Re: A92: Re: keyb matrix


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Re: A92: Re: keyb matrix




Thank you very much David. Very usefull !
Thank you again.

MP <philhuck@club-internet.fr> <http://mp.i-france.com>


-----Message d'origine-----
De : David Kühling <dkuehlin@hell1og.be.schule.de>
À : assembly-92@lists.ticalc.org <assembly-92@lists.ticalc.org>
Date : lundi 28 septembre 1998 13:19
Objet : Re: A92: Re: keyb matrix


>
>Klaus wrote:
>>
>> ...
>> Getkey:
>> movem.l d0-d1/a0,-(a7)
>> lea keystat(pc),a0
>> move.w #$FFFE,d0
>> move.w #9,d1
>> GetKeys:
>> move.w d0,$600018
>> nop
>> nop
>> nop
>> nop
>> nop
>> nop
>> nop
>> nop
>> nop
>> move.b $60001B,(a0)+
>> rol.w #1,d0
>> dbra.w d1,GetKeys
>> movem.l (a7)+,d0-d1/a0
>> rts
>>
>
>Use
> move.l (a7),(a7)
> move.l (a7),(a7)
> move.l (a7),(a7)
>instead of the NOPs. It's a little bit smaller, since the move-
>instructions take more time.
>Redirection could be done by more effectively by making all
>vectors point to the _same_ rte. (everything else would be
>memory wasting). Instead of redirecting all those ints, you
>could just switch them off by:
>
> move.w #$700,d0
> trap #1 ; switch off interrupts, old state: d0
>
> ... ;(don't change d0!)
>
> trap #1 ; restore interrupts
>