The Mag Pi Issue 1 En

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ISSUE 01 MAY 2012

A Magazine for Raspberry Pi Users

• RacyPy
• Debian
• Scratch
• Python

Introducing...
The
Raspberry Pi
A new breed
of computer

NO MORE
APPLES
FOR
TEACHER!

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wass crreeaatteedd uusiing aa Rasppbberryy PPi coomppuutteerr.
FFrroontt CCovverr aanndd FFeeddbbacckk IIm
mageess ccrreeated uussiinngg hhtttpp:://pphottoffunnia.ccom

Over the coming issues, The MagPi will
explore the exciting things that can be
done with this very special computer.
We will introduce you to the various
Raspberry Pi operating systems, how to
program in a range of languages, and
start your own interesting projects. We
aim to help experts and beginners get the
most out of the Raspberry Pi hardware
and more importantly help build a fun a
friendly community for everyone to get
involved with.

If you like your apples to be white
and shiny, your apricots made from
silicon, and you'd rather talk to
your blackberries, then you may be
in for a treat...

Interest in the Raspberry Pi is already
incredible, and demand has far exceeded
expectations. IT professionals, electronics
experts and newcomers are all eager to get
their hands on the small device which
everybody agrees 'is going to be huge'.

The Raspberry Pi computer is the size of a
credit card, completely silent and costs under

Article by Jaseman & Meltwater

£30. The operating system runs from an SD
flash card, allowing its personality to instantly
be switched by swapping cards. Its potential
uses are staggering, and as yet, not fully
explored, but it has already been tested as a
multimedia player with streaming capabilities,
a games machine, an internet browser and a
hardware development board. It is intended to
be used as an educational device for people of
all ages and skill levels.

Lucky Element 1 4 Road Test Prize Winner
'GizmoB73' unboxed this late 'R&D' prototype.

Contents
Affordable Computing
The Fall Of Programming
The Pioneers
Hardware Development
Skutter
RacyPy LiveCD & Virtual Machine

P.04
P.05
P.06
P.09
P.10
P.12

Debian VirtualBox
Programming
The Scratch Patch
The Python Pit
Feedback
Web Links & Credits

P.16
P.18
P.20
P.23
P.30
P.32

The Dawn Of
Affordable
Computing
The ZX81 and Spectrum by Sinclair
Research, were among the first
affordable home computers available
during the early 1980's.
Although these 8bit computers were
crude by today's standards, they gave
ordinary people the opportunity to
write computer programs and games.
The BBC Acorn computer was
backed by the British Government
for use in education and subsidies
were granted to schools. These
computers were a little too expensive
for most families to have at home.
The 'Electron' was Acorn's attempt at
addressing the price issue. They sold
a number of units, however despite
being more powerful on the hardware
side, the range of game titles was
significantly smaller than rivals
Sinclair and Commodore.

The Fall Of
Programming

Home computer users were becoming less
interested in writing their own programs.
Slicklooking, professionally made games that
were coming out of software publishing
companies were compelling.
Ocean Software for
example, boasted an
impressive library of
hit game titles such as
'Daley
Thompson's
Decathlon',
'Chase
HQ' and 'New Zealand
Story'.
The trend of moving away from programming
followed within the education sector. Early
software packages like Wordstar, and Lotus 123
were difficult to use before the days of the
graphical interface, but typing skills, word
processing, spreadsheet and database training
continued to be the focus. Programming was seen
as a very specialist and niche area of study.

the Raspberry Pi Foundation Trustees

The Pioneers
The story of how the Raspberry Pi computer came to be.

Cambridge and Beyond
Cambridge University attendees have played a major role in the development of
computers in Britain. The story of how these individuals have branched out into various
organisations such as ARM Holdings plc, Acorn, Sinclair Research, Element 1 4,
Broadcom and the Raspberry Pi Foundation is a complicated one.

To understand the links between all of these
companies and organisations is extrememly
difficult, due to many mergers, aquisitions,
dismemberments,
shareholdings,
employment movements and so forth, and
many a journalist has been beaten trying to
unravel exactly who did what, and now who
owns it.

Initially the plan was to build a simple
microcontroller-based computer that booted
straight into a python interpreter prompt
(the Pi in the Raspberry Pi name was a
reference to the Python programming
language).

