system and start using your Raspberry Pi. In previous tutorials we’ve shown you how to install NOOBS onto an SD Card; now it’s time to use NOOBS to set up your Raspberry Pi. STEP 1 Insert the SD Card containing NOOBS software into your Raspberry Pi and connect the cables, including the HDMI cable and a keyboard and mouse. Finally insert the Micros USB cable connected to the power adaptor to start up the Raspberry Pi. You should be greeted with this screen. STEP 2 A whole bunch of different operating systems are available but you need to have your Raspberry Pi connected to a network to download them. For…

The official operating system for the Raspberry Pi, Raspbian OS, has a fantastic collection of built-in programs and apps to help you get the most from your Pi. Out of the box, the Raspberry Pi is a fully functional desktop computer, complete with a Microsoft Office compatible word processor, spreadsheet program, DTP and more. In this section, discover how to get the Pi online and ensure it’s connected with a unique IP address to your home network. We even show you how to connect to the Raspberry Pi desktop remotely from another computer, whether Windows or macOS. One of the specialties of the Pi is that it’s not limited to the programs and apps that come with the operating system. With a few commands, you can download and install thousands…

USING FTP FTP (File Transfer Protocol) is a technique often used to send files from one computer to another. Most people encounter FTP when they need to upload and download files to and from the Internet, but FTP is great for sending files from your computer to your Raspberry Pi. STEP 1 Before you get started you’ll need to download an FTP client (a program used to make a connection and transfer files). It doesn’t matter which FTP client you use but our recommendation is FileZilla. On your computer (not your Raspberry Pi) visit https://filezilla-project.org/ and click Download Filezilla Client. STEP 2 You need to know the IP (Internet Protocol) address that your Raspberry Pi is using to connect to your local network. Open a terminal window and click Terminal…

CUSTOM TERMINAL You’ll spend a lot of time in Terminal, so why not get to know it a bit better and set it up to work just the way you want. STEP 1 Start Terminal by clicking the Terminal icon in the Application Launch Bar. You can also start Terminal by pressing Control-Alt-T or choosing Menu > Accessories > Terminal. Terminal emulates the old style video terminals from before desktop interfaces; so by default it displays bright (mostly green) on a black background. STEP 2 The first thing most people overlook is the ability to run multiple terminals at once in different tabs. Choose File > New Tab (Shift-Control-T) to create a new tab. Navigating multiple directories simultaneously can be a challenge in Terminal and tabs makes it that much…

GET TO KNOW GIMP Your Raspberry Pi can display images with its built-in Image View app but for any image editing you’ll need GIMP (GNU Image Manipulation Progarm). GIMP is a powerful software package for photo editing and is a great tool to install on your Raspberry Pi. STEP 1 Open terminal and enter sudo apt install gimp to download and install the GIMP package. An alert will appear saying: “after this operation, 117 MB of additional disk space will be used. Do you want to continue [Y/n]?” Enter y and press Return. GIMP will now be installed in Raspbian. GIMP is a lot larger than most programs you’ll install, so the installation takes longer. STEP 2 When the installation has completed you will find GIMP under Menu > Graphics…

Owner Each file has an owner, typically the person who created the file. You’ll usually have two owners: pi and root. Pi is for files and directories created by your default user account, and root is for all the system files. Permissions At the start of each item in our list is a list of letters and hyphens. These represent the permissions for each file, and who can read, write (edit) and execute (run) the file. It look complex but we’ll explain how to understand and edit permissions in simple steps. Running Commands Unix has a wide range of commands and tools built into it. You can manage your entire Raspberry Pi from the command line. The desktop environment is, in many ways, just a skin over the top of…

CREATING FILES Once you learn to recognise the files and directories that make up Raspbian OS, it’s time to discover how to make your own. Knowing how to make, edit and delete files and directories is essential if you want to make your own projects. STEP 1 We’re going to create a file using a command called Touch. Touch is an interesting command that reaches out to a file, or directory, and updates it (this changes the system time as if you’d just opened the file). You can see Touch in access using “ls –l” and checking the time next to a directory (such as Scratch). STEP 2 Now enter touch Scratch and ls –l again and notice that the time has changed. It now matches the current time. You…

