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Predefined Macros

The CARM Compiler provides the following predefined constants you may use in preprocessor directives and C code to create portable programs.

Constant Description
__CA__ Version number of the compiler (for example, 101 for version 1.01).
__DATE__ Date when the compilation was started in ANSI format (month dd yyyy).
__FILE__ Name of the file being compiled.
__FLOAT64__ Defined to 1 to indicate that the FLOAT64 directive is active.
__KEIL__ Defined to 1 to indicate the Keil CARM Compiler is used.
__LINE__ Current line number in the file being compiled.
__THUMB__ CPU mode selected:
__TIME__ Time when the compilation was started.
__STDC__ Defined to 1 to indicate full conformance with the ANSI C Standard.


  • There are two (2) leading and trailing underscore characters ('_') used for the predefined constants.
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