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Kevin_Zheng



Joined: 04 Jul 2003
Posts: 125
Location: China
Kevin_Zheng
Hi, All:
I'm writting a pure assembly win32 application through MS COFF format, there are three assembly files on it, I've defined a struct variable on first file, and I want to use extrn syntax to access this struct variable. But unfortunately, I've found that the extrn and as instrcution don't support struct macro. Are you good advise for it?

Hi, Tomas:
I think that you maybe define the struct as a internal keyword for example align keyword, it maybe more useful than macro define.

Thanks.

Kevin Zheng

Code:
A.file:
struct SPIOpStruct
  Preop0         db     ?; preop 0 (Write enable)            
  Preop1         db     ?; preop 1 (Write status register)   
ends

b.file:
EXTRN   '_SpiReg'               AS      SpiReg:SpiOpStruct

mov     [SpiReg.Preop0], ebx
    
Post 06 Sep 2006, 02:02
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IceStudent



Joined: 19 Dec 2003
Posts: 60
Location: Ukraine
IceStudent
You must use a struct declaration as in the HLL and 'virtual' wrapper:

Code:
; struct.inc
struct SPIOpStruct 
  Preop0         db     ?; preop 0 (Write enable)             
  Preop1         db     ?; preop 1 (Write status register)    
ends

; A.file
include 'struct.inc'

; data definition
SpiReg SPIOpStruct
public SpiReg as '_SpiReg'

B.file
include 'struct.inc' ; struct declaration
EXTRN   '_SpiReg'               AS      SpiReg:word ; SpiReg declaration

; place new ..SpiReg at external SpiReg address
virtual at SpiReg
        ..SpiReg SPIOpStruct
end virtual

; and now use it
mov             [..SpiReg.Preop0],al    
Post 06 Sep 2006, 06:07
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Kevin_Zheng



Joined: 04 Jul 2003
Posts: 125
Location: China
Kevin_Zheng
Hi, IceStudent:
Thank you very much! It's a very good soultion for it. And other, I have another method to do it.
Code:
; struct.inc 
struct SPIOpStruct  
  Preop0         db     ?; preop 0 (Write enable)              
  Preop1         db     ?; preop 1 (Write status register)     
ends 

; A.file 
include 'struct.inc' 

; data definition 
SpiReg SPIOpStruct 
public SpiReg as '_SpiReg' 

B.file 
include 'struct.inc' ; struct declaration 
EXTRN   '_SpiReg'               AS      SpiReg:word ; SpiReg declaration 

lea     esi, [SpiReg]
mov     [esi+SpiRegStruct.PreOp0], al

    


Thanks.

Kevin Zheng
Post 08 Sep 2006, 00:45
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