OWNER AND PRIVILEGE An important part of using Unix is the concept of users and who owns files, and who has privilege rights. Like all modern computers you can have multiple user accounts, and each has different types of access. You need to know this information to manage files. STEP 1 If you followed the previous tutorial you should now have two accounts on your Rasbperry Pi. One called “pi” and the other with a name (lucy in our case). An essential aspect of Unix is the idea of file and directory ownership; who owns, and has access to what. We need a test file; enter touch testfile. STEP 2 Now enter ls –l and let’s have a good look at the default permissions file. Our testfile.txt files starts with…

INPUT AND OUTPUT Everything on a computer is about input and output. You input things into the computer (press keys, move the mouse) and it makes calculations and outputs things (changes the display, makes a noise, for example). In Linux you really get to learn about it. STEP 1 When you enter commands into Linux (in the command line), you are using standard input and output. This is so obvious that most people don’t even think about it. You enter commands using the keyboard (that’s input) and it responds to the screen (output). This is the regular way of doing it, which is why it’s “standard input and output” (often called “stdin” and “stdout” for short). STEP 2 As far as the computer is concerned, input and output can be…

The FUZE Workstation itself, styled on a BBC Micro Model B from the ‘80s, constructed with a metal body and high quality keyboard complete with programmable red coloured F-keys. Note the holes at the top edges: these are compatible with many popular plastic building blocks and electronic construction kits. The Rear IO back plate is where you plug in your power, connection to a monitor, mouse, SD card, audio and any USB devices you want to include. From left to right, across the backplate, there’s an on/off switch, a power port, a bank of four USB ports, the Ethernet port, SD card slot and HDMI port. You can remove the four corner screws of the backplate to gain access to the Raspberry Pi, USB hub and cables inside the workstation…

LET THERE BE VARIABLES We’ve already looked at assigning some variables in the previous tutorial so let’s extend that and see what else we can do with them. STEP 1 Enter the Program Editor, by pressing the F2 key. Within the Program Editor enter the following, pressing Enter after each line: Let x=10 Print x Now click on the Save button, along the top of the screen and save the program as ‘Variables1’. Click the OK button to return to the Editor and the Run button to execute the code. STEP 2 After clicking Run you drop back into Immediate Mode and the display will output the number 10. To break down this simple code, you’ve created the variable called X, and you’ve allocated the value 10 to it. The…

GPIO The Raspberry Pi enables you to access electronic pins, known as GPIO (General Purpose Input and Output). These are used to interact with external electronics like LED lights and switches. To start with you’ll learn to build circuits using a tool known as a Breadboard. STEP 1 The FUZE Workstation comes with a breadboard and some basic electronics components -you can follow along with this tutorial by getting a breadboard, 1 x blue and 1 x red breadboard wires, a 5mm LED, a 22Ohms 5% resistor, 9V battery, and a 9V snap battery clip. Your local electronics shop will help you out. STEP 2 Get out the breadboard, hold it up vertically and take a good look at it. You should see four vertical columns. The two pairs, on…

CODE REPOSITORY From fractal generators to encryption programs and animation, here are ten excellent examples of what others have done with a little patience and a lot of code. EXAMPLE 1 James Cook’s Tree of Pythagoras is an impressive fractal, constructed from squares, that looks remarkably complex but takes up surprisingly little code. You can find it at www.fuze.co.uk/code-repository; just enter the code and Run it to be amazed. EXAMPLE 2 Simon Plouffe is a Mathematician who, back in the ‘70s, created some incredible cardiod images by dividing a circle into prime parts and drawing lines based on mathematical spaced points on the circumference. Anyway, enter this and be amazed: EXAMPLE 3 This code will load any image and make it scroll across the screen from right to left. Put…

