Epson S1C88 Series, Руководство пользователя

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APPENDIX B CREATING PROCEDURE OF ASSEMBLY SOURCE FILE (Sub tool chain)
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EPSON
S5U1C88000C MANUAL II
WORKBENCH/DEV TOOLS/OLD ASSEMBLER
For example :
sum macro c,d
ld a,[c]
add a,d
sld [c],a
endm
sum total,#20
The above will be interpreted as follows :
l#20 a,[total]
a#20#20 a,#20
l#20
[total],a
If you redefine your macro definition as shown below, your input will be correctly replaced :
sum macro c,&d
ld a,[c]
add a,&d
ld [c],a
endm
The blank characters before and after parameters and arguments will be discarded. The blank charac-
ters inside parameters and arguments, however, are valid. Please take caution in this respect. A macro
call from inside the body of the macro for a macro definition can also be done. In this case, a macro
call should be initiated at the time the macro call generates.
For example :
maca macro x,y
add x,y
endm
macb macro x,y
maca x,y
endm
macb a,#2
→
add a,#2
maca macro x,y
sub x,y
endm
macb a,#2
→
sub a,#2
A macro call from the body of the macro can be executed according to the depth of your choice.
However, if the call enters a loop, the macro call will be suspended. Take a simple example for
instance :
add macro x,y
ld a,x
add a,y
ld x,a
endm
When the macro defined as above is called, it is expanded as follows :
ld a,b
add b,#2
→
add a,#2
ld b,a
"add a,y" in the third line will call itself. The macro call, therefore, will not occur. It will turn out to be
a simple "add" instruction. If we take a look at a little more complicated example :
maca macro x,y
macb x,y
macc x,y
endm