C166/ST10 Cross-Assembler, Linker/Locator, Utilities ... - Tasking

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MACRO PREPROCESSOR
This expands to:
MOV R1, #DBFLAG
JMP DEBUG
MOV R1, R2
@SET can be changed to:
@SET( DEBUG, 0 )
to turn off the debug code.
2.6.4.2 WHILE FUNCTION
Chapter 2
The IF macro is useful for implementing one kind of conditional assembly
including or excluding lines of code in the source file. However, in many
cases this is not enough. Often you may wish to perform macro operations
until a certain condition is met. The built−in function WHILE provides this
facility.
Syntax:
@WHILE( expression )
statements
@ENDW
The WHILE function evaluates the expression. If it results to TRUE, the
statements are expanded; otherwise not. Once the statements have been
expanded, the logical arguments is retested and it’s still TRUE, the
statements are expanded again. This continues until the logical argument
proves FALSE.
Since the macro continues processing until the expression is FALSE, the
statements should modify the expression, or else WHILE may never
terminate.
A call to built−in function BREAK or EXIT always terminates a WHILE
macro. BREAK and EXIT are described below.
The following example shows the common use of the WHILE macro: