[A83] Re: tst + tstio instructions
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[A83] Re: tst + tstio instructions
>> And how about jp m,xxxx ? And what's the use of ld a,a ?
>jp if minus (-127<a<0)
>
>ld a,a (and ld b,b c,c d,d ...) is just a result of the way the
instructions
>are made up, rewad the z80 manual (users guide) from zilog
How stupid.
>> RET C D8 1 NOP 1 ;ret if carry (whatever it is)
>Carry means, addition/subtration/cp went past zero
Ah. I think I understand.
>> RET M F8 1 NOP 1 ;?
>see jp m,xxxx
>> RET NC D0 1 NOP 1 ;ret if not carry
>true
>> RET NZ C0 1 NOP 1 ;ret if not zero
>true
>> RET P F0 1 NOP 1 ;?
>ret if 0<a<128
>> RET PE E8 1 NOP 1 ;?
>Parity even
>> RET PO E0 1 NOP 1 ;?
>Parity odd
>> RET Z C8 1 NOP 1 ;ret if zero
Thanks you too.
>> >You probably mean that if it contains a 2 at the end, it's junk to us...
>> >
>> >Includes OUT0, OTIM* OTDM*, (SLP), [
>> >
>> >but
>> >IND, INDR, INI and INIR don;t have that (yeah, I found more insturctions
>> :-)
>> >
>> >What do they do?
>>
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