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5.1.12 Identifiers

An identifier is a name used for symbols, labels, macros etc.

Identifiers are described according to the following basic rules.

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Identifiers consist of alphanumeric characters and symbols that are used as characters (@,_, .)
However, the first character cannot be a number (0 to 9).

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Reserved words cannot be used as identifiers.
With regard to reserved words, see "5.5 Reserved Words".

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The assembler distinguishes between uppercase and lowercase.