INSTALLING SCRATCH Scratch is built into Raspbian with PIXEL and is installed by default, so you just start it up and you’re good to go. You may need to update it later on, to use electronic attachments like breadboards, but more on that later. For now follow the steps to get started. STEP 1 Scratch runs from the PIXEL interface so enter startx if you’re in the command line. Now choose Menu > Programming > Scratch. The program opens in a new window, click the Maximise button on the right so you have plenty of space to view the window and all its contents. STEP 2 You see the Scratch interface with a list of blue items in the Block Palette left, an empty Script Area and a stage. On…

LOOK SPRITE Sprites are 2D (flat) graphics drawn on top of a background. They are commonly used to display information in games such as health bars, scores or lives. Older games are composed entirely of sprites, just like our Scratch project. STEP 1 You’re going to add another sprite to our project and a second character to the scene. One fun and quick way to do this is to click the Get surprise sprite icon at the top of the Sprites pane. This adds a random sprite to our scene. STEP 2 Hmm… we have a bicycle, which isn’t really going to work. Right-click the sprite and select delete to remove it from the Stage. Click the new sprite icon to reveal a window with several selections. Open the Fantasy…

Python has become one of the most popular high-level programming languages in use since it’s release twenty-six years ago. It’s a more powerful language than that of Scratch and BASIC but not as capable as that of C++ etc. However, it’s still an impressive programming language to learn and we will help you get started. Python Shell Python’s IDLE (Integrated DeveLopment Environment) has a Shell. The Python Shell enables you to interact with your programs and it makes it a lot easier to figure out what’s going on. Run Python in IDLE The program you write in the IDLE Editor is run inside the Python Shell. Choose run > Python Shell to run a program or press F5. You will be prompted to save your program when you run it.…

FUNKY FUNCTIONS A function is a command that you enter into Python that does something. It’s a little piece of self-contained code that takes data, works on it, and then returns the result. STEP 1 It’s not just data that a function works on. Functions can do all manner of useful things in Python, such as sort data, change items from one format to another and check the length or type of items. Basically, a function is a short word that’s followed by brackets. For example, len(), list() or type(). STEP 2 A function takes data (usually a variable) works on it, depending on what the function is programmed to do, and returns the end value. The data being worked on goes inside the brackets, so if you wanted to…

The Raspberry Pi has become famous not just for being an affordable, mini computer but also for the amazing projects that have been dreamt up by its ever increasing userbase. We’ve seen the Raspberry Pi taken into space onboard the International Space Station, used as a media server in the living room, to control robots and even used in conjunction with other Raspberry Pi’s to form an interconnected super computer. We look at some of the brilliant, challenging and fun projects that you can accomplish with your Raspberry Pi, as well as including some of the many robot kits available, that you can use to astound and amaze your friends and family.…

GETTING RETRO An emulator turns your modern Raspberry Pi into an older machine. It pretends (emulates) the classic computer or games machine. There are lots of emulators available, but the best one for Raspberry Pi is called RetroPie. STEP 1 You’ll need to install RetroPie on an SD card. Download the latest version of RetroPie from blog.petrockblock.com. Now use SD Card Formatter (www.sdcard.org) to erase your SD card. It should be 4GB minimum, although we recommend 8GB if you want to use RetroPie to play games. STEP 2 When the RetroPie image has downloaded, unzip it and copy the image to the SD card using sudo dd (on a Mac and linux machine) or win32 Disk Image (sourceforge.net/projects/win32diskimager/) on a windows PC. Follow the guide for installing Raspbian (raspberrypi.org/downloads) if…

APACHE Apache is an incredibly popular web application that runs more than half the servers on earth. Most websites you visit are delivered to you using Apache and it’s free to install and very easy to set up. STEP 1 Open a terminal window, click LXTerminal in the Launch Bar, and enter sudo apt-get update. This will ensure that apt-get is using the latest versions of all its software. While it’s not vital to do this, it’s a good habit to get into from now on before installing any new software. STEP 2 Now lets install Apache. Enter sudo apt-get install apache2 apache2-doc apache2-utils. You will be asked if you want to continue; enter y and press return. This installs the latest version of Apache 2, the Apache 2 documentation…

