From: NoEmail@nospicedham.trraxvfeqa.prg
On Tue, 24 Apr 2018 16:20:47 -0700
bilsch wrote:
> On 04/24/2018 04:04 AM, Bartc wrote:
> > On 24/04/2018 10:48, bilsch wrote:
> >> The boot sector jumps to this code.
> >> It should print junk6789 but prints only j
> >> Why it not print junk6789 ? TIA. Bill S.
> >
> >>
> >> pbuf times 80 db 0
> >> string db 'junk'
> >
> >> mov si,pbuf
> >> mov di,string
> >> lup8: mov al,[di]
> >> mov byte[si],al
> >> inc si
> >> inc di
> >> cmp di,4
> >> jbe lup8
> >
> > di starts at label 'string'. Is that address 0? If not then
> > comparing it with 4 looks odd.
> >
> > If string has an address of at least 80 as seems likely, then this
> > will compare false and only one character is copied to the buffer.
> >
>
> Indeed. Here's the fix to the code above. It prints 'junk' but not
> 'junk6789'. My real question is why doesn't it print the 6789 part?
>
> string db 'junk',0
>
> mov si,pbuf
> mov di,string
> lup8: mov al,[di]
> cmp al,0
> jz ovr1
> move byte[si],al
> inc si
> inc di
> jmp lup8
> ovr1:
>
Why wasn't this your fix?
mov si,pbuf
mov di,string
lup8: mov al,[di]
mov byte[si],al
inc si
inc di
cmp di,4+string
jbe lup8
Rod Pemberton
--
I believe in the right to life. That's why I oppose gun control.
--- SoupGate-Win32 v1.05
* Origin: you cannot sedate... all the things you hate (1:229/2)
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