raspberry pi arch linux owncloud bash

232 Pages·2015·61.28 MB·English

RASPBERRY PI ARCH LINUX OWNCLOUD BASH
CYRUS AND PROCMAIL MOUSE-FREE COMPUTING WRITE ONCE, PUBLISH ANYWHERE
SERVE EMAIL TILING WMS MARKDOWN
Forget Google – take control of Master the awesome i3 window Future-proof your words with this
your email by hosting it yourself manager for maximum speed lightweight markup language
TUTORIAL
MEGAPACK
The best hands-on guides, tips and tricks for your Linux box
222 PAGES OF TUTORIALS
ENCRYPTED COMMUNICATIONS Chat securely using Tox
OPEN MEDIA VAULT Turn your old PCs into NAS boxes
SHELLSHOCK Understand how the Bash vulnerability works
SYSTEM MANAGEMENT CLASSIC COMPUTING RASPBERRY PI PROJECT
SYSTEMD THE ATLAS HOME ARCADE
Take control of what starts and Learn how to program a Relive the glory days by building
when during boot up supercomputer from the 1950s your own arcade machine
1
PYTHON + MYSQL › SHELL TRICKS › UEFI › LATEX + MORE!
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WELCOME
Linux for everyone
Where would the world be without Free Software?
Linux Voice is different.
Linux Voice is special.
Here’s why… GRAHAM MORRISON
A free software advocate
At the end of each financial
1 and writer since the late
year we give 50% of our 1990s, Graham is a lapsed
profits to a selection of KDE contributor and author
organisations that support free of the Meeq MIDI step
software, decided by a vote among sequencer.
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Linux has developed into an incredibly versatile operating SUBSCRIBE
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after first publication, we the cheapest smartphones, and businesses around the ON PAGE 57
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the Creative Commons CC-BY-SA companies to avoid vendor lock-in. In practical terms, nothing
licence, so that old content can beats GNU/Linux as the best all-round mainstream operating
still be useful, and can live on even system in use today.
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the shelves. Free Software operating system is also the best geek toy in the
world. It’s great to play with – to explore, to pull apart the pieces,
We’re a small company, so see how they work, and (hopefully!) put them all back together
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we don’t have a board of again. So as thanks to the awesome Free Software community, we
directors or a bunch of at Linux Voice have decided to give away over 222 pages of
shareholders in the City of London tutorials from previous issues of the magazine. Whether you’re a
to keep happy. The only people home desktop tinkerer, a server admin or a budding developer,
that matter to us are the readers. there’s something here for everyone. Indeed, you can even brew
your own beer with Linux! Time to explore…
Graham Morrison
THE LINUX VOICE TEAM
Editor, Linux Voice
Editor Graham Morrison
[email protected]
Deputy editor Andrew Gregory
[email protected] What we love in this megapack
Technical editor Ben Everard
[email protected]
Editor at large Mike Saunders
[email protected]
Games editor Michel Loubet-Jambert
[email protected]
Creative director Stacey Black
[email protected]
Malign puppetmaster Nick Veitch
[email protected]
Editorial contributors:
Juliet Kemp, Andrew Conway,
ANDREW GREGORY BEN EVERARD MIKE SAUNDERS
Valentine Sinitsyn, Jon Archer,
Mark Crutch, Les Pounder, “With governments and big “Never lose any important data “Ever since I learnt the i3 window
Mark Delahay, Marco Fioretti, business trying to spy on again with regular backups. It manager, my productivity has
John Lane, Mayank Sharma,
everything we do, encrypting may seem like tedious work, but shot up. I no longer have to keep
email with PGP is essential.” p5 we make it easy.” p175 reaching for mouse.” p211
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Tutorial Megapack Welcome 4sb.indd 3 09/12/2015 14:10
TUTORIAL MEGAPACK CONTENTS
Contents
A vast compendium of GNU, Linux and Free Software knowledge.
comets, from the comfort of your Linux machine.
19 35
Raspberry Pi: build an
emergency beacon 62
Stay safe in the event of disaster by broadcasting
the theme from Star Wars from a lunch box.