This cheap device was intended to be used
to promote and invigorate the next
What we do know is that the Raspberry Pi generation of programmers and developers.
project began in 2006. There was a common
desire amongst certain individuals to
recapture a sense of the pioneering spirit of
computing that came during the 1980s,
When affordable personal computers
became available to the average hobbyist or
budding computer enthusiast. There was a
growing concern about the diminishing
interest in computer science and an opinion
that the ICT curriculum had become too
focused upon word processing, spreadsheets
Early microcontroller-based circuit board
and databases.
6

Due to the cost of producing a working
system with networking capabilities, device
drivers, etc. built into the interpreter, it was
decided that it would be easier to use an
already freely available operating system
(Linux). Using Linux would also allow
flexibility in the choice of programming
languages and other software that could be
used.
The option of using a 'System on a Chip'
(SoC) became preferable to a
microcontroller computer. Broadcom had
developed a range of ARM processors for
use in smartphones.

The first prototype boards were the size of a
USB memory stick, with 1 USB port at one
end and a HDMI video output at the other
end. These boards used microSD memory
cards to store the Linux operating system.
The boards were too small to accomodate a
network port, GPIO header, composite video
and analogue audio outputs, which would
mean that they were unsuitable as hardware
development boards.

USB Stick sized early version of the Raspberry Pi

Broadcom employee Eben Upton and other
luminaries such as David Braben (Famed
writer of the BBC Micro games 'Elite' and
'Frontier'), Jack Lang, Pete Lomas,
Professor Alan Mycroft and Dr Robert
Mullins set up a charity called 'The
Raspberry Pi Foundation'. The idea they had
in mind was to design a SoC board
populated with a Broadcom ARM11
processor chip, which could be produced
and sold at a very inviting price, to a
potential new generation of computer
science engineers.

It was decided that a credit-card sized
board would be sufficient, and the
Raspberry Pi Foundation set about
designing the board layout and working
with the Linux community to develop and
refine a number of Linux operating system
distributions that would work well with the
700MHz ARM1176JZF-S processor. The
initial design had an SD card reader fitted
to the underside of the printed circuit
board (PCB), however the first prototype
card readers protruded slightly outside the
credit card shape.
continued over page...

Co-founder Eben Upton displays one of the first Alpha Boards

In August 2011, fifty alpha boards were
produced. The SD card reader had been
repositioned to be flush with the edge of
the card.
By December 2011, beta boards of the
Raspberry Pi were able to demonstrate Full
HD 1080p video playback and a ported
version of the Quake 3 game, using the
onboard Videocore IV graphics processing
unit (GPU).

Notably the beta boards were fitted with
micro-usb power connectors. This meant
that it would be possible to use the
commonly found phone chargers to power
the boards.
In January, The Raspberry Pi Foundation
auctioned some of their prototype
Raspberry Pi boards on Ebay and
announced that the first 10,000 Raspberry
Pi computers were being manufactured in
China. They would be sold through
industrial components suppliers 'RS
Components International' and 'Premier
Farnell' with additional design engineer
community support provided through
'Element 14'.
After a few setbacks, the first Raspberry Pi
boards were available for pre-order. The
official launch was at 6am UTC on the
29th of February 2012.

Raspberry Pi beta board

Article by Jaseman

H a r d wa r e D e ve l o p m e n t a n d R o b o t i c s
Gert van Loo has developed a General
Purpose Input/Output (GPIO) expansion
board for the Raspberry Pi, called the
Gertboard. The board is able to control
flashing light-emitting diodes (LEDs),
and connect to servo motors, sensors
and other electronic components.

Enthusiast 'Bodge N Hackitt' is planning
to connect a robotic arm to the USB port
and GPIO header of a Raspberry Pi.
The first part of his series of articles
entitled 'Skutter' can be found on pages
1 0-1 1 .

Gertboard & Motor

OWI USB Robotic Arm Kit

Over the coming months we will be
following these and many other
interesting home-grown projects.

