Re: A83: A > Op1


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Re: A83: A > Op1




Well you _could_ try the neg-instruction..

ld a,(speed)
neg
ld (speed),a

//Olle
(Tip of the day: download an z80 instruction set description from ticalc.org)

Marc Puts wrote:
> 
> Sorry, i can't still figure uit what i need to do...
> 
> What I want to do is negate the variable speed. That's all!
> Only if I knew how....
> 
> This is what I tried:
> 
>         call    _zerooop1
>         ld      a,(speed)
>         ld      (op1),a
>         call    _invop1s
>         call    _convop1
>         ld      a,e
>         ld      (speed),a
> 
> Can anybody tell me what's wrong with it?
> (Probably everything)
> 
> Thanx, Marc


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