Linux User & Developer 169 - Electronics for Pi Hackers

100 Pages·2016·19.495 MB·English

by  April Madden

FREE DVD WITH 5 LIVE BOOTING DISTROS
www.linuxuser.co.uk
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» Linux Mint 18 on test
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THE MAGAZINE FOR
THE GNU GENERATION
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Editor April Madden
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Designer Rebekka Hearl This issue
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Editor in ChiefDan Hutchinson

Publishing DirectorAaron Asadi
Head of Design Ross Andrews » Electronics for Pi hackers
Contributors
Dan Aldred, Mike Bedford, Joey Bernard, Christian Cawley, Sanne » Ultimate rescue kit
De Boer, Kunal Deo, Alex Ellis, Tam Hanna, Oliver Hill, Phil King, Jon
Masters, Paul O’Brien, Swayam Prakasha, Richard Smedley, Jasmin
Snook, Nitish Tiwari, Mihalis Tsoukalos and Kevin Wittmer » Revitalise an old laptop
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Assets and resource fi les for this magazine can now be found
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Support fi [email protected] story since its launch in 2012, and it’s at the heart of many
International
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H☎e a+d4 4of (I0n)t 1er2n0a2ti o5n8a6l 4L0ic1ensing Cathy Blackman a great device for getting people coding, but what about if
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☎PP☎rro o00dd11u22uc00tci22ot ni55o D88ni66re22c00t00or Jane Hawkins oiLsnos 2ou2ke S f1oe7rp0 t soAldlseori tnhgi.s T iaskseu ey oyuoru m’ll afi knedr tphreo juelctitms atote t hrees nceuxet kleitv oenl t ooudra fyr!e e DVD.
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58 Electronics for Pi Hackers
Learn to build electronic circuits to interface with your Pi
SSppoottiiffyy Audacious
OpenSource Tutorials
08 News 30 Bash masterclass: Find files
T he biggest stories from Computers are good at storing fi les. Bash TOMAHAWK Clementine
the open source world scripts makes fi nding them again easier
12 Interview 34 .NET reboots on Linux with 90 Linux Mint 18
Boken Lin from Onion on the .NET Core Distrowatch’s favourite continues on in
Omega2 board Explore the new open source .NET leaps and bounds
runtime and SDK
16 Kernel column 92 Free software
The latest on the Linux 38 Revitalise an old laptop Richard Smedley recommends some
kernel with Jon Masters Give an old laptop a new lease of life excellent FOSS packages for you to try
with lightweight Linux
42 Automate your project tasks
with Ansible
Learn how to install and use Ansible and
Ansible Tower to automate tasks
46 Manage the system on
Ubuntu Linux
Take a closer look at how you can manage
the system within Ubuntu
50 Learn Go: Develop programs that
Features
read and write to files
LLeeaarrnn hhooww ttoo ddeevveelloopp aanndd uussee GGoo ppaacckkaaggeess
18 Ultimate rescue kit
Ten ways to fix your PC with 57 Practical Raspberry Pi
our rescue disc Continue our Explorer robot and toy
hacking tutorials, get RISC OS on your
58 Electronics for 96 Free downloads
Pi, check mail with a Python script and
Pi hackers Find out what we’ve uploaded to our digital discover key electronics skills
Take maker projects further content hub FileSilo for you this month
Join us online for more Linux news, opinion and reviews www.linuxuser.co.uk
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Open Source
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Welcome to the Linux User & Developer DVD. for PC problems. Just restart your computer your computer and double-click
Save your system from data loss, fi x boot and boot from the DVD to access the fi ve live- the icon.
problems, interrogate partitions and hard booting distros. Plus there are two great FOSS Live boot
drives, and much more with the ultimate rescue programs for recovering data from hard drives
kit. This live booting disc is your one-stop triage and storage media. To live-boot into the distros
supplied on this disc, insert the
Featured software: disc into your disc drive and
reboot your computer.
Please note:
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from disc (press F9 on your
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change Boot Options).
• Some computers require
you to press a key to enable
booting from disc – check your
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KNOPPIX from the disc: they will not be
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KNOPPIX is a bootable live system consisting of a
Puppy Linux is a special build of Linux meant to make representative collection of GNU/Linux software, to do so.
computing easy and fast, even allowing you to do magic automatic hardware detection, and support for many
by recovering data from destroyed PCs or by removing graphics cards, sound cards, SCSI and USB devices For best results:
malware from Windows. and other peripherals.
This disc has been optimised
for modern browsers capable of
CloneZilla
rendering recent updates to the
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SystemRescueCd CloneZilla is a partition
and disk imaging/cloning to get the best experience we
SystemRescueCd is a Linux system rescue disk program similar to True recommend you use:
available as a bootable CD-ROM or USB stick for Image or Norton Ghost.