SKUTTER
By Bodge N Hackitt

In these articles I will be describing some
experiments into controlling real world
applications using various aspects of the
Raspberry Pi computer.
I was inspired to start this project when a
member of the Raspberry Pi forum brought to
my attention a low cost robotic arm kit that
could be controlled via a computer's USB port.
The arm reminded me of something called a
"skutter" from one of my favourite TV shows,
Red Dwarf (pictured right) that was on when I
was still growing up. I thought that, as the
Raspberry Pi is so small, has such low power
requirements and is still so useful as a
computer that I could easily combine the robot
arm with a kind of motorised base and have
the whole thing run from batteries and
powered by a Raspberry Pi which would act
as the Skutter's 'brain'
It seemed to me that this would make a fun
kind of project which could even have some
serious applications. Imagine if you could
make an intelligent robot that was able to run
about on its wheels and manipulate things in
the real world with its robotic arm. Yes, it could
be fun just in its own sense but also it could be
of tremendous use for people with disabilities.
It might even one day be useful as a kind of
fix-it bot that could access small spaces where
people would find it difficult or dangerous to
get to.
In order to accomplish this, the Raspberry Pi
has two interfaces which will allow us access
to control stuff. The first of these is a kind of
standard interface which almost all modern
computers have built in. It's called a "USB" or
Universal Serial Bus.

I will explain how some elements of USB work
in the next article, but it is worth noting here
that this little port that we take for granted is
extremely complicated. Fortunately there are
some things which will make our work with this
easier.
The second of these interfaces on the
Raspberry Pi is called the GPIO which stands
for General Purpose Input (and) Output. This
part of the Raspberry Pi promises to allow the
user to easily control all manner of devices but
at the time of writing this article the Raspberry
Pi is not available.
This means that the first of these experiments
will be carried out using a "virtual" Raspberry
Pi running on a PC (This is not strictly true, a
proper virtual RasPi would involve

programming a simulation of the ARM
processor, its memory, storage and all its
other associated parts. My "virtual" Raspberry
Pi is actually just a minimal installation of
Debian-Linux (the operating system) that's
running on a program called Oracle Virtual
Box. Luckily this set up does give me access
to the USB port and this should work exactly
the same in this virtual implementation as it
would on the real thing. (Sadly, at the moment
we can't try things that would use the GPIO as
there is currently no straightforward way of
making a virtual Raspberry Pi with a virtual
GPIO header).
The robotic arm kit called the "OWI Edge" is
currently available from Maplin electronics and
it uses a simple USB interface to control it.
This kit is sold with a CD ROM with software
that will allow you to control it from a Windows
PC. The software allows you to remote control
the robot arm or to make a sequence of
instructions that controls it by setting the time
and direction that each joint should move. The
design of this robot and software is very
limited. The software only allows for the most
basic of programming and movement and the
arm itself has no feedback. This means that,
as it is we have no way of knowing what the
arm is doing other than by looking at it
ourselves.

As this project progresses we will cover some
ways of adding simple " feedback" to our
robotic arm so that it will know where each
arm part is in the space around it (its
environment).
We will also investigate some more advanced
methods of giving our robot a kind of sense of
sight by using "sonar" and we will consider
some further possible applications of machine
vision using cameras.
When the actual Raspberry Pi computer
becomes available we will be able to start to
put things together properly and begin to
construct our motorised base.
In the next article I will cover methods of
controlling the robotic arm via the USB by
writing instructions in
the Python
programming language. Looking forward to
seeing some of you again then.

Article by Bodge N Hackitt

A truly useful robot needs to know itself where
it is in space. In theory we should be able to
say to it "Get the object over there" and the
robot will know I am " here" and I need to be
" there" To get to " there" I must move by " this"
much and in " that" direction.
To make this simple robotic arm into a more
useful device we will need to do some
'hacking' and make some modifications.

A Tasty Bit Of RacyPy
Why not have a play with RacyPy and jump into the world of Linux
and programming? RacyPy which uses P uppy, a lightweight Linux
distribution, which can be used to try out Linux on any PC without
even installing it. This is packaged with a range of tools ready to go,
so you are ready to try the tutorials later in this magazine.

What is RacyPy?

Get Ready!

RacyPy, is a pre-packaged cd image First, obtain the iso image file:
which when "booted" (run from power
RacyPy4_1 .iso (507Mb)
up) will load a graphical desktop similar
http://goo.gl/nGy8u
to a MS Windows or Apple Mac
computer.
Depending on the method, you’ll need:
The RacyPy image is setup as a “Live Live CD Blank CDR & CD/DVD
CD” which means it loads directly to
Writer
memory and nothing is installed.
Virtual
hard-drive space
RacyPy comes with a range of software Machine 940MB
This includes:
ready to run, such as:
~300MB for the Virtual Machine

software when installed
384MB for the iso file
256MB for temporary RAM space
(only needed when running)

AbiWord - word processing
Gnumeric - spreadsheet

SeaMonkey - web-browsing

If you intend on keeping your settings
Python 2.7.2 and 3.1 .4 - program- (which can then be loaded each time),
ming
then it is recommended you have a USB
flash memory stick of at least 1 GB or
mtPaint - graphic editing
more.
MPlayer/Ogle/Pmusic - video/
DVD/music playback
Geany/Vim - programming editors
Plus many other useful utilities. If you
decide to use RacyPy more than once
you can also setup a USB Memory
Device to store your user data on, this
will also allow you to install any
additional programs which will be loaded
every time you reload it.
Thanks to TeamPython and antiloquax for permission to use RacyPy!

