12.43 GBLA, GBLL, and GBLS

The GBLA, GBLL, and GBLS directives declare and initialize global variables.

Syntax

gblx variable
where:
gblx
is one of GBLA, GBLL, or GBLS.
variable
is the name of the variable. variable must be unique among symbols within a source file.

Usage

The GBLA directive declares a global arithmetic variable, and initializes its value to 0.
The GBLL directive declares a global logical variable, and initializes its value to {FALSE}.
The GBLS directive declares a global string variable and initializes its value to a null string, "".
Using one of these directives for a variable that is already defined re-initializes the variable.
The scope of the variable is limited to the source file that contains it.
Set the value of the variable with a SETA, SETL, or SETS directive.
Global variables can also be set with the --predefine assembler command-line option.

Examples

The following example declares a variable objectsize, sets the value of objectsize to 0xFF, and then uses it later in a SPACE directive:
            GBLA    objectsize    ; declare the variable name
objectsize  SETA    0xFF          ; set its value
            .
            .                     ; other code
            .
            SPACE   objectsize    ; quote the variable
The following example shows how to declare and set a variable when you invoke armasm. Use this when you want to set the value of a variable at assembly time. --pd is a synonym for --predefine.
armasm --predefine "objectsize SETA 0xFF" sourcefile -o objectfile
Related reference
12.50 LCLA, LCLL, and LCLS
12.63 SETA, SETL, and SETS
9.57 --predefine "directive"
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