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Exceptions

While the C preprocessor in the assembler works almost like the preprocessor in the C compiler, there are several exceptions that are important to note.

  • The predefined macros are different for the assembler and compiler.
  • The assembler does not accept C escape sequences like "\n", "\r", or "\x0D". If you use these characters in a #define you must replace them with explicit HEX values.
  • Unlike the C compiler, the assembler does not concatenate multiple strings into a single string. Therefore, you must separate strings with a comma (',') for the assembler to concatenate them.
  • The #message directive is not available.
  • The #warning directive is not available.
  • The #pragma directive may be used to specify Assembler Directives.
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