CHAPTER 4: ASSEMBLER

Expansion rules

When a defined macro name appears in the source, the assembler inserts a statement string defined in that location.

If there are actual parameters described in that process, the dummy parameters will be replaced with the actual parameters in the same order as the latter are arranged.

The internal branch labels are replaced, respectively, with __L0001 ... from top of the source in the same order as they appear.

Sample expansion:

When the macro WAIT shown above is defined:

Macro invocation

:

WAIT 15

:

After expansion

:

;WAIT 15 ld %a,15 and %f,0b1101

__L0001:

nop

jr __L0001

("__L0001" denotes the case where an internal branch label is expanded for the first time in the source.)

Precautions

•The assembler only permits backward reference of a macro invocation. Therefore the macro definition must precede the use of it.

•Once a defined macro name is defined, it cannot be canceled. If the same macro name is defined duplicatedly, a warning message will appear. Until it is redefined, it is expanded with the original content, and once it is redefined, it is expanded with the new content. Definition should be done with distinct names, although the program operation will not be affected.

•No other characters than delimiters (space, tab, line feed, and commas) can be added before and after a dummy parameter in a statement.

•The same character string as that of the define instruction cannot be used as a macro name.

•When the number of dummy parameters differs from that of actual parameters, an error will result.

•The maximum number of parameters and internal branch labels are limited according to the free memory space.

•"__Lnnnn" used for the internal branch labels should not be employed as other label or symbol.

S5U1C63000A MANUAL

EPSON

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(S1C63 FAMILY ASSEMBLER PACKAGE)