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marek



Joined: 21 Mar 2008
Posts: 5
marek
Hello, I have problems with the following code (especially the line highlighted in red). The code assembles, but does not show anything.
If I do "mov al, 72", I can see yellow 'H' on the screen, so I cannot understand why the below code doesn't work.

; display string
mov ax, 0xb800
mov es, ax
xor di,di
; 0xb800:0000 - address of the first char on the screen

mov ah, 14 ; yellow

repeat strlen
mov al, byte [mystring+%-1]
stosw
end repeat

hlt

mystring db 'Hello world !!!'
strlen=$-mystring[/size]

Thanks,
Marek.
Post 25 Mar 2008, 13:22
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revolution
When all else fails, read the source


Joined: 24 Aug 2004
Posts: 17714
Location: In your JS exploiting you and your system
revolution
Try using a CS override
Code:
 mov al, byte [cs:mystring+%-1]    
or set DS
Code:
mov ax,cs
mov ds,ax    
Post 25 Mar 2008, 13:28
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marek



Joined: 21 Mar 2008
Posts: 5
marek
Revolution, you are wonderful !!!

Thank you for your incredibly quick and very helpful answers !!!

Marek.
Post 25 Mar 2008, 13:56
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revolution
When all else fails, read the source


Joined: 24 Aug 2004
Posts: 17714
Location: In your JS exploiting you and your system
revolution
Glad to be of service.
Post 25 Mar 2008, 14:34
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