HD6412373R RENESAS [Renesas Technology Corp], HD6412373R Datasheet - Page 188

• Manufacturer Part Number: HD6412373R
• Description: Renesas 16-Bit Single-Chip Microcomputer H8S Family/H8S/2300 Series
• Manufacturer: RENESAS [Renesas Technology Corp]

Section 5 Interrupt Controller
5.4
5.4.1
There are seventeen external interrupts: NMI and IRQ15 to IRQ0. These interrupts can be used to
restore the chip from software standby mode.
NMI Interrupt: Nonmaskable interrupt request (NMI) is the highest-priority interrupt, and is
always accepted by the CPU regardless of the interrupt control mode or the status of the CPU
interrupt mask bits. The NMIEG bit in INTCR can be used to select whether an interrupt is
requested at a rising edge or a falling edge on the NMI pin.
IRQ15 to IRQ0 Interrupts: Interrupts IRQ15 to IRQ0 are requested by an input signal at pins
IRQ15 to IRQ0. Interrupts IRQ15 to IRQ0 have the following features:
• Using ISCR, it is possible to select whether an interrupt is generated by a low level, falling
• Enabling or disabling of interrupt requests IRQ15 to IRQ0 can be selected with IER.
• The interrupt priority level can be set with IPR.
• The status of interrupt requests IRQ15 to IRQ0 is indicated in ISR. ISR flags can be cleared to
When IRQ15 to IRQ0 interrupt requests occur at low level of IRQn, the corresponding IRQ
should be held low until an interrupt handling starts. Then the corresponding IRQ should be set to
high in the interrupt handling routine and clear the IRQnF bit (n = 0 to 15) in ISR to 0. Interrupts
may not be executed when the corresponding IRQ is set to high before the interrupt handling
starts.
Detection of IRQ15 to IRQ0 interrupts does not depend on whether the relevant pin has been set
for input or output. However, when a pin is used as an external interrupt input pin, do not clear the
corresponding DDR to 0 and use the pin as an I/O pin for another function.
A block diagram of interrupts IRQ15 to IRQ0 is shown in figure 5.2.
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REJ09B0109-0700
edge, rising edge, or both edges, at pins IRQ15 to IRQ0.
0 by software.
Interrupt Sources
External Interrupts