HD6433044 Hitachi Semiconductor, HD6433044 Datasheet - Page 109

• Manufacturer Part Number: HD6433044
• Description: (HD64 Series) Hitachi Single-Chip Microcomputer
• Manufacturer: Hitachi Semiconductor

5.3 Interrupt Sources
The interrupt sources include external interrupts (NMI, IRQ
5.3.1 External Interrupts
There are seven external interrupts: NMI, and IRQ
IRQ
NMI: NMI is the highest-priority interrupt and is always accepted, regardless of the states of the
I and UI bits in CCR. The NMIEG bit in SYSCR selects whether an interrupt is requested by the
rising or falling edge of the input at the NMI pin. NMI interrupt exception handling has vector
number 7.
IRQ
The IRQ
•
•
•
Figure 5-2 shows a block diagram of interrupts IRQ
IRQn
Note: n = 5 to 0
2
ISCR settings can select whether an interrupt is requested by the low level of the input at pins
IRQ
IER settings can enable or disable the IRQ
assigned by four bits in IPRA (IPRA7 to IPRA4).
The status of IRQ
cleared to 0 by software.
0
can be used to exit software standby mode.
to IRQ
0
input
0
to IRQ
to IRQ
5
Interrupts: These interrupts are requested by input signals at pins IRQ
5
5
, or by the falling edge.
interrupts have the following features.
Figure 5-2 Block Diagram of Interrupts IRQ
0
to IRQ
sense circuit
5
Edge/level
IRQnSC
interrupt requests is indicated in ISR. The ISR flags can be
Clear signal
0
95
to IRQ
0
0
to IRQ
to IRQ
S
R
5
interrupts. Interrupt priority levels can be
IRQnF
5
0
. Of these, NMI, IRQ
5
.
to IRQ
Q
IRQnE
5
0
) and 30 internal interrupts.
to IRQ
5
0
IRQn interrupt
request
, IRQ
0
1
to IRQ
, and
5
.