Re: A86: more info needed on ld command
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Re: A86: more info needed on ld command
Yeah, anything in () means THE ADDRESS OF, as in C's & address of operator.
HL is basically a 16-bit register that can be used as both a 16-bit register
and
16-bit pointer to an 8-bit datatype.
----------------
ld HL, 1000h
ld (HL), 50
Stores the decimal number 50 into the memory location 1000h. I believe this
is correct.
------------------
- Cyber Optic
>On Thu, 11 Sep 1997, Butler Family wrote:
>
>> > ld (hl),nn loads nn into the memory location whose
>> > address is stored in hl
>>
>> what is the use of loading it into the memory location if u can do the
>> basically same thing w/o parentheses? or would it keep the hl from
>> moving its location in the memory?and one last question what would it do
>> if u did ld nn,(hl)? would it make nn equal to the memory location or
>> save it as hl and have be where hl was?
>
>
>I think there's a fundamental misunderstanding here, but I'll try to
>explain clearly.
>
>"LD (HL),nn" and "LD HL,nnnn" are NOT basically the same thing. HL is a
>register, which is a storage space completely separate from memory. If
>you're used to programming in almost any high-level language, you're
>probably getting confused by thinking of HL as a variable. Don't.
>
>"LD HL,nnnn" stores the value nnnn into the register HL.
>"LD (HL),nn" stores the value nn into the memory address HL points to
>
>Here's an example to help sort things out:
>
> LD HL,$C008
> LD (HL),$2A
>
>After the first instruction, HL=$C008. After the second instruction, byte
>$C008 in RAM holds the value $2A.
>
>"LD nn,HL" is not a valid instruction, because you can't store into a
>constant.
>
>I hope this has been beneficial.