READY TO ROLL Our robot still has a way to go to be complete but with the servos and wheels attached to the motor control unit and the power in place, it’s ready to start rolling around. STEP 1 You should have all six wires attached to the EduKit Controller Board unit. Double check that the black wire from the battery is going to GND and the red wire to VIN and that the black and red wires to Motor A and Motor B are the mirror opposite way around (as shown in this photo). Gently push the motor control unit into the GPIO pins on the left side. STEP 2 Now it’s time to power up your robot and see if it moves. Attach the battery pack to the…

GETTING TO KNOW GIT Git is online versioning software that enables you to store code online, download code, make changes and then integrate those changes. It enables many people to work together on software. Github (github.com) is a website that developers use to host links to the code. STEP 1 Git enables you to clone code created by other developers on your Raspberry Pi. So it’s a vital tool to have on your Raspberry Pi. You install Git using APT. First enter sudo apt-get upgrade to get the latest package lists and sudo apt-get install git to install the latest version of Git. STEP 2 Enter git –version to make sure it’s installed correctly. You should have the latest version installed (ours is 1.7.10.4). You can enter git –h to…

DO YOU NEED A SCREEN? Not every Raspberry Pi project will need a display, but even the simple ones can make it easier to understand what is going on inside the hardware when working on projects. PRICE: £34.99 / €39.54 PAPIRUS EPAPER / EINK SCREEN ePaper is a display technology that mimics the appearance of ink on paper. Unlike conventional displays, ePaper reflects light, just like ordinary paper, and is capable of holding text and images indefinitely, even without electricity. Because of this, ePaper displays and single board computers or microcontrollers are a match made in heaven, as together they use a very small amount of power whilst still bringing a display to your project. This ePaper display is designed as a HAT and has a 2.7 inch screen size.…

TROUBLESHOOTING YOUR RPI The Raspberry Pi is a surprisingly stable bit of kit, but there is always the chance of encountering problems. If you’re really stuck there are apps available which can help diagnose problems on the RPi. RED POWER LED IS BLINKING A blinking red power LED indicates problems with the power supply. On model A and B, it is hard-wired to the 3.3V power supply rail. If it is blinking, it means the 5V power supply is dropping out. Use a different power supply. On the model B+ and also the A+, the circuit has been improved to give a much more reliable warning of poor power quality. The red power LED is wired to an APX803 supervisor which kicks in when the 5V power supply drops below…

The Raspberry Pi is a British built low cost computer that enables everybody to learn computing, start programming and explore basic electronics. It’s the size of a credit card but capable of running a full operating system and doing everything a desktop does. More importantly, with the Raspberry Pi you install your own operating system, connect all your devices and create your own programs using languages like Scratch and Python. There’s no case so you can hook up electronic circuits to the pins and control them to get input and output, so you can hack together electronic projects at home. Setting up a Raspberry Pi is pretty simple, and throughout this book we’ll take you step-by-step from unboxing your Raspberry Pi to setting it up and getting started. There are…

ASK AROUND The kit list required to set up a Raspberry Pi is pretty basic: keyboard, mouse, HDMI monitor, SD Card and an optional case. Many of these items you’ll already have, but don’t rush out and buy those you don’t. Ask around to see if anybody you know has spares. STEP 1 The most important thing you need is an SD Card. These are the storage cards commonly found in digital cameras. All modern Raspberry Pi boards, including the Raspberry Pi 3 and Pi Zero, use Micro SD cards but the older boards may use a larger SD Card. STEP 2 The SD Card plugs into the SD Card socket. On the Raspberry Pi 3 and Pi Zero you push the card in and pull it out. On some…

