ZBasic Language Reference
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ZBasic Microcontrollers
used for small-valued data but they are not quite as efficient with respect to code size as using Byte
types. See Section 3.24 for more information on these special types. Also, two special string types are
available – Bounded Strings and Fixed Length strings. These are supported largely for compatibility with
BasicX but may be useful in special situations. See Section 2.11.1 and Section 2.11.2 for more
information on Bounded Strings and Fixed Length strings, respectively.
ZBasic is a strongly typed language that doesn’t allow you to freely intermix different data types. This
helps prevent programming errors or unexpected program behavior that results from unanticipated type
conversions. However, a series of well-defined type conversion functions is provided that allow you to
make explicit type conversions when necessary. See Section 2.13 for more information. Lastly, Section
3.28 contains technical details of the implementation of the various data types. This information is
generally not necessary for most programming purposes but it is sometimes useful to know.
2.3 Modules
A ZBasic program may comprise one or more modules each contained within a separate file. When a
module is compiled, a module name is derived from the name of the file. The module name is mostly for
internal use by the compiler but you’ll find references to the module name in the generated map file.
Also, in some special situations you may need to use the module name as part of an identifier in order to
refer to a variable or constant in your code. This is usually not necessary but it is good to remember that
it is available. See Section 3.1 for more information on resolving identifier references using the module
name.
The module name is derived by first removing the path prefix, if any, and the extension (typically .bas).
The remaining characters of the filename are examined and any character that is not a letter, a digit or an
underscore is replaced with an underscore. For the most part, this process converts the filename into a
legal ZBasic identifier.
As an example, consider the filename “C:\temp\my test code-1.bas“. When you compile this
module the derived module name is my_test_code_1. If you compile a file whose corresponding
module name does not begin with a letter, the compilation will proceed as normal. However, you will not
be able to refer to that module by its module name since it will not be a legal ZBasic identifier.
A module is divided conceptually into two sections: an options section which, if present, must be first, and
a definitions section. The definitions section may also be omitted but with no definitions, the module
serves no useful purpose.
2.3.1 The Options Section
The options section contains directives that tell the compiler how to process the definitions section that
follows. In the absence of any option directives, the compiler uses certain default settings as described
below. This means that it is perfectly reasonable, and quite common, not to have any option directives in
a module. The options section may also contain comments. This is useful for documenting what you’re
trying to accomplish with each option directive.
Note that some of the settings affected by the option directives described in this section may also be
affected by compiler command line options. Option directives have precedence over command line
options. See Section 10.1 for more information on command line options.
Unless otherwise indicated, option directives have global scope and may only appear in the first module
compiled.
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