Zilog Z8F0130 - Manual (Page 308)

Using the Macro Assembler UM013037-1212
284
Zilog Developer Studio II – Z8 Encore!
User Manual
•
Instruction – see page 285
•
Directive – see page 285
•
Case Sensitivity – see page 285
Source Line
A source line is composed of an optional label followed by an instruction or a directive. It
is possible for a source line to contain only a label field.
Comment Line
A semicolon (;) terminates the scanning action of the assembler. Any text following the
semicolon is treated as a comment. A semicolon that appears as the first character causes
the entire line to be treated as comment.
Label Field
A label must meet at least one of the following conditions:
•
It must be followed by a colon.
•
It must start at the beginning of the line with no preceding white space (start in column
1).
•
It can be defined by an EQU directive using the following syntax:
<label> EQU <expression>
See the EQU section on page 304 for more information about this type of label defini-
tion.
•
Any instruction followed by a colon is treated as a label.
•
Any instruction not followed by a colon is treated as an instruction, even if it starts in
the first column.
The first character of a label can be a letter, an underscore _ , a dollar sign ($), a question
mark (?), a period (.), or pound sign (#). Following characters can include letters, digits,
underscores, dollar signs ($), question marks (?), periods (.), or pound signs (#). The label
can be followed by a colon (:) that completes the label definition. A label can only be
defined once. The maximum label length is 129 characters.
Labels that can be interpreted as hexadecimal numbers are not allowed.
For example:
ADH:

ABEFH:
cannot be used as labels.