Panasonic PanaXSeries MN1030 Series, Руководство пользователя

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Chapter 8 Writing Source Statements
Address Constants 135
8.5 Address Constants
Address constants return particular bits from expressions that can be evaluated as addresses.
They are written as follows.
address_specifier (expression)
An address constant is written as an expression enclosed in parentheses following an address specifier.
An expression consists of names, self-reference address symbols, and constants linked by operators,
with the result representing a single value (refer to section 8.7, "Expressions", for details).
The address specifiers are shown below.
A or a Return the lower 32 bits of the expression value (bits
0 to 31)).
Example:
Assume that the following address is assigned to the label with the name MESSAGE.
address= 00000000001110010101011011101001(binary)
a(MESSAGE) represents 00000000001110010101011011101001
The values expressed by MESSAGE and a(MESSAGE) are the same. In a context calling for the
address value associated with a symbol, it is more common to use the symbol itself alone instead of
adding the address specifier.