Control virtual machines with
Python and libvirt 66
Dispense with the GUI for the awesome power of
virtual machines commanded by Python.
PGP: Keep your messages secure 5 Stay effortlessly* up to date. Make your own typeface with BirdFont 70
Encrypt your emails and reclaim a little bit of *Some effort required Design software has never been more accessible.
privacy from Big Brother/the NSA/GCHQ. Now go and brand something!
Bug reports: help make free
BrewPi: Brew beer at home with software better 27 Raspberry Pi: Build a Mars Rover 72
a Raspberry Pi 7 If you do it right, getting bugs fixed can be an Create robots programmable in Python quicker
Control and monitor the brewing process with the important part of free software development. than you can say “Sarah Connor”.
help of a handy Linux-powered kit.
Raspberry Pi & MAME: build Raspberry Pi: Monitor woodland
OwnCloud: Say goodbye to Google Docs an arcade machine 29 creatures 78
& Gmail 15 Play the games of your youth* without Keep tabs on your local badger population with a
Set up your own cloud services and get the squandering all your pocket money. remote, home-brewed wildlife camera.
convenience of the cloud without the intrusive *Graham’s youth
advertising messages. SSH, Apache & Tiger: Secure
Old code: Grace Hopper and UNIVAC 35 your servers 80
Old code: Ada Lovelace How to program on a machine that weighs more Stay one step ahead of the script kiddies who
and the Analytical Engine 19 than a double-decker bus. want to vandalise your web servers.
Travel back to the dawn of time to see how
programming began – then try it for yourself! KDE: configure the hell out of VirtualBox: Keep Windows XP
your desktop 39 after migration… 84
Arch Linux: Installation and setup The defaults in KDE are an affront to taste and … should you wish to, that is.
made easy 23 decency – so fix it and make your life better.
John von Neumann: EDVAC & IAS 88
UEFI: The new world order of booting 45 The Manhattan project bore strange fruit…
Boot Linux without Grub or a BIOS.
Benchmarking: how fast is
UK SUBSCRIBERS
Customise the LXDE desktop 49 your computer? 92
TURN TO PAGE 57 Make your Raspberry Pi a lot prettier by Test the capabilities of your machine and
enhancing its default desktop environment. persuade the boss to let you get a new one.
Make smart clothes with Raspberry Pi: make games with Scratch 95
an Arduino LilyPad 51 Build a set of traffic lights and a random number
Sew a wearable circuit into clothing to turn your dice-rolling game – both with flashy lights!
wardrobe into an electronic canvas.
Office migration: printing and email 98
Hunt comets with Python and open data 58 Let your small or home office labour no longer
Filter image data in the search for Thargoids under the oppressive yoke of XP. Freedom!
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CONTENTS TUTORIAL MEGAPACK
Compile software from source code 103 Python and MySQL: Big data analysis 150
Get the latest software, extra features and more Don’t trust the official statistics – take the data
speed with home-rolled source code. and make your own.
US SUBSCRIBERS
BASIC and the dawn of the Linux 101: Power up your shell 154 TURN TO PAGE 116
microcomputer 106 Customise the stock Bash command line and
The language that started a revolution. feel epic.
PyParted: partition your disk with Python 110 Fargo: Write and publish outlines
Gain insane levels of geek points. in open formats 158
Turn the web upside-down with a simple way to
Krita: Get started with brush publish content.
modes and layers 118
Paint your masterpiece with Free Software and Write a device driver with PyUSB 162
the Divine Stallman. Reverse engineer the software to control a USB
toy car.
Build a quiz in Python, EasyGUI
and Pygame 120 HDR: Create awesome photographs 169
Use functions, variables and lists to expand your Combine images to achieve stunning visual
programming skills. effects. Latex: Compose beautiful text 197
The layout tool for the über geek isn’t as hard as
Tor: Encrypt your internet traffic 124 Raspberry Pi: Let’s get animated 171 it looks.
