Zilog Z8F0130 - Manual (Page 326)

Using the Macro Assembler UM013037-1212
302
Zilog Developer Studio II – Z8 Encore!
User Manual
•
ALIGN Clause – see page 302
•
MAYINIT Clause – see page 302
•
ORG Clause – see page 303
•
SPACE Clause – see page 303
Synonym
.define
Syntax
<segment_definition> =>
DEFINE <ident>[<space_clause>][align_clause>][<org_clause>][<mayinit_clause>]
Examples
DEFINE near_code ; Uses the defaults of the current

; space, byte alignment and relocatable.

DEFINE irq_table,ORG=%FFF8 ; Uses current space, byte alignment,

; and absolute starting address at
; memory location %FFF8.
ALIGN Clause
Allows you to select the alignment boundary for a segment. The linker places modules in
this segment on the defined boundary. The boundary, expressed in bytes, must be a power
of two (1, 2, 4, 8, and so on).
Syntax
<align_clause> => , ALIGN = <int_const>
Example
DEFINE fdata,SPACE = EData,ALIGN = 2

; Aligns on 2-byte boundary, relocatable.
MAYINIT Clause
A MAYINIT clause explicitly allows data in the segment to be initialized by, for example,
DB directives. Only segments in ROM or EROM can be directly initialized by assembler,
and the MAYINIT clause is not necessary for segments in these spaces. The initialization
of segments in RDATA or EDATA requires coordination of the assembler, linker, and
start-up code. If you must initialize data in a segment in RDATA or EDATA, use the
MAYINIT clause to enable the initialization directives in that segment. See the note in the
Predefined Segments section on page 279 on how to use start-up code to complete the ini-
tialization.