• Internet Explorer 8 or higher
administrating or repairing your system and data after a It helps you to do system
crash. It aims to provide an easy way to carry out admin deployment, bare metal • Firefox 3 or higher
tasks on your computer. backup and recovery. • Safari 4 or higher
• Chrome 5 or higher
Trinity Rescue Kit ddrescue 1.16
Problems with
Trinity Rescue Kit or TRK is a free live Linux distribution GNU ddrescue is a data recovery tool. It
that aims specifi cally at recovery and repair operations copies data from one file or block device the disc?
on Windows machines, but is equally usable for Linux (hard disc, CD ROM, etc) to another, trying
recovery issues. to rescue the good parts first in case of read errors. Send us an email at linuxuser@
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08 News & Opinion | 12 Interview | 96 FileSilo
Hardware
$8 Raspberry Pi challenger revealed
The NanoPi Neo is big
on features, but for a
wallet-friendly price
Of course the raspberry Pi is no expensive
piece of kit; in fact, it’s one of the best ways
for budding builders and tinkerers to get
themselves started with computing without
breaking the bank. With units of the original
Pi and its numerous successors selling in their
millions, it was inevitable that a whole host of
competitors would try and get in on the action.
We’ve encountered many of them during our
time on Linux User & Developer, and it’s truly
hard to beat the value for money and ease-of-
use that the Raspberry Pi can offer.
One of the newest, and also arguably
one of the best, to arrive on the scene is
the NanoPi NEO. Produced by the relatively
well known FriendlyARM brand, the biggest
selling point of the tiny computer is its $8
price tag. But it’s not until you take a closer
look at the internals of the NanoPi NEO that
you realise just how much of a steal it is at
that price for both beginner and advanced
users alike. The NanoPi NEO is available
with 256MB and 512MB of RAM, with the
larger variant only slightly more expensive
at $10 and worth the upgrade for the added
power. It’s also remarkably smaller than
other noted competitors, with a 40mm
square board powered by the Allwinner H3
quad-core processor clocked at 1.2GHz. For
above The 40mm square board is one of the smaller Pi competitors on the market
most beginner-level projects, that’s more
than enough power, and FriendlyARM itself themselves on its website. The processor and The NanoPi Neo comes pre-loaded with
lists a number of projects for users to try out RAM combination is also much faster than the Ubuntu, but it’s also being marketed as
Pi Zero’s offering, but it’s slightly less than the being adaptable to work with many other
bigger Raspberry Pi models. distributions. The number of ports also allow
Expect to be able to build
Dig even deeper and you’ll ind a 10/100 it to work with many other expansion sets. So
things like a USB camera, Ethernet port, three USB 2.0 ports and an expect to be able to build things like a USB
additional microUSB port. Despite its size, camera, a GPS system, a USB Wi-Fi device
a GPS system, a USB Wi-Fi
there’s also room for a microSD slot and a and a multi-media streamer. The only real
device and a multi-media debugging serial port to top it off. Expansion limit is your own creativity and imagination.
also plays a key role in the development of the At the time of writing, stock of the NanoPi
streamer. The only real
NanoPi, with a 36-pin GPIO also included for NEO was plentiful, but due to initial press
limit is your own creativity good measure. We should also add that the feedback, it’s expected that stock will soon
GPIO included here also includes UART, SPI, I2C dwindle. You can order your own NanoPi NEO
and imagination.
and IO, all integral part of a developer’s arsenal. over at www.friendlyarm.com.
8
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NVIDIA TOP FIVE
Lesser-
known Linux
distributions
1 Scientifi c Linux
Scientifi c Linux is defi nitely for those who have
spent years learning the ins and outs of the
wonderful world of Linux distributions. It includes
a variety of packages; including Cluster Suite,
Nvidia unveils big FUSE and Squashfs, which all work in tandem
with one another in order to create a seamless
user experience.
changes in graphic 2 Yellow Dog
Although Yellow Dog was originally released for
use on early Apple computers, under its current
driver update
management, it has been transformed in to a
Big fi xes are plentiful in Nvidia’s latest update
It’s been just over a month since we last saw tool. Based on user responses, it seems that
the 367.27 video driver update from Nvidia, both of these crashes have been rectifi ed in the
which first introduced support for its costly, update. Another small bug that’s been squashed high-performance distribution that doesn’t have a
steep learning curve.
but impressive, GeForce 1080 and GTK 1070 addresses the system crash when the peer-to-
graphics cards on the Linux kernel-based peer mapping tool was enabled, but we’ve yet to 3 Ubuntu Studio
operating system. But that short timeframe see the effectiveness of this in action.
