
UM008007-0715 Jump, Call, and Return
Z80 CPU
User Manual
57
Descriptions of the Jump Group instructions begin on page 258.
Three types of Register Indirect jumps are also included. These instructions are imple-
mented by loading the register pair HL or one of the index registers IX or IY directly into
the Program Counter. This feature allows for program jumps to be a function of previous
calculations.
A Call is a special form of a jump in which the address of the byte following the call
instruction is pushed onto the stack before the jump is made. A return instruction is the
reverse of a call because the data on the top of the stack is popped directly into the Pro-
Table 14. Jump, Call, and Return Group
Condition
Un-
Cond. Carry
Non-
Carry Zero
Non-
Zero
Parity
Even
Parity
Odd
Sign
Neg
Sign
Pos
Reg
B¹0
JUMP
JP
IMMED.
EXT.
nn
C3
n
n
D8
n
n
D2
n
n
CA
n
n
C2
n
n
EA
n
n
E2
n
n
FA
n
n
F2
n
n
JUMP
JR
RELATIVE PC+e
18
e–2
38
e–2
30
e–2
28
e–2
20
e–2
JUMP
JP
Register
INDIR.
(HL) EB
(IX)
DD
E9
(IY)
FD
E9
CALL
IMMED.
EXT.
nn
CD
n
n
DC
n
n
D4
n
n
CC
n
n
C4
n
n
EC
n
n
E4
n
n
FC
n
n
F4
n
n
D
ecrement B,
Jump If Non-Zero
DJNZ
RELATIVE PC+e
10
e–2
Return
RE
REGISTER
INDIR.
(SP)
(SP+1)
C9 D8 D0 C8 C0 E8 E0 F8 F0
Return From
Interrupt
RETI
ED
4D
Return From Non-
Maskable
Interrupt
RETN
ED
45
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