PARTITIONING AN SD CARD In this feature we’ll format an SD Card using the Terminal in Ubuntu Linux. Formatting an SD Card in this manner is a detailed process but learning to format a card using command line instructions will stand you in good stead for using a Raspberry Pi. STEP 1 The SD Card needs to be formatted using the FAT32 format. The best way to do this in Linux is to use the fdisk command in a Terminal window. Open Terminal in Ubuntu by clicking Search and entering Terminal; alternatively press Command-Alt-T to open a Terminal window. STEP 2 You’ll need sudo (or root) access to format the memory card. Check that you have sudo privileges by typing sudo -v in the command line. You will be prompted…

SET UP ETCHER Installing with NOOBs is fine but as you become more familiar with the Raspberry Pi you’ll want to install from image files. STEP 1 First install the Etcher app. Open etcher.io in the web browser and click the Download for Windows, Download for Mac or Download for Linux button depending on your system. The installation file will be saved to your Downloads folder. STEP 2 Wait for the installation file to finish downloading and open the Downloads folder. Double-click the “Etcher-win32-x64” setup application and follow the installation instructions. If you’re on a Mac, drag the Etcher file to the Applications folder and double-click it to open the program. STEP 3 Return to your web browser and download the Raspbian Jessie with PIXEL image from the Raspberry Pi…

GET TO KNOW PIXEL PIXEL stands for “Pi Improved Xwindow Environment, Lightweight”. It’s a lightning fast and energy saving desktop that looks a lot better than its predecessor. PIXEL is a great interface that makes it much easier to use a Raspberry Pi than entering text commands. STEP 1 STARTING PIXEL The PIXEL interface is installed alongside Raspbian OS. By default the Raspberry Pi launches into PIXEL. You will see a photographic picture of a road taken in Iceland. STEP 2 OPENING PROGRAMS The Raspbian operating system packs a bunch of programs for you to try out. Click on Menu and choose Programming > Scratch to open the popular tool for learning programming. The program appears inside a window. The buttons in the top right of the window are Iconify,…

ADVANCED PACKAGING TOOL Add / Remove Software is great for finding and installing software but most of the time you manage apps on a Raspberry Pi using a program called APT (Advanced Packaging Tool) using the apt command. STEP 1 To manage the apps on your Raspberry Pi you’ll need to use a tool included with Raspbian called APT (Advanced Packaging Tool). APT is a command line tool so you need to either start your Raspberry Pi in the command line. click on the Terminal icon. STEP 2 The command used to control packages in Raspbian is apt Type apt into the terminal and press Return to get a description of what the app does. The instructions tell us that the “most frequently used commands are update and install”. You…

EXPAND AND COMPRESS FILES Many files are compressed when sent across the Internet. The Raspberry Pi has a built in utility called Archiver used to expand and compress files. STEP 1 Compressed files can be viewed in the File Manager application and they often end with a .zip extension (although other compressed file types exist, including bz2, tar and gzip). Compressed files can be identified by the opening box icon. Double-click a compressed file to open the Archiver app. STEP 2 If the Choose Application window appears, open Accessories and highlight Archiver. Tick “Set selected application as default for this file type” and click OK>. Archiver displays the folder inside the compressed file. STEP 3 Double-clicking a file inside Archiver temporarily expands that file and opens it in a compatible…

EDITING TEXT You’ll spend a lot more time editing text and files in Raspbian than you’re probably used to on a Windows or Mac computer. Raspbian comes with a built-in text editor called Leafpad. STEP 1 Choose Menu > Accessories > Text Editor to open the Leafpad application. It works very much like other text editors where you enter text into the window. There is no built-in spell checker or grammar checker in Leafpad; we’ll look at LibreOffice later for more powerful document editing. Rather than being used for word processing, Leafpad is typically used to edit configuration and code files. STEP 2 Save your new file by choosing File > Save As (or press Shift-Control-S). Enter a name for your document in the Name field and use the Save…

The Raspbian operating system is Linux based, which in turn is a Unix-like OS. Having knowledge of how Unix works, how the file system is structured and how you go about finding your way around the system is vital to every Raspberry Pi user. Unix, and thus Linux, is very different to that of Windows and in some cases even macOS. Being able to list and move files and folders, delete files, create directories, edit text files and even view the system processes can help you massively as you become more adept at using the RPi; and of course it aids you in setting up fantastic future projects.…

