Intel 8080 - B4_Page_12

Chapter 5. Macros
MAIN PROGRAM
SUBSTITUTION
JNZ NEXT
JNZ
NEXT
LOAD FLD,FLD+1,FLD+2
??OOOl : LHLD FLD
MOY M,A ;INYERT BYTES
MOY A,M
DCX H
LHLD
FLD+1
MOY
M,B
MOY B,M
DCX
H
LHLD
FLD+2
MOY
M,G
MOY C,M
LOAD
3EOH ,BYTE ,CHECK
MOY
M,A
;INYERT BYTES
ADD
B
;CHECK DIGIT
DCX H
CMP C
MOY
M,B
CNZ
DGTBAD
DCX H
MOY
M,C
??0002: LHLD
3EOH
MOY A,M
LHLD
BYTE
MOY B,M
LHLD
CHECK
MOY C,M
ADD B
;CHECK DIGIT
CMP C
CNZ
DGTBAD
Nested Macro Calls
5·14
Macro calls (including any combination of nested IRP, IRPC, and REPT constructs) can be nested within macro
definitions
up to eight levels. The macro being called need not be defined when the enclosing macro is defined;
however, it must
be defined before the enclosing macro is called.
A macro definition can also contain nested calls to itself (recursive macro calls) up to eight levels, as long as the
recursive macro expansions can
be terminated eventually. This operation can be controlled using the conditional
assembly directives described
in Chapter 4 (IF, ELSE, ENDIF).
Example:
Have a macro call itself five times after it is called from elsewhere in the program.
PARAM1
RECALL
PARAM1
SET
MACRO
5
IF PARAM1 NE 0
SET PARAM 1-1
RECALL
ENDIF
ENDM
;RECURSIYE CALL