Universal USB Installer
http://www.pendrivelinux.com

If you don't have a CD/DVD drive on
your system it is also possible to boot
and run Linux from a USB memory
device (1 GB or more).
Follow

the

guide
from
http://goo.gl/S4VTI but instead of
"Lucid Puppy" select "Racy Puppy".
Then press "browse" to RacyPy4_1 .iso
you downloaded above. If you don't
see it, try ensure you have named it
with “racy” at the start of the filename.

LiveCD Boot
The simplest way to use this image is
to "burn" the "image" to a CD. You can
use your own software or you can use a
free program called ImgBurn, which will
ensure the CD is written correctly to
allow it to boot.

ImgBurn - http://www.imgburn.com
Once you have
installed
the
software, you
can “right click”
on the iso file and select “Burn using
ImgBurn”. Alternatively, run the
program and select, “Write Image
File To Disc” and select the iso file
(File ->Browse for a source file…).

Virtual Machine
A really useful way to try out Linux
is to use a virtual machine (VM). A
VM is simply a simulated computer
which runs on top of whatever
operating system you are using.
This means you can run this virtual
computer in a window alongside
your other windows, and everything
to do with it is contained within a
few files separate to your normal
operating system. When you are
done, you can simply remove them!
To run RacyPy we recommend using
VMPlayer, which can be obtained
from http://www.vmware.com or
directly from http://goo.gl/8oKED.

Insert your blank CDR
into your CD writer
drive and start the write
process, by pressing
the write button.
Once you have a CD, you need to
ensure your system will "boot" from it
(use the CD to start up instead of your
normal operating system).
If your computer doesn't do this
automatically, often there is a
particular key you can press (F2, F8
etc) to select booting from an optical
device. Each computer is slightly
different so pay particular attention to
any messages which flash up when
you first switch on your computer.

1 . Once you have installed VMPlayer,
open the program and select "Create
a New Virtual Machine.
2. Select "I will install the operating
system later".
3. Select "Other" and "Other" for the
Guest Operating System. We do not
need any specific features, so generic
options should be fine.
continued over the page...

Got a taste for more?
You can install and try out Debian (the
official Raspberry Pi distribution), later
on in this issue.

4. Name your Virtual Machine and
locate it where you want to. It'll only use
up ~2MB of space when not in use.
However, when it is running it'll create
a temporary RAM file (default is
256MB). If you "suspend" the VM
(pause it so you can return to it in its
current state) it'll keep that file,
otherwise it will be removed when you
"power off" the VM.

5. Next "Specify Disk Capacity", we
don’t need a virtual disk, but the wizard
asks anyway. Select 1 GB size, and to
split the drive, but since we don’t use it,
it won’t take any space up.

7. Next we will virtually insert our
RacyPy image into our virtual CD/DVD
drive. Right click on your new virtual
machine and select "Virtual Machine
Settings...". Select "CD/DVD (IDE)",
then "Use ISO image file" and browse
to where you have downloaded your
RacyPy4_1 .iso image (ensure you keep
it where you won't move it. i.e. in the
VMs directory). Ensure this is set to
“Connect at power on”.

8. Finally, to allow Puppy to sit
comfortably within a window, we can
force the virtual screen to be a fixed
size, ideally slightly smaller than the
monitor you are using. So, for a
1 280x1 024 monitor, 1 024x768 is fine.

Now you can run the new VM, and
boot into Puppy!!

6. Finally confirm you want to create
the new VM, by pressing Finish.
However, don't run it yet, we have a
few more tweaks to make.

VMPlayer Tips:
1 . To control the VM, click in the
window to capture your mouse and
keyboard, then press Ctrl+Alt to
release.
2. If you use a USB Flash Memory
to store your user data, next time
you run the VM it will remind you to
re-attach your key if it is missing!

