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5.1.2 Block Diagram
Figure 5-1 shows a block diagram of the interrupt controller.
ISCR
IER
IPRA, IPRB
.
.
.
OVF
TME
ADI
ADIE
.
.
.
.
.
.
.
CPU
CCR
I
UI
UE
SYSCR
I:
IER:
IPRA:
IPRB:
ISCR:
ISR:
SYSCR:
UE:
UI:
NMI
input
IRQ input
IRQ input
section ISR
Interrupt controller
Priority
decision logic
Interrupt
request
Vector
number
Interrupt mask bit
IRQ enable register
Interrupt priority register A
Interrupt priority register B
IRQ sense control register
IRQ status register
System control register
User bit enable
User bit/interrupt mask bit
Legend
Figure 5-1 Interrupt Controller Block Diagram