Re: A83: program...
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Re: A83: program...
>>PS: What are you allowed to use the IX and IY registers for
>
>IX and IY are index register and can reference 256 bytes of the value of
>IX/IY. Such as:
>ld ix, $8888
>ld hl, (IX+1)
>
>this would put $8889 in hl... Same way with iy. The calculator uses IX
>it for system flags and IY can't be used on the calc unless you disable
>the interrupts first. I don't remember what IY was for, anyone?
it doesn't put $8889 in hl.. it loads the value at memoryposition $8889
into hl. (that is what the "(" and ")" stands for.. )
and wasn't it IY that was initialised på ti-OS to point to the systemflags?
that is why you can't change IY unless you disable interupts.
IX is free to use anytime.
//Olle
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