Variables
You can declare numeric, logical, or string variables using assembler directives.
The value of a variable can be changed as assembly proceeds. Variables are local to the assembler. This means that in the generated code or data, every instance of the variable has a fixed value.
The type of a variable cannot be changed. Variables are one of the following types:
Numeric.
Logical.
String.
The range of possible values of a numeric variable is the same as the range of possible values of a numeric constant or numeric expression.
The possible values of a logical variable are {TRUE}
or {FALSE}
.
The range of possible values of a string variable is the same as the range of values of a string expression.
Use the GBLA
, GBLL
, GBLS
, LCLA
, LCLL
,
and LCLS
directives to declare symbols representing variables,
and assign values to them using the SETA
, SETL
,
and SETS
directives.
Example
a SETA 100 L1 MOV R1, #(a*5) ; In the object file, this is MOV R1, #500 a SETA 200 ; Value of 'a' is 200 only after this point. ; The previous instruction is always MOV R1, #500 … BNE L1 ; When the processor branches to L1, it executes ; MOV R1, #500