You may not have anything to hide, but you can Craft a movie masterpiece with Python and the
still help. Raspberry Pi. OpenMediaVault: NAS for everyone 201
Get network attached storage
Linux 101: Master your package manager 128 Linux 101: Back up your data 175 the easy, Linuxy way.
Find out what’s going on at the heart of your One day you’ll wish you used encrypted backups.
Linux distro. Shellshock: Breaking into Bash 205
John The Ripper: Crack passwords 179 How the scary security flaw works. Now update!
Arduino & Python: Build robotic … then create new ones that are more secure.
weaponry 132 Cyrus: Build your own mail server… 207
Add face recognition software to a toy gun. Cyrus: Build your own email server 183 … and implement bespoke antivirus and spam
Mayhem ensues! Take control of your communications. checking.
Sigil: Create quality ebooks for any OS 140 URWID: Create text-mode interfaces 187 i3: Learn a tiling window manager 211
Self publishing is the future of the novel, so why The interface of the 90s is alive on Make better use of your screen space and kill the
not try it today? low-bandwidth systems. mouse for good.
Raspberry Pi model B: Tox: Encrypted peer-to-peer Raspberry Pi: Use different kinds of input 213
Void your warranty 144 communications 191 Use your Pi to protect a plate of biscuits from
Add bits, hack bits, then overclock it and fry it. Chat without any government spooks listening interlopers.
It’s fun to be a geek. to you.
Markdown: Write once, publish anywhere 217
Sonic Pi: Program electronic music 146 Python: Write a simple Twitter client 193 Publish your content in a simple format that
Code bleeps and beats in a wonderfully simple Connect your application to the weird world of looks here to stay.
syntax. social media.
Linux 101: Get the best out of Systemd 221
Love it or hate it, Systemd is here – you might as
132 171
well use it.
Grub 2: Heal your bootloader 225
How to fix a broken installation without losing all
your data.
Olde code: Atlas – the UK’s
supercomputer 229
How the transistor revolution brought
supercomputing to Manchester.
4
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TUTORIAL PGP
KEEP MESSAGES
SECURE WITH PGP
TUTORIAL
The Feds (and GCHQ, and the NSA) are snooping on our
BEN EVERARD
communications, but we can fight back with encryption
Normal email is one of the least secure forms
of communication available – less secure
even than post cards. These mails can
typically be read by anyone on the same network as
you, anyone at the ISP, anyone at your mail provider,
anyone at the recipient’s ISP and anyone on the same
network as the recipient, as well as anyone with
access to the various networks between the two ISPs.
If you use SSL or TLS to connect to your inbox, then
it improves things a little, but it’s still vulnerable as
soon as it leaves your mail provider. The colour and message in the top-right corner are
PGP (Pretty Good Privacy) is a program designed to a random security code so you can distinguish real
remove these weaknesses. It uses the normal email Mailvelope messages from spoofs.
system, but adds a layer of encryption to protect them
in transit. These days, PGP is usually used to refer to key encryption comes into play. Everyone who uses
the OpenPGP format for these encrypted messages, PGP first creates a public/secret key pair. The public
rather than the PGP program specifically. key is made public while the secret key is known only
The OpenPGP format uses two different types to the user. However, anything encrypted with the
of encryption: symmetric key and public key. In public key can be decrypted only with the secret key
symmetric key encryption the same key (basically and visa versa.
just a binary string that’s used as a password) is used
to encrypt and decrypt the message. In public key Public and private keys
encryption, two different keys are used (one to encrypt The solution is to encrypt the key for the message
and one to decrypt). The phrase ‘private key’ can refer with the recipient’s public key. When they receive
to either the key in symmetric encryption, or the secret the message, they can then decrypt the key for the
key in public key encryption. To avoid this ambiguity, message, and then decrypt the message itself. This
we won’t use the phrase in this article, but you may is a bit convoluted, but it’s much less processor-
come across it in software. intensive than encrypting the whole message using
When encrypting a message with an OpenPGP- public key encryption.
compatible program, the software generates a You can use OpenPGP in most mail clients, but
random symmetric key and encrypts the text. This we’ll look at doing it in webmail. Since OpenPGP is
ciphertext forms the bulk of the message. purely a text format, you could generate the encrypted
The problem is that the recipient of the message message elsewhere and copy and paste it into your
has to know the key, but it can’t be included in the email. That’s exactly what we’ll do, but instead of copy
message otherwise anyone who intercepts the and paste, we’ll use a browser extension to convert
message will be able to read it. This is where public the plaintext to encrypted ciphertext.
