Easy AMOS User Guide

434 Pages·1992·13.3 MB·English

by  Mel Croucher

Follow the instructions in Chapter 1
then write your Easy AMOS Registration
Number in this box
! _________- -'
I-I_ _. ....
when it appears on your screen. Thank you.
DO NOT ATIEMPT
TO BACK UP YOUR
EASY AMOS MASTER
DISCS!
READ CHAPTER 1
FIRST.
F-
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l....::J
by
Franyois Lionet
© Europress Software Ltd. 1992
Software design and programming Fran90is lionet
Manuals design and author Mel Croucher
Manual layout and typesetting Kate Cameron-Daum
Manual illustrations Robin Evans
No material may be reproduced in whole or part without written permission from
Europress Software. While every care has been taken to ensure this product is correct,
the Publishers will not be held legally responsible for any errors or omissions in the
Manual or software.
ISBN# 9 7818 720 84527
e
urOPRESS
": __ g ____ r,_:t: __ ~ __ I\, __I {_ __ "
Europress Software,
Europa House,
Adlington Park,
Macclesfield,
Cheshire, SK10 4NP.

'AlIo! 'AlIo! Reading this book and using this software can change
your life, like computers changed mine! Before computers, I was
learning the life of a vet, how to inject vaccine and clean cow's foot.
Then I did a big mistake, I bought me some old fashion computer. It
was fantastic. My programming passion grew. By the time I
graduate, I did not practice as vet at all! And here I am, comfortably
sat with my keyboard, writing an intro for Easy AMOS!
So, I warn you, my friend, you may discover a passion for
programming lying inside you, and this passion has a lot more
chance to grow with a computer like Amiga and a program like Easy
AMOS. What you have in your hand is the result of ten years
learning. Ten years spent with ugly technical manuals, ugly tools,
ugly syntax, ugly programming. But now I have put in this product
all I wish I had before. With Easy AMOS, I expect you to become a
programmer in a few weeks. Truly. Easy AMOS is more than a
learning tool. It is a full language with 350 commands, full help
features, examples, programs, musics, graphiCS, datas. We have
crammed in your discs hundreds of hours of entertainment.
So stop reading all this intro. Easy AMOS is your entry ticket to the
private club of programmers. Hope to seeyournameina commercial
game very soon.
Fran<;ois Uonet
Easy AMOS programmer
This Guide Book is the one I needed when I began programming,
back in 1966. I could have let Easy AMOS lead me by the hand for
a bitofinstantsatisfaction. I could have flicked through the Glossary
and begun to understand what all the jargon meant. But in those
days computer manuals were less friendly than rat poison and not
as effective. If you think I've devoted too much space in this book
on the needs of absolute beginners and indulging in cartoons, you're
probably right. Enjoy it anyway, because I reckon Easy AMOS is a
wonderful system. If only it had been around when I was you.,
Mel Croucher
Easy AMOS book author
iii
I cut my computing teeth in 1982 at the age of 22, on an Atari 400.
There was very little entertainment software then, so I spent a lot of
time trying to program. The manuals and books I bought weren't
very good, but I kept atit and found programming an absolute thrill.
I got a genuine kick out of writing games and practical programs
over the following year or two, and my hobby introduced me to
many new friends.
The Easy AMOS team members have brought together their
combined experiences to produce the ideal package which would
have excited, stimulated and encouraged them to learn to program.
I am sure you will get a lot out of Easy AMOS. You will have a lot
of fun and feel a tremendous sense of achievement as you work your
way through this manual. Take it at your own pace and I can
guarantee that you will amaze yourself! Happy programming.
ChriS Payne.
Managing Director. Europress Software
I spent most of my teens learning to program on an antique 48K
Atari-400. Countless hours were spent trying to harness my
computer's power, but only short snippets from magazines and
highly technical manuals were available to me. Perseverance paid
off, and after years of studying and lots of head scratching I managed
to master the beast. This taught me a great deal, but it would have
been a much easier journey if a detailed manual had been available
to explain everything. So knowing how difficult it can be to learn