MANAGING FILES AND DIRECTORIES Now that you know how to create files, you’ll want to learn how to make directories, which are the same thing as folders, as well as move items around. If you are more used to working with a desktop interface, this can take a bit of getting used to. STEP 1 Enter ls to quickly view all the directories currently in in the home location. Directories are created using the “mkdir” command (make directory). Enter mkdir testdir to create a new directory in your home directory. Enter ls again to see it. STEP 2 The “mkdir” command is different to touch, in that it doesn’t update the timestamp if you use it with a directory that already exists. Enter mkdir testdir again and you’ll get the…

TEXT EDITING Files in Unix are all constructed of text and code, which is text. Often you’ll be asked to open a file, and insert or adjust the text inside. As you get more advanced, you’ll be creating and editing configuration files and your own programs. STEP 1 You’re probably used to editing files in the LDXE environment using a text editor, such as Text Edit. If you’re in the command line, enter startx to enter the desktop. Open Text Edit (Menus > Accessories > Text Editor). We’ve written out a Haiku poem and saved it using File > Save As. Enter the name Haiku and choose the Documents directory. Click Save. STEP 2 We’re going to back out of the desktop environment and into the command line. We just…

LOTS OF UNIX Unix is a huge and versatile command line language, and there are hundreds of commands you can learn and use. Here are some that will help you get more from your Raspberry Pi. STEP 1 The Raspberry Pi is a great little computer, so let’s start by getting some information. Enter cat /proc/cpuinfo to view some details on your Raspberry Pi processors. If you have a Raspberry Pi 3 you will see four processors, along with the model name and other info. STEP 2 Remember that cat is used to list the contents of a text file, which is what cpuinfo is. There are other text files with system info available. Try “cat / proc/meminfo” to get information about your memory, “cat /proc/ partitions” for information about…

IT’S YOUR UNIX One of the joys of working from the command line is that you can customise it to your heart’s content. Discovering how to customise the command line also teaches you a bit about how your Raspberry Pi hardware gets going at startup, so it’s a lesson worth learning. STEP 1 One of the reasons for getting a Raspberry Pi is to learn more about how a computer works. One question is, how does it start? How does the Raspberry Pi know what to do when you hit the power switch - known as booting the computer, because you kick it into action. What happens when you put your boot up the Raspberry Pi’s bottom? STEP 2 When you power up a Raspberry Pi, it fires up the…

LIGHT THE FUZE Getting the FUZE up and running is as simple as plugging in a standard desktop computer; but it’s always worth running through the process for those who don’t know what to do. STEP 1 Before you power up your FUZE, make sure that the provided SD card is inserted into the SD card slot to the rear IO backplate of the FUZE workstation. The chances are the SD card is already inserted but depending on how the FUZE was packaged, it may be in the electronics kit box. STEP 2 Grab a spare monitor or if your existing monitor (or TV) can support more than one HDMI connection even better. The FUZE comes with a quality HDMI cable, remove it from its bag and connect one end…

“PALE BULBOUS EYES STARE AT YOU…” A text adventure game is an ideal genre to explore your BASIC skills in. There are variables, events, user input, counting and if you want, even a few graphics here and there to inject and use. STEP 1 Enter the Program Editor and begin with a simple clear screen, as it’s always a good way to start. What we need to do is set some basic parameters first, so start with the number of lives a player has, for example 3. Cls Let lives=3 STEP 2 Now you can introduce the game and let the player know how many lives they currently have. You can do this by adding the following to the code: Printat (41,0); “You have “; lives; “ lives left.” Printat…

