GMS81C1404 Datasheet, PDF (63/93 Pages) Hynix Semiconductor – 8-BIT SINGLE-CHIP MICROCONTROLLERS

GMS81C1404/GMS81C1408
Main Program
service
TIMER 1
service
Occur
TIMER1 interrupt
enable INT0
disable other
EI
Occur
INT0
INT0
service
enable INT0
enable other
In this example, the INT0 interrupt can be serviced without any
pending, even TIMER1 is in progress.
Because of re-setting the interrupt enable registers IENH,IENL
and master enable “EI” in the TIMER1 routine.
Figure 17-5 Execution of Multi Interrupt
Example: Even though Timer1 interrupt is in progress,
INT0 interrupt serviced without any suspend.
TIMER1: PUSH
PUSH
PUSH
LDM
LDM
EI
:
:
:
A
X
Y
IENH,#80H
IENL,#0
;Enable INT0 only
;Disable other
;Enable Interrupt
:
:
:
LDM
LDM
POP
POP
POP
RETI
IENH,#0FFH
IENL,#0F0H
Y
X
A
;Enable all interrupts
June. 2001 Ver 1.2
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