Mailvelope (www.mailvelope.com) works with
Chrome/Chromium and Firefox, and it comes pre-
USING OTHER MAIL CLIENTS
configured to work with some of the most popular
We’ve described the process for working mentioned in the main text, you should be webmail providers (Gmail, Yahoo, Outlook.com
with Mailvelope, but the process is almost able to transfer keys between these pieces and GMX). Installing it is no more challenging than
identical for all OpenPGP-compliant of software so you can access the same mail downloading the extension from its Releases section
software. You shouldn’t have any problems account through different programs.
(https://github.com/toberndo/mailvelope/releases)
following along using Thunderbird or Mailpile is a mail client designed to bring
and opening the file with the appropriate web browser.
Evolution, or even AGP and K9 for Android or PGP to the masses by making it easier
Cyanogenmod. to set up OpenPGP encryption, even for The first step is to generate a public/secret key pair.
Regardless of the software, you’ll still new users. The project raised just over In Chrome/Chromium, you can get to this by clicking
have to go through the same process of $163,000 in crowdfunding and is currently in on the padlock icon that should have appeared to the
generating and exchanging keys before development, and you can track its progress
right of the address bar. In Firefox, this options menu
you can communicate with someone. As at www.mailpile.is.
is a little more hidden. First, you’ll need to go to view
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TUTORIAL PGP
DIGITAL SIGNING
OpenPGP encryption ensures that only the intended
recipient can read the message; however, it doesn’t
guarantee that they receive the message, or prove who sent
the message. Encryption can’t help with the first of these,
but there is something you can do about the latter measure.
In many OpenPGP mail clients (and the gpg command
line tool), you can add a digital signature to a clear-text
message. It does this by leaving the message in plain text,
but also encrypting a hash of the message with your secret
key. This encrypted hash is known as a digital signature.
Since it’s encrypted with your secret key, it can be
decrypted with your public key. Any recipient that knows
your public key can then decrypt this hash and check it
against the message. If they match, the recipient knows
that it really came from you.
> Toolbars > Add-on bar. This will make the Add-on or http://pgp.mit.edu. Of course, it is possible that You can send encrypted
bar appear at the bottom of the screen, and then you some attacker could take control of one or more of messages to several
should find the padlock icon on the right-hand side of these key servers and put fake keys in them. Webs people at once, and
Mailvelope encrypts it for
this. This icon will bring up a menu, and you’ll need to of trust have a decentralised method of verifying
each of them.
select Options (see the image, left). keys. It’s done by people digitally signing the keys of
In the Options screen, you can create a new public/ people they’ve met and exchanged keys with. If you
secret (private) key pair by selecting Generate Keys. need to communicate with someone, you can then
Once you’ve done this, you can go to the Display Keys tap into this web of trust and see who trusts them.
screen to see it. This screen will show all the keys Perhaps someone you trust also trusts them. Perhaps
that Mailvelope knows, whether they’re other people’s someone you trust trusts someone who trusts
public keys or your own public/secret key pairs. them. If this chain is short enough, then you can be
Before you can receive emails, you have to send confident that you can trust the person. Unfortunately,
your key to the people you want to communicate with. Mailvelope doesn’t currently support webs of trust.