First Boot
When you boot for the first time, you will
be able to configure your setup. Puppy
allows you to store all your user data
conveniently on a USB memory device
so it is available next time you boot
(regardless of which machine you are
using).

To Keep Your Data
After booting and configuring your setup,
1 . Select "Shutdown" and "Power-off
computer" from the bottom "Menu"
button.
2. You will be prompted by the "First
shutdown: save session" window. As
recommended, choose to "SAVE TO
FILE".
3. We will select the defaults (carefully
read the info there for other options).

First shutdown: Default Action
ask fido
get ready

choose filesystem
save-file name
encryption
size save-file
sanity check

Select "administrator"
Plug the USB memory
device in*
Select "ext2"
Leave blank
Select NORMAL
Select 51 2MB**
Should match below!

NOTES:
*If using a VM, you may need to click
on the device icon at the bottom of
the window (next to VMWare logo). If
successful you will see the following
icon appear on the desktop.
**The remaining space can then be accessed
and used by both Linux and Windows.
***On the 1 st boot after this, you may be
asked about adding "BootManager:SFS files".
Press ok for now, we will cover this another
time.

Optional "Pets"

Since this is based on Puppy Linux,
there are many packages which are
extra easy to install called "pet" files.
The files contain everything to install
and setup the program.

Installing Pets

Either download the "pet" file directly
within RacyPy or put the file on your
USB memory device. Click on the file
and confirm you want to install. The
"Woof" package manager will tell you
when it is installed and where in the
menu to find it (i.e. Scratch will be put
under "Utilities").
E.g. Scratch as used in this mag:
Scratch.pet - http://goo.gl/ZPllt (33Mb)

4. After the 2fs file is written it may
prompt "copy .sfs from CD", this is
optional (it will use 379MB extra on the
USB memory device).
5. The next time you boot with the USB
memory device attached, it will load up
your settings and programs from your
last session.***

More information on using RacyPy, how to
now get a RacyPy distribution for the
Raspberry Pi plus guides on getting started
programming with Python and Scratch visit:

http://raspberrypy.tumblr.com

Article by meltwater
15

A step-by-step guide to creating a virtual
machine of the 'Debian Linux' operating
system to run on your Windows PC.
An 'Operating System' (OS) is a set of
instructions that help a computer to
understand how to control the connected
hardware devices.
The 'Boot Sequence' is a list of events that
begins when you power up your computer.
A state of readiness is usually indicated when
all the screen activity has stopped and you are
confronted with a logon prompt or graphical
user interface (GUI). In this example the GUI
is called 'LXDE' - Lightweight X1 1 Desktop
Environment.

While waiting for your
Raspberry Pi, why not try
the Linux Debian OS?
Download the Debian LiveCD ISO
file:
For Intel Processors (770 MB): http://goo.gl/Hvkbe
For AMD Processors (770 MB): http://goo.gl/fkkLC

Then download and install Oracle
VM VirtualBox:
For 'Windows Hosts' (92 MB):

Creating the Virtual Machine
1 . Start Oracle VM VirtualBox

2. Click 'New'
3. Click 'Next' to start the 'New Virtual Machine Wizard'

6. Untick Start-up Disk.
7. Click 'Continue' at the warning

4. Name: Debian O.S.: Linux Version: Debian

8. Click 'Create'
5. Memory: 256 MB

http://goo.gl/gLmjf

1 4. Click OK to leave the Settings screen.

9. In the right hand column of the VirtualBox Manager,
click on the word 'Storage'
1 5. Click 'Start' to boot the virtual machine

1 0. Under IDE Controller, click on the CD icon (Empty)
1 1 . Tick Live CD/DVD and click the CD icon next to
'CD/DVD Drive:' (Under Attributes)

1 6. Press ENTER to choose 'Live' option
Wait a moment while Debian boots into the LXDE
graphical interface. More to follow in issue 2.

1 2. Click 'Choose a Virtual CD/DVD disk file...'

1 3. Browse for the downloaded Debian .iso file and
click 'Open'

Article by Jaseman

>Programming
Computer
programming
or
'coding' is a method of getting a
computer to perform tasks, such
as displaying and processing
information, creating games and
applications
or
controlling
devices, motors or robots.
The computer can interpret our
commands through programming
languages, which help to make the
processes of instructing the computer
easier.
When we 'run' a computer program,
the computer starts to carry out our
instructions step by step and reacts to
'events'. We can tell the program how
it should deal with certain events. For
example, your program might be
instructed to sense events such as a
18

certain key being pressed on the
keyboard, a click of the mouse on a
button, and how it should react to
these events.
The MagPi will show you how to get
started writing your own programs and
games, and providing examples and
tutorials.
'The Scratch Patch' and 'The Python
Pit' are the first programming sections
of the magazine (See pages 20
onwards). We will be adding to this as
things progress.

