7Deoh  -Xps &Doo Dqg 5Hwxuq *Urxs - ZiLOG Z80 User Manual

7DEOH  -XPS &DOO DQG 5HWXUQ *URXS
JUMP JP
JUMP JR
JUMP JP
CALL
Decrement B, Jump
If Non Zero DJNZ
Return RE
Return From
INT RETI
Return From
Non Maskable
INT RETN
7KH LQVWUXFWLRQ
E\WH UHODWLYH MXPS LQVWUXFWLRQ GHFUHPHQWV WKH % UHJLVWHU DQG WKH MXPS
RFFXUV LI WKH % UHJLVWHU KDV QRW EHHQ GHFUHPHQWHG WR ]HUR 7KH UHODWLYH
GLVSODFHPHQW LV H[SUHVVHG DV D VLJQHG WZR¶V FRPSOHPHQW QXPEHU $
VLPSOH H[DPSOH RI LWV XVH LV
$GGUHVV
N, N+1
N+2 to N+9
N+10,N+11
N + 12
80
8‚qv‡v‚
Un-
Cond.
IMMED. nn C3
EXT. n
n
RELATIVE PC+e 18
e-2
Register (HL) EB
INDIR.
(IX) DD
E9
(IY) FD
E9
IMMED. nn CD
EXT. n
n
RELATIVE PC+e
REGISTER (SP) C9
INDIR. (SP+1)
ED
4D
ED
45
LV XVHG WR IDFLOLWDWH SURJUDP ORRS FRQWURO 7KLV WZR
DJNZ
,QVWUXFWLRQ
LD B, 7
(Perform a sequence of instructions) : loop to be performed 7 times
DJNZ -8
(Next Instruction)
Carry Non Zero Non
Carry Zero
D8 D2 CA C2
n n n n
n n n n
38 30 28 20
e-2 e-2 e-2 e-2
DC D4 CC C4
n n n n
n n n n
D8 D0 C8 C0
&RPPHQWV
: set B register to count of 7
: to jump from N+12 to N+2
= &38 ,QVWUXFWLRQ 'HVFULSWLRQ
< %27
7UGT U /CPWCN
Parity Parity Sign Sign
Even Odd Neg Pos
EA E2 FA F2
n n n n
n n n n
EC E4 FC F4
n n n n
n n n n
E8 E0 F8 F0

Reg
ž
B 0
10
e-2