Chapter
4.
Assembler
Directives
Example
3.
Nested IF's:
COND3:
IF
TYPE
EO
0
;ASSEMBLED
IF
'TYPE =
0'
;IS
TRUE
IF
MODE
EO
1
LEVEL ;ASSEMBLED
IF
'TYPE =
0'
;AND
'MODE =
l'
ARE
BOTH
;TRUE
ENDIF
ELSE
LEVEL
;ASSEMBLED
IF
'TYPE =
0'
2
;IS
FALSE
IF
MODE
EO
2
;ASSEMBLED
IF
'TYPE =
0'
;IS
FALSE
AND
'MODE =
2'
;IS
TRUE
LEVEL
ELSE
;ASSEMBLED
IF
'TYPE =
0'
;AND
'MODE =
2'
ARE
BOTH
;FALSE
ENDIF
ENDIF
ASSEMBLER
TERMINATION
END Directive
4-10
The
END
directive identifies the end
of
the source program and terminates each pass
of
the assembler.
Label Opcode Operand
optional:
END
expression
Only one
END
statement
ma)!
appear
in
a source program, and it must
be
the last source statement.
If
the optional expression
is
present, its value
is
used
as
the starting address for program execution. If
no
ex-
pression
is
given, the assembler assumes zero
as
the starting address.
When
a number
of
separate program modules are to
be
joined together, only one may specify a program
~tarting
address. The module with a starting address
is
the main module.
When
source files are combined using the
IN-
CLUDE control, there are
no
restrictions on which source file contains the END.
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