Holtek HT-IDE, User Manual

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Operation
The operation defines the statement action of which two types exist,
directives and instructions. Directives give directions to the assembler,
specifying the manner in which the assembler is to generate the object code
at assembly time. Instructions, on the other hand, give directions to the
processor. They are translated to object code at assembly time, the object
code in turn controlling the behavior of the processor at run time.
Operand
Operands define the data used by directives and instructions. They can be
made up of symbols, constants, expressions and registers.
Comment
Comments are the descriptions of codes. They are used for documentation
only and are ignored by the assembler. Any text following a semicolon is
considered a comment.
Assembly Directives
Directives give direction to the assembler, specifying the manner in which
the assembler generates object code at assembly time. Directives can be
further classified according to their behavior as described below.
Conditional-Assembly directives
The conditional block has the following form:
IF
statements
[ELSE
statements]
ENDIF
→
Syntax
IF
expression
IFE
expression
•
Description
The directives IF and IFE test the expression following them.
The IF directive grants assembly if the value of the expression is true, i.e.
non-zero.
The IFE directive grants assembly if the value of the expression is false,
i.e. zero.
Chapter 10 Assembly Language and Cross Assembler
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