Z8018x Family
MPU User Manual
77
disabling all maskable interrupts. The interrupt service routine normally
terminates with the EI (Enable Interrupts) instruction followed by the
RETI (Return from Interrupt) instruction, to reenable the interrupts.
Figure 37 depicts the use of INT0 (Mode 1) and RETI for the Mode 1
interrupt sequence.
Figure 37. INT0 Mode 1 Interrupt Sequence
0
PCH
PCL
®
®
®
EF1, EF2
(SP-1)
(SP-2)
0038H
Main
Program
INT0 (Mode 1)
Interrupt Service
Program
INT0
(Mode 1)
PCL
PCH
¬
¬
(SP)
(SP+1)
E1 (1
RETI
® 1EF1, 1EF2)
Figure 38 illustrates INT0 Mode 1 Timing.
UM005001-ZMP0400
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