GPIO PINS The Raspberry Pi’s GPIO pins act as a physical interface between the Raspberry Pi and electronic items. On the FUZE these are safely connected to the IO board, and can then be connected to your breadboard. STEP 1 Remove the 9V battery and battery clip if it is still connected to the breadboard, and slide the breadboard into the top of the FUZE so the wires and LED are near the IO board. Let’s take a closer look at what the IO board has to offer. STEP 2 If you look closely at the IO board you’ll see a section of pins marked “RPI Header”. These match the pins that are on your Raspberry Pi. On the right side of the board are a number of output sockets.…

CODE STRIPPING Many of the legendary programmers from the golden era of home computing stripped the code from snippets posted in the magazines of the time. They bent the code to their will and created something as close to magic as possible. EXAMPLE 1 Amiga owners will have fond memories of their futuristic computer back in the late ‘80s and early ‘90s. The Amiga was a pretty impressive home computer, even by today’s standards and its iconic Bouncing Ball routine will forever be remembered by those who grew up with one. Load up aball.fuze from Demos and see what you can use. EXAMPLE 2 Whilst an analogue clock on the screen, complete with second hand, may not sound too interesting, there’s a surprising amount of useful code within this particular…

VISUAL CODING The scripts in Scratch are created by snapping together blocks. These blocks are similar to the ocde you find in more complex programming languages, such as Python, but much easier to understand. STEP 1 Start a new Scratch project (choose File > New) and save it as Dancing_Cat. You’re going to put our cat and some other characters on a dance floor and get them to bust some moves. Click Stage, then Backgrounds and Import and choose party-room. Drag the Scratch Cat graphic around the Stage to find a good starting position. STEP 2 Click on Sprite1 in the Sprites Panes and click the Scripts tab above the Scripts area. Make sure you can see the cat graphic and Sprite1 above your. Now click Control in the Blocks…

MORE INTERACTION Earlier we looked at how you could interact with scripts using the keyboard to move the sprites but scripts and sprites can also interact with each other, sending messages and responding to events. STEP 1 Scripts can broadcast messages to each other. These can be used to start other scripts or to respond to events. You’re going to get Your ScratchCat object to respond to the Monster and say “Watch Out!!!” if the two sprites touch. Select ScratchCat in the Sprites Pane so you can view its Script Area. STEP 2 If is a big word in a computer program. Programs work around a few simple terms and “if this then do that” is one of them. On our stage, you want to say: “if Monster touches ScratchCat…

IDLE PYTHON We’re using the Python 3 IDLE in these tutorials, IDLE stands for Integrated DeveLopment Environment, or Integrated Development and Learning Environment. STEP 1 Let’s start by opening the Python 3 IDLE. Choose Menu > Programming > Python 3 (IDLE). As we mentioned, Python 3 is the latest standard and whilst some of the code arrangements are different to that of Python 2, it makes sense to be up to date with the language. STEP 2 Python will launch into the Python 3.4.2 Shell; the version number is regularly updated so don’t worry if yours is a more recent version. In here you’re able to enter programming commands directly. For example, start with: print (“Hello everyone!”) and press Enter. STEP 3 Just as with FUZE BASIC, and other programming…

TRUE CONDITIONS Keeping conditions simple to begin with makes learning to program a more enjoyable experience. Start then by checking if something is TRUE, then doing something else if it isn’t. STEP 1 Let’s create a new Python program that will ask the user to input a word, then check it to see if it’s a four-letter word or not. Start with File > New File and begin with the input variable: word=input(“Please enter a four-letter word: “) STEP 2 Now you can create a new variable, then use the len function and pass the word variable through it to get the total number of letters the user has just entered: word=input(“Please enter a four-letter word: “) word_length=len(word) STEP 3 Now use an if statement to check if the word_length…

PI MUSICBOX You can turn your Raspberry Pi into a cracking music centre. Add the Pi MusicBox software and connect your Raspberry Pi to a set of speakers. STEP 1 Download the Pi MusicBox software from www.woutervanwijk.nl/pimusicbox. The process for installing the Pi MusicBox image is the same as when installing Raspbian. Use dd bs=4m if=~/Downloads/musicbox0.6/ musicbox0.6.img of=/dev/rdisk4 on a Mac or linux computer or win32DiskImage on a windows PC. STEP 2 Once the image files are copied to the SD card, use the file manager to browse the MUSICBOX SD Card and open the config directory. Open the settings.ini file in a text editor. Scroll down to find wifi_network=”” and wifi_password=””. Enter your network and password details inside the quote marks. Save the file. STEP 3 Eject the SD…

