HD6417641 RENESAS [Renesas Technology Corp], HD6417641 Datasheet - Page 290

• Manufacturer Part Number: HD6417641
• Manufacturer: RENESAS [Renesas Technology Corp]

Section 10 Interrupt Controller (INTC)
10.5.2
When handling multiple interrupts, an interrupt handler should include the following procedures:
1. Branch to a specific interrupt handler corresponding to a code set in INTEVT2. The code in
2. Clear the interrupt source in each specific handler.
3. Save SSR and SPC to memory.
4. Clear the BL bit in SR, and set the accepted interrupt level in the interrupt mask bits in SR.
5. Handle the interrupt.
6. Execute the RTE instruction.
When these procedures are followed in order, an interrupt of higher priority than the one being
handled can be accepted after clearing BL in step 4. Figure 10.2 shows a sample interrupt
operation flowchart.
10.6
10.6.1
Use IRQ0/IRQ1 carefully. The USB bus power control uses the interrupt control logic block for
IRQ0/IRQ1.
For the details about the USB bus power control, refer to section 20, USB Function Module.
10.6.2
As described in section 10.5.1, Interrupt Sequence, clear the interrupt source flags in the interrupt
handler.
To avoid accepting an interrupt source flag that has been cleared, read the flag and then, execute
the RTE instruction.
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INTEVT2 can be used as an offset for branching to the specific handler.
Multiple Interrupts
Notes on Use
Notes on USB Bus Power Control
Timing to Clear an Interrupt Source