Zilog EZ80F916 - Manual (Page 270)

UM014423-0607 Using the Linker/Locator
ZiLOG Developer Studio II
eZ80Acclaim! ® User Manual
250
Examples
To make a copy of a code segment in ROM, use the following procedure:
1. In the assembly code, define a code segment (for example,
codeseg
) to be a segment
located in RAM. This is the run-time location of
codeseg
.
2. Use the following linker command:
COPY codeseg ROM
The linker places the actual contents associated with
codeseg
in ROM (the load time
location) and associates RAM (the run-time location) addresses with labels in
codeseg
.
NOTE: You need to copy the
codeseg
contents from ROM to RAM at run time as part of the
startup routine. You can use the
COPY BASE OF
and
COPY TOP OF
linker expressions to
get the base address and top address of the contents in ROM. You can use the BASE OF
and TOP OF linker expressions to get the base address and top address of
codeseg
.
To copy multiple segments to RAM, use the following procedure:
1. In the assembly code, define the segments (for example,
strseg
,
text
, and
codeseg
) to be segments located in RAM. This is the run-time location of the
segments.
2. Use the following linker commands:
CHANGE strseg=codeseg
CHANGE text=codeseg
COPY codeseg RAM
The linker renames
strseg
and
text
as
codeseg
and performs linking as described
in the previous example. You need to write only one loop to perform the copy from
ROM to RAM at run time, instead of three (one loop each for
strseg
,
text
, and
codeseg
).
To allocate a string segment in ROM but not generate the initialization, use the following
procedure:
1. In the assembly code, define the string segment (for example,
strsect
) to be a
segment located in ROM.
2. Use the following linker command:
COPY strsect NULL
The linker associates all the labels in
strsect
with an address in ROM and does not
generate any loadable data for
strsect
. This is useful when ROM is already
programmed separately, and the address information is needed for linking and
debugging.