such concepts, please believe me when I tell you you've got it easy!
The Amiga 500 may be the most powerful home computer to date,
but all the hassle of controlling it is handled by Easy AMOS.
Take your time over learning Easy AMOS. Some concepts will take
longer to understand than others, but eventually all the pieces will
fit into place and you will become a competent programmer. Who
knows, you may be the next Fran<;ois for Europress!
Richard Vanner
Projects Manager. Europress SOftware
iv
Before testing Easy AMOS, I had only ever used my Amiga for playing games.
I was a total beginner when it came to programming and an ideal candidate
to be a guinea pig. I was told that the package would live up to its name and
be easy. Not only was it easy and completely painless, it was also FUN! If I
can understand Easy AMOS I'm sure that anyone can! As I was testing the
Chapters out of order I tried to make sure that each stood on its own, but if you
do find yourself struggling over a particular Chapter don't worry, you can
always go on to other Chapters and come back to it later. Whatever you do,
make sure you try the "Sound" Chapter: it was amazing when I found out that
my computer could talk to me! And even more amazing when I reached the
end. I felt I understood how to program! There can never have been an easier
way to learn. I hope you enjoy using Easy AMOS as much as I enjoyed testing
it.
Ian McFegan
:ompany Accountant, Europress Software
"Contents are rich, and rich
enough."
(William Shakespeare, 1604)
v
Contents Contents
1: INTRODUCTION 1 6: TEXT 79
hello 2 the character set 80
computer programs 3 using text 83
care of discs 3 text coordinates 84
how to install Easy AMOS 4 moving text 85
let's go! 14 the text cursor 87
your first program 16 text style 90
fonts 91
2: FIRST STEPS 19
keywords 23 7: WORKING WITH THE
saving a program 26 KEYBOARD 95
deleting a program 27 moving the text cursor 96
loading a program 29 setting tabs 97
the file selector 30 checking for a keypress 97
the edit screen 32 the Easy AMOS Typing Tutor 100
direct mode 34 keyboard short-cuts 101
3: UP AND RUNNING 37 8: GRAPHICS 103
the Easy AMOS Help System 38 graphic coordinates 104
separating commands 40 drawing lines 105
Rem statements 41 drawing shapes 108
the Default Menu 42 colour 110
the System Menu 42 filled shapes 114
the Search Menu 42 flashing 120
the Blocks Menu 44 rainbows 121
graphical text 125
4: THE BARE BONES 47
strings 48 9: BOBS 127
variables 49 the main menu 131
arrays 53 disc operations 135
functions 54 bank operations 137
the grabber 139
5: LOGIC 59 hot spots 141
labels 60 palette colours 142
loops 66 screen resolutions 144
conditional loops 67 animation 145
numbered loops 68 drawing tools 148
steps 69 using Bobs 153
subroutines 69
conditional jumps 71 10: UNDERSTANDING
procedures 72 SCREENS 167
nesting 77 the default screen 169
defining screens 169
IFF screens 171
vi
Contents
Contents
hiding and showing screens 173 16: PERIPHERALS, DRIVES
screen priority 173 AND DISCS 265
moving screens 175
joysticks 266
converting coordinates 178
the mouse 267
11: USING SCREENS 181 printers 271
switching screens 182 disc drives 272
copying screens 185 listing fi1es 273
selecting and naming files 279
scr<..>en colours 188
fade effects 189 running programs from disc 280
zooming 192 the Easy AMOS Disc Editor 283
screen zones 192 17: MEMORY 293
screen blocks 195
addresses 295
compacting screen memory 197
available memory 295
EHBmode 200
allocating memory 296
HAM mode 200 saving memory 298
12: SOUND 203 memory hanks 298
sound effects 204 machine code 302
synthetic speech 205 18: DEBUGGING ERRORS 309
music 207 bugs 310
samples 214
the Sample Bank Maker 219 shpeolptt ing mistakes 331100
waveforms 223
trapping errors 311
13:MATHS 229 error messages 315
arithmetic 230 19: THE EASY AMOS TUTOR 327
floating point numbers 234 the graduation challenge 328
trigonometry 235
calling the tutor 329
random numbers 238 the tutor screen 330
14: CREATING A GAME 239 the control keypad 331
single-player game 240 how the tutor works 332
onc or two-player game 244 evaluating expressions 336
title sequences 249 20: GLOSSARY 339
hi-score routines 249
the Easy AMOS ChaIJenge 250 keywords and jargon 340
direct mode editor keys 404
15: HANDUNG DATA 251 editor control keys 405
using data 252 main menu options 408
sequential files 254 INDEX 413
random access files 257
designing a database 260
vii