The key file can be exported from the Display Keys
screen (you can also export your public/private key Keep it secret, keep it safe
pair here and import them into another mail program). As is so often the case, the decision on which way to
Getting the public key to the recipient can be a distribute your key comes down to security versus
challenge. The best way to do this is to physically convenience. If you’re concerned, you could always
transport the key, as you can be completely sure that follow up with another method such as a phone call to
they got it correctly. The easiest way is just to email confirm the key. Once someone has sent you their key,
them the keyfile. However, it’s possible for some you just need to load it into Mailvelope using the
malicious attacker to intercept this message and Import Keys screen in the Options.
change the keyfile. Getting set up with keys is the hardest (or at least,
There are two other options: key servers and webs most inconvenient) part of using any OpenPGP-based
of trust. Key servers are databases of keys that you communication. Once you’ve done this, it’s easy. With
can add your keys to, and retrieve other people’s keys the Mailvelope extension running, just use your mail
from. For example, try http://keyserver.pgp.com provider’s web page as normal (if your mail provider
isn’t already on the Mailvelope watch list, you’ll need to
add it in the Options). When you get to the compose
page, you’ll see a floating icon of a pen and paper.
Click on this and it will open a new window to let you
enter the text for the message. Once you’ve written
the message, click on the padlock, and add one or
more people to the list that it’s encrypted
for, then Transfer to put the ciphertext into the email.
If you receive an encrypted message, Mailvelope
will display a decrypt icon; click on this to enter the
passphrase you entered when you generated the key.
This password gives you some security even if an
attacker gets access to your machine.
You can use gpg to create signed documents from the Provided you exchange keys securely, and keep
command line. Just run gpg --clear-sign <text-file> to your keys safe, OpenPGP provides security that is
generate a file containing the plain text and a signature. thought to be unbreakable with current technology.
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TUTORIAL BREWPI
BREW PERFECT BEER WITH
HELP FROM THE RASPBERRY PI
TUTORIAL
We love beer, we love the Raspberry Pi and we love the Arduino
GRAHAM MORRISON
– so we’re bringing them together for one awesome project.
Beer is lovely. But when you’re making it at
7 STEPS TO BEER
home, the biggest challenge (after discovering
• Brewing a way to boil vast quantities of water) is always
• Cooling finding somewhere to leave your brew to ferment. It’s
• Fermenting this stage of beer-making magic that turns what’s
• Priming known as wort into beer, creating alcohol and oodles
• Bottling of flavour. And for this stage to work well, you ideally
• Ageing need to be able to manage the temperature of the
• Drinking environment your beer is sitting in. In the UK, many
amateur brewers resort to using an ‘airing cupboard’,
normally situated next to the hot water tank and used
for drying clothes. This isn’t a bad place, because it’s The various bits of the BrewPi give little indication that
warmish – many beer kits like to ferment at around they can be put together to create something awesome.
20 degree centigrade – and the temperature doesn’t
fluctuate massively. But it still fluctuates, and it may has its creator, Elco Jacobs, built an incredibly
GENERAL LINUX
even prove too warm. Many yeasts, especially for ale, effective system for fermenting beer, he’s created an
prefer things a little cooler (18–20 degrees, ideally, but extremely helpful community of BrewPi enthusiasts,
this depends on the beer). And lifting 25 litres of wort an online shop and an assembly system for easy
HARDWARE into a first-floor cupboard could break your back, and access to all of the bits and pieces you’ll need.
you’ve got a hygiene nightmare if it falls over, or falls
through the flimsy shelf its sitting on. What you’ll need
BrewPi is the answer to this conundrum. It’s a While you will need a fair bit of kit, it needn’t cost very
brilliant project that brings together a love of Linux, a much. The fridge or freezer is the biggest
little hardware hacking and plenty of beer into one consideration, as well as somewhere to put it. We
DIFFICULTY
fermenting barrel of hoppy goodness. It’s essentially a asked the internet, and Mark Einon in Wales very
device that controls the environment surrounding the generously obliged with a freezer he was going to give
DISCLAIMER fermenting bucket of beer, enabling you to make to the local freecycle initiative (thanks Mark!) Almost
perfect beer every time, regardless of climate and any fridge or freezer will do, as long as it’s working,
The following tutorial
mixes liquid, electricity house heating cycles. Many people use an old fridge and you should be able to find someone willing to let
and DIY modifications, or freezer as the surrounding container and connect an old model go for very little. You need enough space
all of which can create the BrewPi to a cooling and heating mechanism to within the freezer to stand your fermenting bin, and as
a lethal cocktail of
enable its clever algorithms to create the perfect our freezer’s shelves were made from coolant pipes,
danger. Don’t make any
modifications yourself environment for your beer. The BrewPi itself is a we had to bend these back before there was enough
unless you’re certain mixture of hardware, software and initiative. Not only room. Fortunately, the pipes were easily pushed back.
