Chapter 10 Writing Assembler Control StatementsIdentifier Definement 18710.3.1 #defineSyntax#define [replacement_string] [; comment]Functional descriptionThis directive causes the assembler to replace the identifier with the replacement_string on all furtherlines.The #define directive differs from the #equ directive in that a string can be specified. Furthermore,when used in conjunction with the #undef directive, redefinition is possible.Coding rulesAny string can be coded for the replacement_string. The string can include spaces and tabs. If thereplacement_string is omitted, the identifier will be defined as a null character.Everything after a semicolon (;) is considered a comment. Therefore semicolons cannot be included inthe replacement_string.The same identifier cannot just be redefined with another #define directive. When used in conjunctionwith the #undef directive, redefinition is possible. Refer to section 10.4, "#undef", for details.If the replacement_string is omitted, the identifier will be defined as a null character.Usage exampleSource file contents are shown below. The first line replaces data with the character 5. The next line isan example of changing a mnemonic, so mov data,D0 can be coded as load.#define data 5#define load mov data, D0_CODE section CODE, PUBLIC,2mainmov data, D0loadend