Article by Jaseman
All logos and trademarks remain the property of their respective owners.

'Scratch is a programming language that
makes it easy to create your own interactive
stories, animations, games, music, and art'

'Python is a remarkably powerful
dynamic programming language that
is used in a wide variety of application
domains.'

'Pygame is a set of Python modules
designed for writing games. Pygame
adds functionality on top of the
excellent SDL library. This allows you
to create fully featured games and
multimedia programs in the python
language.'

'A geometry package providing for
both graphical and algebraic input..'

'KidsRuby makes it fun and easy to
learn how to program.'

'JavaScript is a prototype-based
scripting language that is dynamic,
weakly typed and has first-class
functions. It is a multi-paradigm
language, supporting object-oriented,
imperative,
and
functional
programming styles.'

'HyperText Markup Language is the
main markup language for web
pages.'

There
are
many
other
programming
languages
available to try. We will try to
introduce some of them. Feel
free to submit your own
programming articles.
19

Here at The MagPi, we highly recommend you to try out 'Scratch' - An easy to use
programming language for beginners. If you don't already have Scratch, you can
download it from the following website:
http://info.scratch.mit.edu/Scratch_1.4_Download
Once you have it installed and running, the best way to get started is to click on the
Help pull-down and take a look at the Help Page and Help Screens. Most of the
information you will need is already there. Spend some time familiarizing yourself with
the scratch interface - It is very intuitive. Then try our Dizzy Cat / Crazy Drum tutorial on
the following pages.

Dizzy Cat / Crazy Drums

Here is a rather silly little Scratch program
for you to try:
1. Open Scratch

5. Click on 'Motion' and drag the 'turn 15
degrees' block into the middle of the
'forever' block.

2. Click on the Scratch Cat Sprite 1

6. Click the green flag to start running the
script, and see Scratch Cat spinning.
3. Click on Control and drag the 'when flag
clicked' block to the Scripts area.
7. Click on Looks and drag the 'change size
by 10' block under the 'turn 15 degrees'
block (Also inside the 'forever' block. Watch
how the cat grows.
4. Drag the 'forever' block to the scripts
area so that it locks in place under the
'when flag clicked' block.

8. Change the '15' in 'turn 15 degrees' to '5' and change the '10' in change size by 10'
to '-1'. See how the cat starts spinning in
the other direction and slowly starts to
shrink.

9. Make the cat grow again by changing the
value o f 'change size by' to '1'.
continued over page...

11. Keep adding more and more drums and
change the number of each one so that the
numbers go from 35 all the way up to 81.
Listen to the different sounds each drum
makes. As the scripts area fills up, you will
have to use the scroll bar to the right to
scroll up and down.

10. Click on Sound and drag the 'play drum
48 for 0.2 beats' into the 'forever' block.
Then change the value of play drum from 48
to 35.
12. Drag the 'change tempo by 20' block
into the 'forever' block. Wait and listen as
the drums get faster and faster. When you
can't take it anymore, change the value of
'change tempo by' to -20. After a little while,
the drum tempo will slow down again Phew!

13. Press the red spot which is next to the
green flag to stop the terrible noise!
Poor cat!

By Jaseman

Here at the Python Pit, you will find Python and
Pygame programs to type in. Each month we will
bring you examples that will help to demonstrate
some of the commands and programming methods
to get you started writing your own code.
All of the programs are tested before the magazine
goes live, and will have a stamp underneath
showing which operating system and language
versions were used for the testing.

Note: The examples in this issue are written for Python 3. They will work on older versions by making a
change to all the print commands: Change print ("TEXT") to print "TEXT" remove the ( ) brackets.
# PUTTING TEXT ONTO THE SCREEN
# By Jaseman 23rd April 2012

print("*** Welcome to The Python Pit! ***")
print() # A line space
print("Brought to you by The MagPi")

The # hash symbol means 'comment'
Python will ignore anything that is written
after the hash - it is a way to add your own
headings, notes or reminders to the
program.