they’re safe, and get a We then slotted in an old wooden shelf to stand the
qualified electrician to
fermenting bucket on, as they can be very heavy when
check any modifications
you do make. full of 25 litres of brewing beer.
If the fridge or freezer has an inside light, this can be
coerced into another essential task – heating up the
inside environment. If not, you’ll need some other kind
of heating mechanism. Some people use a reptile mat
wrapped around the fermenting bin, but we plumped
for a 60W waterproof greenhouse heating bar, which
cost us £15 new on eBay, and slotted nicely into the
bottom of the freezer with plenty of room. You will
also need both a Raspberry Pi, complete with a > 2GB
SD card, and either an Arduino Duo or an Arduino
This shows the rear of the LCD connecting to the Arduino Leonardo microcontroller. If you’re anything like us,
and the shield, with the OneWire connector above. you’ve got an old Duo tucked away in a drawer
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BREWPI TUTORIAL
somewhere and a Raspberry Pi going spare. And
despite the name of the project, there’s no specific
reason for requiring a Raspberry Pi – any Linux device
with a USB port capable of running the Apache web
server and some Python scripts should be up to the
job. You might want to try a NAS, for example, if you’re
running one already. But the Pi is well suited to being
tucked away in the garage, and it’s relatively cheap, so
it’s still a great option. Most of the hard work is done
by the Arduino, as this interfaces with the various
sensors and relays and runs the complex controlling
algorithms that adjust the temperatures within your
freezer. Your brew will even keep brewing if the Pi
crashes, which is handy if there’s a power failure and
your Pi develops a read/write error. The Pi is really just
logging and serving up the data for the web portal.
Unless you’re an expert who’s happy building
circuits, you’ll also need the BrewPi kit (brewpi.com).
This includes everything you need to turn your
Arduino into a sensor-wielding beer factory. It includes the process first, and then experiment a little with an The BrewPi isn’t an easier
the shield, a PCB that slots onto the two compatible old circuit board and some wire. You’ll then be set for way of making beer. It’s
Arduino form factors, along with the LCD, the sensors, the main event. an easier way to make it
perfect.
the actuators (more details later if none of this makes The shield is the bit that attaches to the Arduino,
sense) and the other fiddly bits that may otherwise and it’s probably the most complex part of the whole
take an afternoon to source. It’s even possible to buy assembly, so let’s get this out of the way first. The
the whole thing pre-constructed, but we think that’s main instructions can be found at www.brewpi.com/
missing half the fun, especially when the build itself brewpi-soldering-guide, but we’re going to cover the
isn’t that difficult. broad detail of the process, along with any particular
We’d also highly recommend buying the case kits. notes we make along the way. The official instructions
These lasered bits of plastic encase both your are made up of photos, and while they’re great if you
Raspberry Pi and your Arduino to create a sleek, know what you’re doing, we want to make the project
professional solution that looks great sitting atop your as accessible as possible by making fewer
freezer. They also stop bits getting bashed about or assumptions about the builder than the official site.
falling off. Expect to pay around £70 for the shield and
case kits together. You’ll also need a miscellany of Forging the shield
common tools to put the whole thing together; a First, lay out all the components on a table top,
soldering iron and solder, maybe a solder sucker, grouping them together so you can check they’re all
some tweezers, a range of differently sized there. This also makes it easier to install. Now start by
screwdrivers and a steady hand. being brave – you’ve got to snap the shield apart into
Did we just say soldering iron? Yes! You’ll need to four separate boards. It’s a little like breaking bonfire
solder the various components on to the Arduino toffee. The large board that breaks off (labelled with
shield. But it’s straightforward, and this should make www.brewpi.com) connects directly to the Arduino.
an ideal first project if you’ve not done any soldering Then there’s a long strip embedding seven columns of
before. All the components are large and there’s no three holes, a medium-sized rectangle of a board with
fiddly soldering required. Try watching a couple of a surface mounted integrated circuit, and a tiny
YouTube soldering videos to familiarise yourself with rectangle that will host the rotary encoder.
