Re: A83: A few Z80 codes in need help with
[Prev][Next][Index][Thread]
Re: A83: A few Z80 codes in need help with
> CA**** : Is this jp,z refering to the address ****?
Yes...
> CC**** : I know you replace the *'s with an
> address, but what does CC do?
call z,****
It push pc to the stack, then jp's to ****. When it encounters a "ret"
(C9) command it pops pc, and such goes back to the next byte after the
call
> 18** : I have no idea...
jr **
Relative Jump... -127 to 127 bytes away from the jr (Acts like jp but
smaller)
> 237E : Again, no idea
Actually, they're seperate commands
23 is inc hl
7E is ld a,(hl)
> C3**** : Another jump of some sort, or is this
> mean call,z ****h?
Non-conditional jump... jp ****
> D602 : I have no idea.
It is D6**... "sub **", which in this case it is subtract 2
> BE****** : I have no idea (again)
BE is "cp (hl)"
The ****** are some other code
> 7C82 and 7D82 : No idea.
They're seperate commands here too...
7C is "ld a,h"
7D is "ld a,l"
82 is "add a,d"
BTW, why are you looking at bytes... Get a disassembler or something,
but source code is much easy to apply to learning than the actual bytes
since the commands are much harder to read as bytes... oh, you can get a
disassembler at ticalc.org and you can also get a opcode table from
ti-files.org (Probably at ticalc.org too).
--
Scott "_Wrath_" Dial
homosapian@geocities.com
ICQ#3608935
http://www.geocities.com/~homosapian/
References: