Holtek HT-IDE, User Manual

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The LOCAL directive defines symbols available only in the defined macro.
The dummy-name is a temporary name that is replaced by an unique name
when the macro is expanded. The HASM creates a new actual name for
dummy-name each time the macro is expanded. The actual name has the
form ??digit, where digit is a hexadecimal number within the range from
0000 to FFFF. A label should be be added to the LOCAL directive when
labels are used within the MACRO/ENDM block. Otherwise, the HASM
will issue an error if this MACRO is referred to more than once in the source
file.
In the following example, tmp1 and tmp2 are both dummy parameters, and
are replaced by actual parameters when calling this macro. label1 and
label2 are both declared LOCAL, and are replaced by ??0000 and ??0001
respectively at the first reference, if no other macro is referred. If no LOCAL
declaration takes place, label1 and label2 will be referred to labels, similar
to the declaration in the source program. At the second reference of this
macro, a multiple define error message is displayed.
Delay MACRO tmp1, tmp2
LOCAL label1, label2
mov a, 70h
mov tmp1, a
label1:
mov tmp2, a
label2:
clr wdt1
clr wdt2
sdz tmp2
jmp label2
sdz tmp1
jmp label1
ENDM
The following source program refers to the macro Delay ...
; T.ASM --
; Sample program for MACRO.
.ListMacro
Delay MACRO tmp1, tmp2
LOCAL label1, label2
mov a, 70h
mov tmp1, a
label1:
mov tmp2, a
label2
clr wdt1
clr wdt2
sdz tmp2
jmp label2
sdz tmp1
HT-IDE User’s Guide
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