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Predefined Macros

The Cx51 Compiler provides the following predefined constants you may use in preprocessor directives and C code to create portable programs.

Constant Description
__C51__ Version number of the compiler (for example, 701 for version 7.01).
__CX51__ Version number of the compiler (for example, 701 for version 7.01).
__DATE__ Date when the compilation was started in ANSI format (month dd yyyy).
__DATE2__ Date when the compilation was started in short form (mm/dd/yy).
__FILE__ Name of the file being compiled.
__LINE__ Current line number in the file being compiled.
__MODEL__ Memory model selected:
__TIME__ Time when the compilation was started. (Format: hh:mm:ss)
__STDC__ Defined to 1 to indicate full conformance with the ANSI C Standard.

Note

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