Break off the broken tabs remaining on the boards
with a pair of pliers or a small pair of cable cutters so
that the edges are as smooth as possible. Some of
the pin arrays – the ones with the two collars of black
plastic – are designed to fit on to your Arduino board
so that it can connect to the holes on the shield. There
are five of them, and you should find there’s one for
every header on the Arduino. These need to be
connected to the Arduino first, before being soldered
into the shield – this locks their orientation and
connection. The longer pin goes into the Arduino,
while the shorter piece goes into the shield. As we
The Raspberry Pi can also fit on top of the BrewPi case, were using an ancient Arduino Uno, there were fewer
in a separate box or au naturel. Cases are good. power headers on the circuit board that pins allocated,
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TUTORIAL BREWPI
Next is what’s known as the OneWire distribution
board (the only board remaining). Sometimes it’s
written as ‘1-Wire’, and it’s a standard protocol for
communicating with devices from Dallas
Semiconductor (such as the temperature sensors we
need for our BrewPi), using a single connector, hence
its name. This needs seven of the three-pin green
connectors – two shaped at right angles for the edge
connectors, and the other five directly pointing up (you
can see this illustrated on the board itself now you
know what to look for, and that’s the side they need to
be connected to). Official instructions suggest starting
with the two outer connectors, as these are oriented
outwards lengthways. The other five all face upwards
with their pins on the left when you’re looking at the
text on the board. The green ‘AT-AT’ connectors (for
Red or blue LEDs on the but the eight-pin array still fitted over the power pins that is what they look like, not an official designation)
shield indicate whether the and the 10-pin header still fitted across the IO pins then plug into these and the two end connectors.
BrewPi is currently heating
without getting in the way of everything coming Now it’s the turn of the rainbow-coloured ribbon
or cooling your brew.
together. Don’t forget there’s also smaller six-pin cable, which we need to turn into something a little
rectangular connector. Fortunately, the shield only fits more civilised to enable it to connect to the ports
one way. Start your soldering at the corners to make we’ve been soldering. If you’ve ever made your own
sure all the pins stay aligned. IDE cable for an ancient PC, this is very similar. The
Now solder the single green connector onto the black plastic connectors that attach themselves to the
ACT1–ACT 4 shield holes, with the component ribbon cable have teeth that penetrate the insulation
attached to the side with the website URL. Connect a on the outside of the wire to make a connection
three-pin green connector to one side, and one of the without soldering anything. Just make sure the
PRO TIP
two-pin connectors to the other (they all offer ports at triangles on the connector align with the black wire in
Soldering tips; heat up
right angles to the board, and have the same the flat cable. Push the cable through until it just
the destination first,
dab the solder onto the connector form factor as the eight-pin one you’ve just protrudes from the other side, and taking the advice of
joint, make sure it flows connected). Ours wobbled slightly while fitting them, the official instructions again, place the smaller edge
into the joint naturally
so it’s best to solder one of the middle pins first and on a table and use something flat to put considerable
and try not to bridge any
connections. If you do, wiggle the connector into alignment, before soldering pressure onto the connector. It should just about
heat and remove using a any remaining pins. Flip the shield over and solder one come together, and in so doing, connect the pins to
solder sucker.
of the 10-pin block connectors to the header labelled the cable. When this seems secure, fold the long end
“To the LCD backpack”, and make sure you’ve got the of the cable up and over the back of the connector
gap in the right place (facing the edge). before sliding the remaining black connector to hold
That’s all that needs to be done to the main board! the cable together. This needs to be done on both
Congratulations. Now might be a good time for a cup sides of the ribbon cable, and both connectors need to
of tea before moving on to the LCD backpack itself. point the same way so that the cable won’t twist. That
last bit can be a little mind bending as you try to work
Glowing electronic display
The LCD board is the one with the small integrated
circuit already on it. The circular speaker fits into the
middle with the upwards side on the same side as the
chip, and after soldering, you need to cut the
protruding pins from the other side. Another 10-pin
header comes next, with the gap facing the integrated
circuit. Flip this small board over (to the side without
any components), and fit the 16-pin header into the
holes. Solder from the other side.
