Figure 34. nmi use – Zilog Z80180 User Manual
Page 89
Z8018x
Family MPU User Manual
74
UM005003-0703
Figure 34. NMI Use
Main
Program
NMI
EF1
0
PCH
EF1
PCL
PCL
PCH
NMI
Interrupt Service
Program
0066H
RETN
®
(SP-2)
®
(SP-1)
®
EF1
®
EF2
¬
EF2
¬
(SP)
¬
(SP+1)
Phi
A0
–
A19
WR
RD
MREQ
D0
–
D7
MI
PCH
PCL
Instruction
Last MC
NMI acknowledge cycle
PC is pushed onto stack
Restart from 0066H
Op Code fetch
PC
SP-1
SP-2
0066H
NMI
T1
T3
Ti
T1
T1
T2
T3
T1
T2
T3
T1
T1 T2
T3