hasn’t stopped it releasing the next milestone As well as bug fi xing, the one key inclusion Whether you’re into music, video or photography,
update, 367.35. In its current form, the update of the 367.35 update comes in the form of Ubuntu Studio is the ideal choice for media
is available for all UNIX-like operating systems, new support for VDPAU (Video Decode and enthusiasts. It comes packed with an array of
media-friendly apps and a host of helpful editing
including Solaris, FreeBSD and GNU/Linux, Presentation API for UNIX). For end users, it will
tools to boot.
although wider support is expected to appear in enable their Nvidia graphics card to decode 8K
the coming weeks. encoded video streams, a massive step for media 4 Parted Magic
The main thrust of this update is to provide consumption for Linux users. It’s expected that
fi xes and tweaks to an array of issues fi rst the feature will be fl eshed out over the coming Parted Magic is half distro, half program. It
includes all the necessary tools you could
highlighted in the previous version. One of the months, as Nvidia explores the true capabilities
possibly need to fi x broken partitions, and
key fi xes is the stopping of console corruption, of VDPAU. Last but not least, the overall buffer
is especially useful when trying to diagnose
when users would resume their activity after write performance has been massively improved something that simply won’t boot.
using the suspend feature, something that in the update. The implementation of DRM Dumb
would often lead to additional errors appearing Buffers should make the buffer write process 5 Bodhi Linux
on other areas of the desktop. Another big that little bit more manageable.
Perhaps the best known of these is Bodhi Linux, a
hole that’s been plugged is within the nvidia- Users can download Nvidia 367.35 for their 65
unique distribution in terms of both its looks and
settings confi guration tool. Previously, there or 320bit system over at nvidia.com, or directly usability. It includes a fantastic window manager
was a frequent crash on displays using 8 or 15- through the Nvidia desktop client installed on system, which is handy to have when organising
bit colour depths when using the confi guration their machines. your desktop.
www.linuxuser.co.uk 9
008-011_LUD169.indd 9 10/08/2016 15:14
OpenSource
Your source of Linux news & views
SKYPE
Alpha release
of Skype
for Linux is
fi nally here
An all-new Linux client
brings voice calls back
to your machine
It’s been a while since we’ve seen a release
from Skype for its Linux client, so much so
that the old client was stuck on version 4.3,
Above Microsoft has ditched the old Skype client and launched something new
whereas the Windows version is on version 7.
Instead of providing a new update for the current currently involved. Behind the scenes, Skype of Skype for Linux, but a more wide-spread
client, Microsoft has launched an all-new client is working on a big overhaul of its network release will be taking place soon.
for Linux users to enjoy. infrastructure, to help improve connection Also new from Skype is a second client
Due to the client currently being in its performance and keep server problems to an for Linux users to get excited about. Skype
alpha stage, there are numerous restrictions absolute minimum. There’s also restrictions Web Client will work on both Chrome on
on the type of calls that can be made, with only Linux machines, as well as any Chromebooks
Instead of providing a
voice calls working at the time of writing. And running the Chrome OS. By and large, the core
new update for the current for those hoping to use the old version of Skype capabilities of the program are the same as
in the meantime, it won’t work in tandem with the desktop version, and it runs on Chrome’s
client, Microsoft has
the new client, so be warned. WebRTC to provide a plugin-free Skype
launched an all-new client In its current state, only users of the current experience. Users should head over to Skype.
OS X, Windows or Android version of Skype will com for download links and installation guides
for Linux users to enjoy
be able to get their hands on the alpha release to both of these clients.
OPEN SOURCE
Toyota and others join Open Invention Network
Established back in 1995 in a bid to defend self-driving cars, many of which are embracing stop any internal battles between members.
Linux against intellectual property attacks, the open-source ethos, patent protection is at In return, all members have a say on how
the Open Invention Network was spearheaded an all-time high. Also joining Toyota are Ford the Open Invention Network handles its
by an array of leading technology brands. Motor, Kia and Hyundai. businesses and enforces its shared patent
While the likes of Red Hat, Sony, IBM and Philips In this case, the same rules apply as any pool. Considering the potential cost of patent
are all credited with launching the alliance, it has other company joining the network; members enforcement and litigation, the alliance has
grown dramatically to cover many areas outside need to agree that they’ll share their patents proven to save many companies a lot of money
of core technology companies. with the OIN License Agreement, arguably to and headaches.
One of the last remaining areas not to In total, the Open Invention Network boasts
get heavily involved with the Open Invention The Open Invention over 2000 members, covering everything from
Network has been the automotive industry, mobile, IoT, embedded technologies, and now
Network handles its
but that has just changed for the better. automotive. Following on from the recent rise in
Toyota has led a wave of leading automotive businesses and enforces members, rumours are hinting that Microsoft
manufacturers to join the network and their may soon be jumping on board with the Open
its shared patent pool
reasons for doing so are clear. With the rise of Invention Network, but nothing is confi rmed.
10
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