ST ST7 - Local Symbols

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6 - STMicroelectronics Programming Tools
nition of the macro is:
IncByTwo MACRO TheByte
inc TheByte
inc TheByte
MEND
The macro is used by adding the symbol of the byte to be incremented:
IncByTwo CounterLo
The macro is expanded by the assembler to the following code:
44 IncByTwo CounterLo
44 000F 3C00 inc CounterLo
44 0011 3C00 inc CounterLo
Two or more arguments may be used. The following macro adds two variables and puts the
result in a third variable. The definition of the macro is:
Addition MACRO VarA, VarB, Result
ld A, VarA
add A, VarB
ld Result, A
MEND
The macro is used by typing the names of the symbols to be added and that of the result:
Addition NbOfApples, NbOfPears, NbOfFruit
The macro is expanded by the assembler into the following code:
57 Addition NbOfApples, NbOfPears,
NbOfFruit
57 0013 B602 ld A, NbOfApples
57 0015 BB03 add A, NbOfPears
57 0017 B704 ld NbOfFruit, A
6.1.7.2 Local symbols
You can insert statements that define symbols inside a macro, or labels in front of some oper-
ations. However, this can lead to problems. Let us consider the following macro that incre-