Assembler

END expression: Expression defines the start vector for the current assembly program. This directive generates the following assembly code;

AORG 0xFFFF

DATA expression

which defines the start vector of the program, i.e., the program address where execution begins when the chip is installed.

label EQU expression: Associates the value of expression with label.

EXTERNAL symbol[,symbol]: This directive is used to indicate to the assembler that one or more symbols are external references, i.e., symbols that will be resolved by the linker.

GLOBAL symbol[,symbol]: This directive is used to indicate to the assembler that one or more symbols are global references. These symbols MUST be defined in the current file, and will be used by the linker to resolve external references (present in other files). GLOBAL should only be used for PROGRAM labels. RAM variables are handled with the GLOBAL_VAR directive.

GLOBAL_VAR symbol[,symbol]: This directive allows a RAM variable to be referenced from another file. GLOBAL_VAR should be used prior to defining a RAM variable (with the RESW directive, for example). The file that references the variable should declare it as EXTERNAL (of REF). Note that this technique can also be used to make constants defined with the EQU statement available to other files.

INCLUDE filename: This directive is used to insert another file in the current assembly file. The name of the file must be enclosed in double quotes. If the file name itself is enclosed in angled brackets (<>), then the assembler will first look for the include file in the include directory list that is passed as an argument during the DLL call.

LIST: The lines following this directive are included in the listing file (extension .lst) created by the assembler.

REF symbol[,symbol]: Equivalent to EXTERNAL directive

label RESB expression: This directive is used to reserve the number of bytes indicated by expression, starting at the current RAM address. Label is given the value of the current RAM address.

Code Development Tools

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Texas Instruments MSP50C6xx manual Assembler