Internal Interrupts; Interrupt Exception Vector Table - Hitachi H8S/2338 Series Hardware Manual

Figure 3-3 shows the timing of setting IRQnF.
ø
IRQn
input pin
IRQnF
The vector numbers for IRQ7 to IRQ0 interrupt exception handling are 23 to 16.
Detection of IRQ7 to IRQ0 interrupts does not depend on whether the relevant pin has been set for
input or output. Therefore, when a pin is used as an external interrupt input pin, do not clear the
corresponding DDR bit to 0 and use the pin as an I/O pin for another function. The pins that can
be used for IRQ4 to IRQ7 interrupt input can be switched by means of the IRQPAS bit in SYSCR.
The switched pins differ from model to model; see the reference manual for the relevant model for
details.
3.3.2

Internal Interrupts

There are 52 sources for internal interrupts from on-chip supporting modules.
• For each on-chip supporting module there are flags that indicate the interrupt request status,
and enable bits that select enabling or disabling of these interrupts. If both of these are set to 1
for a particular interrupt source, an interrupt request is issued to the interrupt controller.
• The interrupt priority level can be set by means of IPR.
• The DMAC and DTC can be activated by a TPU, SCI, or other interrupt request. When the
DMAC or DTC is activated by an interrupt, the interrupt control mode and interrupt mask bits
have no effect.
3.3.3

Interrupt Exception Vector Table

Table 3-4 shows interrupt exception handling sources, vector addresses, and interrupt priorities.
For default priorities, the lower the vector number, the higher the priority.
Priorities among modules can be set by means of IPR. The situation when two or more modules
are set to the same priority, and priorities within a module, are fixed as shown in table 3-4.
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Figure 3-3 Timing of Setting IRQnF