The tiny board for the rotary encoder is up next. The
official instructions mention that the biggest two pins
on the encoder need to be squeezed slightly to fit into
the holes. We didn’t need to do this, but we did need to
use a fair amount of strength to get the encoder into
position. Make sure the side with the handle is the one
with the circle on the board, and solder the joints from
the other side. A washer, a nut and then the handle We had to bend one of the shelves in our freezer to make
can be slipped over the encoder when you’ve finished. enough room for the fermenting bin.
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BREWPI TUTORIAL
THE BREWPI SURVIVAL KIT
The flat packed The LCD, which fits
Raspberry Pi and into the hole in one
Arduino shield cases. of the case panels.
Shield parts are
mostly soldered
Temperature sensors are
onto the shield,
used to measure the beer
but our kits had a
temperature, the freezer
few bits left over.
temperature and the
outside temperature.
The shield itself.
out which way to put the connector on so that the enough to solder the lone pin alongside the others.
black cables stay in the same place and the connector Solder these pins on the top surface (the same side as
is pointing in the same direction after you’ve twisted the LCD itself), and you can now attach the LCD to the
the cable back over the connector. You can now female header.
connect both of the boards with the correctly sized The final stage of shield forging is to take the
connector together with the cable, and we felt slightly sensors and strip the insulation off the end of the
more optimistic after testing the continuity of the wires – a couple of millimeters will do. Each cable has
connections to make sure we’d pushed through the three ‘cores’, and each core needs to be screwed into
connectors to the ribbon cable with enough pressure. a three headed ‘AT-AT’ green connector, so that when
For the other ribbon cable, pull off the ends where these plug into the OneWire board, red is at the top
they’ve been cut and wiggle this into the underside of (marked 5V – this is important), and yellow at the
the rotary controller board. Pin 4 should always be red. bottom. The official instructions note that the colour
Then solder the pins to the board, The other end of order of the yellow and green wires has changed, so
this cable goes to the LCD board, parallel to the it’s worth making doubly sure if you’re reading this in
rainbow ribbon cable, and connected to the same the distant future, as the sensors might not be able to
side. Make sure pin 4 lines up and solder this as well. take 5V going in the wrong cable. To make the ends of
The next stage is the LCD, and you first need to the wires easier to insert into the tiny screw holes, and
break off 16 pins for the LCD itself. The official guide to make them more resilient, it’s worth dabbing them
has a great tip, where you connect the whole header in a little molten solder.
to the female header on the other board and use this
as a guide for snapping the 40-pin header at the right Porter, Stout, IPA – and the case
place with your hands. This didn’t quite work for us, as You now have a choice. You can either keep the
we broke the header one pin short, but it was easy OneWire connector close to the rest of your BrewPi
hardware, or place it closer to where the sensors are
going to be. This might be useful if you wanted to
position the OneWire board within the fridge, for
example, but we decided to go with the official
instructions and wire up a short three-core cable
(maybe 20cm), with AT-AT connectors at either end, to
connect the OneWire board to the BrewPi. We used an
old power cable with earth for easy access to three
cores with insulation attached. This cable eventually
loops outside the case from the main board to the
OneWire connector.
The cases are all made from various bits of lasered
plastic, and it’s never clear exactly what goes where.
To make the sensors inside the fridge easily removeable, It’s like a BrewPi 3D jigsaw puzzle. The Raspberry Pi
use a connector like this within a container. case is a good place to start, as this is emblazoned
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