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date Fri, 24 Apr 2009 22:36:09 +0000
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>3.5. Numbers and Expressions</A
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>&#13;Numbers can be expressed in binary, octal, decimal, or hexadecimal. Binary
numbers may be prefixed with a "%" symbol or suffixed with a "b" or "B".
Octal numbers may be prefixed with "@" or suffixed with "Q", "q", "O", or
"o". Hexadecimal numbers may be prefixed with "$", "0x" or "0X", or suffixed
with "H". No prefix or suffix is required for decimal numbers but they can
be prefixed with "&amp;" if desired. Any constant which begins with a letter
must be expressed with the correct prefix base identifier or be prefixed
with a 0. Thus hexadecimal FF would have to be written either 0FFH or $FF.
Numbers are not case sensitive.&#13;</P
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> A symbol may appear at any point where a number is acceptable. The
special symbol "*" can be used to represent the starting address of the
current source line within expressions. </P
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>The ASCII value of a character can be included by prefixing it with a
single quote ('). The ASCII values of two characters can be included by
prefixing the characters with a quote (").</P
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>LWASM supports the following basic binary operators: +, -, *, /, and %.
These represent addition, subtraction, multiplication, division, and modulus.
It also supports unary negation and unary 1's complement (- and ^ respectively).
For completeness, a unary positive (+) is supported though it is a no-op.</P
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>Operator precedence follows the usual rules. multiplication, division,
and modulus take precedence over addition and subtraction. Unary operators
take precedence over binary operators. To force a specific order of evaluation,
parentheses can be used in the usual manner.</P
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