Difference between revisions of "Z80 wait instructions"

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Z80 instruction set that don't change registers value (except for F register):
 
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! Inst. !! Wait<br/>CC !! Size<br/>(bytes) !! Flag modification
 
! Inst. !! Wait<br/>CC !! Size<br/>(bytes) !! Flag modification

Revision as of 23:09, 2 March 2024

Z80 instruction set that don't change registers value (except for F register):

Inst. Wait
CC
Size
(bytes)
Flag modification
NOP 5 1 None
OR 0 8 2 C and N flags cleared, P/V detects parity, and rest are modified by definition.
NOP
NOP
10 2 None
LD R,A 11 2  ???
NOP
OR 0
13 3 C and N flags cleared, P/V detects parity, and rest are modified by definition.
BIT 0,(HL) 14 2 Opposite of the bit #0 is written into the Z flag. C is preserved, N is reset, H is set, and S and P/V are undefined.
NOP
NOP
NOP
15 3 None
CP (IY+0) 21 3  ???
BIT 0,(IY+0) 22 4  ???