PORTABLE POWER The Portable Games console uses a PiJuice (pi-supply.com), and a portable power pack for the Raspberry Pi with intelligent power functionality. This makes it possible for you to create projects that operate out in the world, such as our Portable Games Console. STEP 1 First you’ll need to get all the parts. Along with the PiJuice and Adafruit 2.2-in TFT screen, you’ll need an Arduino Pro Mini, Analgue Joystick, 4 tactile switches and jumper leads. A complete list of materials can be found at: instructables.com/id/Raspberry-Pi-Portable-Games-Console. STEP 2 The Portable Games console uses Adafruit Cupcade (designed for Adafruit’s Raspberry Pi Micro Arcade Cabinet). You can pick up a copy of the image file from learn. adafruit.com/cupcaderaspberry-pi-micro-miniarcade-game-cabinet/ hardware-setup. It’s a good idea to set up the Raspberry Pi as normal…

BUILDING A CASE What’s better than a Raspberry Pi? Six Raspberry Pis all strung together to create a supercomputer known as a “bramble”; that’s what. Sung-Taek Kim, a software engineer from Korea has created the Pi Spark project (pocketcluster.wordpress.com). STEP 1 With a bit of networking skill and the right project you can string multiple Raspberry Pis together. You’ll need six Raspberry Pi 2 models and a lot of wires and cables. This is housed in a unit made from four boards. Get the Schematics from github.com/stkim1/pocketcluster/. STEP 2 Used the schematics to get the boards cut. You can use a variety of materials, but the most popular way is to use a laser cutter with acrylic. If you don’t have your own cutter, then find a cutter near you…

ULTRASONIC AND LINE SENSING Our robot has two sensors, an Ultrasonic and a Line Detector. The Ultrasonic is the one that looks like eyes and fits into the breadboard. The Line Detector has a small blue camera on one side and fits underneath the robot. STEP 1 Open the CamJam website (camjam.me/?page_id=1035#worksheets) and download Worksheet 4 and Worksheet 5. Worksheet 4 is just for the Line Detector, while worksheet 5 is for both sensors. Make sure you take a good look at the Building the Circuit diagram in Worksheet 5 and keep it with you during this tutorial. STEP 2 Make sure that the robot isn’t currently powered. If it is use VNC and shutdown the Raspberry Pi and disconnect the power to the Raspberry Pi. Locate one of the…

CHOOSING THE RIGHT CASE There are literally thousands of cases available for the Raspberry Pi, and choosing the right one can make a difference as to how easy it is to complete your planned project. Think carefully before you buy. PRICE: £13 / €14 PIBOW RAINBOW Pibow Rainbow is a sleek, durable and attractive case crafted out of eight unique coloured layers with a transparent top and base that will leave your beautiful Raspberry Pi visible inside. Each layer is laser-cut from colourful high quality cast acrylic and once stacked they securely contain a Raspberry Pi 2 or Model B+ while leaving the primary ports, including the camera port, accessible. Weighing only 92 grams the case is lightweight and ideal for mounting to any surface. No tools are required for…

With a Raspberry Pi you can learn to code, build your own web server, create interesting and amazing projects and even build a robot. This book will help you through the entire Raspberry Pi experience, from buying your first RPi to getting it up and running and beyond. We look at how the Raspberry Pi works and guide you through the inner workings of the operating system. We also take a look at the FUZE Project, an amazing learning environment that utilises the versatility of a Raspberry Pi and presents it in a unique and retro-inspired keyboard case. You’ll learn how to start coding, using FUZE BASIC, Scratch and Python and how to use the breadboard for electronics projects. If you’re stuck for project ideas, we will guide you through…