Motorola HC12 User Manual

User’s Manual

MCUez HC12 Assembler

190

Assembler Directives

MOTOROLA

Syntax:

MEXIT

Description:

MEXIT

 is usually used together with conditional assembly

within a macro. In that case, macro expansion might terminate
prior to terminating the macro definition. The

MEXIT

directive

causes macro expansion to skip any remaining source lines
ahead of the

ENDM

 directive.

Example:

This portion of code:

sav2: MACRO

; Start macro definition

        ldx  savet

        ldaa \1

        staa 0,x

; save first argument

        ldaa \2

        staa 2,x

; save second argument

        ifc  '\3', ''

; is there a 3rd argument?

          mexit

; no, exit from macro.

        endif

        ldaa \3

; save third argument

        staa 4, x

      endm

; End of macro definition

entry:

      sav2 char1, char2

Generates this listing file:

27  11m

000000 FE xxxx

+

ldx  savet

28  12m

000003 B6 xxxx

+

ldaa char1

29  13m

000006 6A00

+

staa 0,x;save first

 ; argument

30  14m

000008 B6 xxxx

+

ldaa char2

31  15m

00000B 6A02

+

staa 2,x ;save second

 ; argument

32  16m

+

33  17m

0000 0001

+ ifc  '',''

 ;is there a

 ; 3rd arg.

35

18m

+

mexit

 ;no,exit macro.

36

19m

+

endif

37

20m

+

38

21m

+

ldaa

 ;save third

 ; argument

39

22m

+

staa 4, x