Z8S180 Zilog., Z8S180 Datasheet - Page 89

• Manufacturer Part Number: Z8S180
• Description: ENHANCED Z180 MICROPROCESSOR
• Manufacturer: Zilog.

74
UM005001-ZMP0400
Z 8018x Fam il y
M PU Us e r M anual
A0
D0
MREQ
–
–
NMI
A19
WR
Phi
RD
D7
MI
Last MC
Figure 34.
T1
NMI
NMI Use
T1
Program
NMI acknowledge cycle
Main
T3
PC
Ti
EF1
PCL
PCH
T1
EF1
0
PCH
PCL
T1
PC is pushed onto stack
(SP)
(SP+1)
EF2
EF2
(SP-1)
EF1
T2
(SP-2)
SP-1
PCH
T3
T1
T2
SP-2
PCL
T3
0066H
T1 T2 T3
RETN
Restart from 0066H
Instruction
Op Code fetch
0066H
NMI
Interrupt Service
Program