A89: Re: storing from d1 to a0


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A89: Re: storing from d1 to a0




I tried it that way but for some reason it's not working for me.  The
following code should equal the same thing, shouldn't it?

 move.l #t_stat,a0
 move.w d0,(a0)

and

 move.l #s1stat,a0
 move.w d0,(a0)

s1stat dc.w    0
t_stat dc.l   s1stat,s2stat,etc.

but in my program when I try the second one, it works, but if I try the
first one, it doesn't.


----- Original Message -----
From: Zoltan Kocsi <zoltan@bendor.com.au>
To: <assembly-89@lists.ticalc.org>
Sent: Saturday, October 30, 1999 5:52 PM
Subject: A89: storing from d1 to a0


>
>  > I was wondering if it was possible to store something from d1to an
address pointed to by a0.  I tried doing this:
>  >
>  > move.w    d1(a0)
>  >
>  > after having pointed a0 to a variable earlier in the program, but it
didn't work.  The reason I need this is because I am using lookup tables,
and I need to store a variable located in d1 to the address pointed to by
a0, as in the following:
>
> You need a comma as in:
>
>  move.w d1,(a0)
>
> This works. If it doesn't, then you have a wrong value in a0.
>
>  >  move.w scounter,d0
>  >  rol.w #2,d0
>  >  add.l #(t_stat),d0
>  >  move.l d0,a0
>  >
>  >  move.w d1,(a0)
>
> Depending on what you do, that is, how often do you refer to the same
> table, it might be advantageous to use the N8(An,Xn.s) addressing mode.
> The above code, on its own, would be quicker this way:
>
>   move.w scounter,d0
>   move.l #t_stat,a0
>   add.w d0,a0
>   add.w d0,a0
>   move.w d1,(a0)
>
> Suggested reading would be:
>
> MC68000UM/AD, The 68000 User's Manual from Motorola (available in
> PDF format from Motorla's website), or
>
> M68000PM/AD, Programmers Reference Manual, can be ordered from the
> Motorola Literature Center.
>
> Would that be possible to post w/o the HTML extensios ? Nothing
> serious, just asking. Maybe a wordwrap around 72-76 characters ?
>
>
> Regards,
>
> Zoltan
>
>



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