Re: A83: Got another one for 'ya


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Re: A83: Got another one for 'ya




Hehe... This won't either works, as xor reg does A = A^REG ( the ^ means xor ).
So it only affect A.

On the 83, you can only do xor a to clear a register. xor h will do A = A xor H,
and won't clear anything.

You can try :
xor a \ ld h, a \ ld l, a  (stupid : 3 bytes, 12 clocks cycles )

or :
or a \ sbc hl, hl

not so good : 3 bytes, 19 cycles...

or use ld hl, 0 ( 3 bytes, 10 cycles ) ! This remains the fastest, incredible !

- Florent

-----Message d'origine-----
De : Phelan Wolf <gwatford@worldnet.att.net>
À : assembly-83@lists.ticalc.org <assembly-83@lists.ticalc.org>
Date : dimanche 14 juin 1998 18:59
Objet : Re: A83: Got another one for 'ya


>
>oops, xor h    xor l
>only 2 clocks faster and 1 bytes smaller
>
>Olle Hedman wrote:
>
>> At 11:35 1998-06-14 -0700, Wolf wrote:
>> >
>> >1). instead of    ld hl,0    do    xor hl    it is 6 clocks faster and 2
>> bytes smaller
>>
>> sorry, but you can't xor hl...
>>
>> //Olle
>
>
>


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