Zilog EZ80F916 - Manual (Page 218)

UM014423-0607
ZiLOG Developer Studio II
eZ80Acclaim! ® User Manual
198
Example
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CPU
Defines to the assembler which member of the eZ80Acclaim! family is targeted. From this
directive, the assembler can determine which instructions are legal as well as the locations
of the interrupt vectors within the CODE space.
The CPU directive can use the following predefined symbols:
•
EZ80F93
•
EZ80F92
•
EZ80F91
•
EZ80L92
•
EZ80190
When eZ80F91, for example, is selected, the following preprocessor symbols are automat-
ically defined (note the leading underscore):
_EZ80F91=1
_EZ80F92=0
_EZ80F93=0
_EZ80L92=0
_EZ80190=0
The symbols are defined in a similar fashion when any other CPU is selected.
These preprocessor symbols can be used for conditional assembly. For example:
.if _EZ80F91
...
.endif
Using the predefined symbols with the
IFDEF
conditional assembly directive in your code
does not produce useful results, precisely because the symbols are already defined as
either 0 or 1. For example, the following always evaluates to true:
IFDEF _EZ80190
Instead, use a preprocessor symbol that is not predefined, as in the following code:
EZ80190 EQU 1
IFDEF EZ80190
NOTE: The
CPU
directive is used to determine the physical location of the interrupt
vectors.