Renesas Stereo System SH7709S User Manual
Rev. 5.00, 09/03, page 117 of 760
Section 6 Interrupt Controller (INTC)
6.1
Overview
The interrupt controller (INTC) ascertains the priority of interrupt sources and controls interrupt
requests to the CPU. The INTC registers set the order of priority of each interrupt, allowing the
user to process interrupt requests according to the user-set priority.
requests to the CPU. The INTC registers set the order of priority of each interrupt, allowing the
user to process interrupt requests according to the user-set priority.
6.1.1
Features
The INTC has the following features:
•
16 levels of interrupt priority can be set: By setting the five interrupt-priority registers, the
priorities of on-chip peripheral module, IRQ, and PINT interrupts can be selected from 16
levels for individual request sources.
priorities of on-chip peripheral module, IRQ, and PINT interrupts can be selected from 16
levels for individual request sources.
•
NMI noise canceler function: An NMI input-level bit indicates the NMI pin state. By reading
this bit in the interrupt exception service routine, the pin state can be checked, enabling it to be
used as a noise canceler.
this bit in the interrupt exception service routine, the pin state can be checked, enabling it to be
used as a noise canceler.
•
External devices can be notified that an interrupt has been received (
IRQOUT): When the
SH7709S has released the bus, the external bus master can be notified that an external
interrupt, an on-chip peripheral module interrupt, or a memory refresh request has occurred,
enabling the bus to be requested.
interrupt, an on-chip peripheral module interrupt, or a memory refresh request has occurred,
enabling the bus to be requested.