4.6 Identifiers
Assembly identifiers are user-defined symbols representing memory
locations or numbers. A symbol can contain any number of characters drawn from alphabetics,
numerics, as well as special characters: dollar, $
; question mark,
?
; and underscore, _
.
The first character of an identifier cannot be numeric nor the
$
character. The case of alphabetics is significant, e.g.,
is not the same symbol as
Fred
fred
. Some examples of identifiers are shown here:
An_identifier
an_identifier
an_identifier1
?$_12345
An identifier cannot have the same symbol (any case) as any of the
assembly code mnemonics (e.g. movlw
or return
) assembler
directives (e.g. SET
or LIST
), directive argument tokens
(e.g. hex
or push
), or operators (e.g.
mod
or nul
).