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MOTOROLA
DSP ASSEMBLER REFERENCE MANUAL
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4-9
<llc>
Which load counter, H, L, or default (if neither H or L is specified), that is as-
sociated with the <lms> will be used as the load location counter.
<lmp>
Indicates the load physical mapping to DSP memory: I - internal, E - exter-
nal, R - ROM, A - port A, B - port B. If not present, no explicit mapping is
done.
<lce>
Non-negative absolute integer expression representing the counter number
to be used as the load location counter. Must be enclosed in parentheses.
Should not exceed the value 65535.
<exp2>
Initial value to assign to the load counter used as the <llc>. If <exp2> is a
relative expression the Assembler uses the relative location counter. If
<exp2> is an absolute expression the Assembler uses the absolute loca-
tion counter. If <exp2> is not specified, then the last value and mode that
the counter had will be used.
The
ORG
directive is useful in multi-programmer projects because it provides a means for
the individual programmer to specify in which memory space and which segment of that
memory space the code being written will be located without specifying an absolute ad-
dress. Absolute address assignment can be deferred until the various components of the
program are brought together. The utility of the
ORG
directive is not limited to multi-pro-
grammer projects. Even in single programmer projects, the
ORG
directive supports ma-
nipulation of overlays and the intermixing of label definition and code generation in
multiple memory spaces without having to reinitialize a location counter every time the
load memory space is changed.
4.5.2
Overlays
If the last half of the operand field in an
ORG
directive dealing with the load memory space
and counter is not specified, then the Assembler will assume that the load memory space
and load location counter are the same as the runtime memory space and runtime loca-
tion counter. In this case, object code is being assembled to be loaded into the address
and memory space where it will be when the program is run, and is not an overlay.
If the load memory space and counter are given in the operand field, then the Assembler
always generates code for an overlay. Whether the overlay is absolute or relocatable de-
pends upon the current operating mode of the Assembler and whether the load counter
value is an absolute or relative expression. If the Assembler is running in absolute mode,
or if the load counter expression is absolute, then the overlay is absolute. If the Assembler
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