Re: A83: Re: Re:
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Re: A83: Re: Re:
The stack pointer points to the memory location in the RAM that is used
for the stack. Now here's a little bit of useless info. By the way,
does anyone know where thestack memory starts and ends
Basically, if there was no push command, you would have to do this:
inc sp ; 2 because the stack locations are 16-bits
inc sp
ld (sp),rr
Pop would be:
ld rr,(sp)
dec sp
dec sp
Call would be:
inc sp
inc sp
ld (sp),pc
jp xxxx ; jp actually being ld pc,xxxx
Ret would basically be:
ld pc,(sp) ; which would actually be impossible, because it would jump
as soon as you
dec sp ; loaded the pc register, so it wouldn't post-decrement the
stack pointer
dec sp
>
>Would someone like to explain the stack pointer in more detail? I
>know
>*roughly* what it does...no, actually I don't :)...
>
>Later,
>
>James Matthews (matthews@tkb.att.ne.jp)
>
>ICQ: 7413754
>http://home.att.ne.jp/gold/tomcat21/index.html
>http://library.advanced.org/18242/
>
>----------
>> From: Scott Dial (Revenant) <homosapian@geocities.com>
>> To: assembly-83@lists.ticalc.org
>> Subject: A83: Re:
>> Date: Sunday, September 13, 1998 9:28 AM
>>
>>
>> Exactly that...
>>
>> sp is a z80 register for the position of stack pointer... so that he
>can
>> return to that exact point later. spbak is defined at the bottom:
>spbak
>> .dw $0000
>>
>> Patrick W Bambrough wrote:
>> >
>> > hey can anyone tell me what this means and if there is an 83
>equivelant??
>> > ld (spbak),sp
>>
>> --
>> Scott Dial
>> revenant_1@hotmail.com
>> ICQ#3608935
>
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