C51: COMMENTS IN ASSEMBLY BLOCKS

Information in this article applies to:

• C51 All Versions

SYMPTOM

When I try to place a comment in an assembly block or inside a C source file, such as:

#pragma asm
        mov R1, A  ; save function's return value
#pragma endasm

The compiler generates an error, thinking the apostrophe is a single quote.

CAUSE

Inline assembly code is parsed by the C compiler (which does not recognize the semicolon as the beginning of a comment).

RESOLUTION

Comments in ASM blocks should use C comment syntax. The example above compiles if changed to the following:

#pragma asm
        mov R1, A  // save function's return value
#pragma endasm

SEE ALSO

• GENERAL: SRC DIRECTIVE
• C51: PROBLEMS WITH #PRAGMA ASM
• C51: GETTING INLINE ASSEMBLY TO WORK
• C51: INLINE ASSEMBLY GENERATES TARGET OUT OF RANGE

Last Reviewed: Tuesday, May 24, 2005