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.EXTERN

Declares to the optimizing linker that a symbol in another module is to be referenced in this module.

[Syntax]

Symbol field	Mnemonic field	Operand field	Comment field
[label:]	.EXTERN	symbol-name	[; comment]

[Function]

-	The .EXTERN directive declares to the optimizing linker that a symbol in another module is to be referenced in this module.

[Description]

-	The symbol specified in the operand field can be referenced in the current module.

-	The following cannot be written as an operand.

(a)	Symbol defined with the .SET directive

(b)	Section name

(c)	Macro name

-	No error is output even if a symbol declared with the .EXTERN directive is not referenced in the given module.

-	The .EXTERN directive may be described anywhere in a source program.

[Example]

Referring program

         .EXTERN  PSYM01

         .EXTERN  PSYM02

         MOV      A, ES:!PSYM01

         BR       !PSYM02

Defining program

         .PUBLIC  PSYM01

         .PUBLIC  PSYM02

PSYM01:  .DB      0x10

PSYM02:  MOV      A, #0x4D