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Q24965: Jump to Absolute Address

Article: Q24965
Product(s): Microsoft Macro Assembler
Version(s): 1.25,1.27,3.0x,4.0,5.0,5.1,5.1a,6.0,6.0a,6.0b
Operating System(s): 
Keyword(s): 
Last Modified: 06-MAY-2001

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The information in this article applies to:

- Microsoft Macro Assembler (MASM), versions 1.25, 1.27, 3.0x, 4.0, 5.0, 5.1, 5.1a, 6.0, 6.0a, 6.0b 
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SUMMARY
=======

There are two methods of coding a jump to an absolute address. These methods are
as follows:

1. Use AT to create a segment template beginning at an absolute address. Then,
  using ORG, a label can be assigned at a specific offset.

-or-

2. Initialize a double word variable to the specific address.

MORE INFORMATION
================

The following code demonstrates both methods:

  ; Assembly options needed: none

  ASEG SEGMENT BYTE AT 0000H

             ORG 100
  far_label  LABEL FAR

  ASEG       ENDS

  DATA   SEGMENT WORD 'DATA'

  FAR_VAR DW   100,0

  DATA         ENDS

  CODE   SEGMENT BYTE 'CODE'
         ASSUME CS:CODE, DS:DATA

  start: mov ax, data
         mov ds, ax

         JMP far_label          ;This is the first type of jump.

         JMP DWORD PTR far_var  ;This is the second type of jump.
  CODE   ENDS

  END start

Additional query words: 1.25 1.27 3.0x 4.00 5.00 5.10 5.10a 6.00 6.00a 6.00b

======================================================================
Keywords          :  
Technology        : kbMASMsearch kbAudDeveloper kbMASM510 kbMASM600 kbMASM125 kbMASM127 kbMASM30xSearch kbMASM400 kbMASM500 kbMASM600a kbMASM510a kbMASM600b
Version           : :1.25,1.27,3.0x,4.0,5.0,5.1,5.1a,6.0,6.0a,6.0b

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