Apple Business BASIC

173 Pages·2011·10.15 MB·English

Apple Business BASIC
Reference Manual - Volume 1
Notice
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Preface
vi
1 Introduction to Apple Business BASIC 1
1 Introduction
10 Controlling Text On the Screen
17 System and Utility Statements
18 Loading and Saving Programs
20 Starting and Stopping Programs
23 Handling Large Programs
25 Debugging Programs
26 Special Keys
28 Automatic Execution
2 Tools of Your Trade 38
38 Introduction
39 Variable Types
43 Reserved Words and Variables
44 Arrays
47 Statements
48 Expressions
54 Functions
56 Business BASIC Functions
57 String Functions
65 Numeric Functions
70 Defining Your Own Functions
3 Apple Business BASIC I /0 74
74 Introduction
75 Displaying Text On The Screen
78 Entering Data
82 Storing Data Within Your Program
86 Formatting Information
4
Controlling Program Execution 102
102 Assignment Statements
104 Remark Statements
105 Branching
110 Looping
115 Subroutines
118 Computed Branching
121 Handling Errors
124 Error-recovery Strategies
5
File 1/0 128
128 Introduction
128 Filenames
130 Creating Files
132 Manipulating Files
136 File Types
136 Opening and Closing Files
139 Accessing Files
142 Data Files
145 Sequential Access
150 Random Access
153 File Functions and Statements
156 File 1/0 Example
6
External Routines 101
101 INVOKE
162 PERFORM
164 EXFN.
165 EXFN%.
7
Apple Ill Business BASIC References 166
Appendices
A
ASCII Character Codes 220
B
Errors 226
C
Variable Maps 236
D Alphabetical List of Reserved Words 238
E
Space Savers 242
F
Memory Usage 246
G
Speeding Program Execution 250
H
Summary of Apple Business BASIC 252
I
Using the Graphics lnvokable Module 212
274 Overview of the Graphics Display
277 Overview of the Graphics Routines
281 Details of the Graphics Routines
288 Viewports and Colors
298 Moves
301 Screen Information Functions
303 Displaying Text and Other Images
308 Preserving Your Graphics
309 After Graphics
312 Graphics in Display Mode 1
314 Creating and Storing a Bit Array
·3 21 Direct Control of the Screen
324 Summary
Index 330
This book is intended to provide you with the information you need to
learn and use the Apple Business BASIC programming language. If
you are new to the world of computers, or are not familiar with one or
more other dialects of BASIC, you should first study a good textbook
on elementary programming. You should also read the Apple Ill
Owner's Guide that is packed with your computer before reading this
manual.
The material in this manual is presented primarily for programmers
with some experience, but enough examples, simplified procedures,
and descriptions are included to enable you to use it effectively even
if you are a beginner.
To make the use of this manual easier for you, we have divided it into
two volumes. After you have become familiar with the material in the
first part, you can quickly refer to details of Business BASIC as found
in the reference portion of the manual, which is contained in the
second volume. Paging is continuous through the manual, and the
· index is placed in the reference volume.
When important terms are first introduced in this manual, they are
italicized. Three special symbols are used in this book to point out
places where you should pay attention:
@
The pointing finger indicates an especially useful or
noteworthy piece of information.
@
The eye means "watch out!" It indicates a description
of a special feature to which you should be alert.
~
The stop sign means that in the situation described,
you should be especially cautious, because if you do
something incorrect, BASIC may not be able to
recover. You may have to restart BASIC, and this
means that you will probably lose your program.
2 Introduction
3 Starting Up
5 Immediate and Deferred Execution
6 Editing Your Program
9 Interrupting a Running Program
10 Controlling Text On the Screen
10 LIST
11 The Reserved Variables INDENT and OUTREC
12 DEL
13 WINDOW
14 TEXT
15 The Reserved Variables VPOS and HPOS
16 HOME
16 INVERSE and NORMAL
17 System and Utility Statements
17 Memory Management
17 NEW
17 CLEAR
18 The Reserved Variable FRE