Commodore Plus 4 - CHAPTER 1 Unpacking and Setting Up

The BASIC Language
This chapter contains information on each of the BASIC commands, functions,
and system reserved variables. Other important details about BASIC are
included in the beginning sections.
The Elements of BASIC
The BASIC built into the Plus/4 is called Version 3.5. This version of BASIC is
considerably more sophisticated than the Version 2.0 built into the Commodore 64.
Version 3.5 contains about twice the number of BASIC commands and is easier
to use.
This chapter explains each of the 75+ BASIC commands in Version 3.5. In
addition, all BASIC functions are explained. The functions and the commands
are explained together in alphabetical order. The possible parameters of all
commands and functions are discussed. For some commands, such as the draw
ing commands, you must type a place-holder comma when you use the default
value for a parameter. Be sure to note the requirements for each command.
BASIC lets you perform a large variety of tasks; despite this versatility, BASIC
has very strict syntax rules. You must enter commands according to their formats
and use only legal parameters. When you make a mistake, BASIC usually aborts
the program and displays an error message. Appendix A explains the error
messages that BASIC prints to help you diagnose your mistakes. The description
of the HELP command explains how to use the HELP key to find errors in
programming lines.
Note the following definitions if you are unsure of some terms:
Keyword A keyword is a word that is reserved as part of BASIC. Keywords
include commands, parts of commands (such as TO, which is part of the FOR
command), operators, function names, and certain reserved variables such as
TI$, a hardware timing value, and ER, an error-diagnosing variable. Keywords
cannot be used as variable names or be embedded in variable names.
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