AT91SAM7S32-AI ATMEL [ATMEL Corporation], AT91SAM7S32-AI Datasheet - Page 127

• Manufacturer Part Number: AT91SAM7S32-AI
• Description: AT91 ARM Thumb-based Microcontrollers
• Manufacturer: ATMEL [ATMEL Corporation]

Advanced Interrupt Controller (AIC)
Overview
Block Diagram
Application
Block Diagram
6071A–ATARM–28-Oct-04
The Advanced Interrupt Controller (AIC) is an 8-level priority, individually maskable, vectored
interrupt controller, providing handling of up to thirty-two interrupt sources. It is designed to
substantially reduce the software and real-time overhead in handling internal and external
interrupts.
The AIC drives the nFIQ (fast interrupt request) and the nIRQ (standard interrupt request)
inputs of an ARM processor. Inputs of the AIC are either internal peripheral interrupts or exter-
nal interrupts coming from the product's pins.
The 8-level Priority Controller allows the user to define the priority for each interrupt source,
thus permitting higher priority interrupts to be serviced even if a lower priority interrupt is being
treated.
Internal interrupt sources can be programmed to be level sensitive or edge triggered. External
interrupt sources can be programmed to be positive-edge or negative-edge triggered or high-
level or low-level sensitive.
The fast forcing feature redirects any internal or external interrupt source to provide a fast
interrupt rather than a normal interrupt.
Figure 43. Block Diagram
Figure 44. Description of the Application Block
Applications
Standalone
Embedded Peripherals
Embedded
PeripheralEE
Embedded
Peripheral
Embedded
Peripheral
IRQ0-IRQn
FIQ
OS Drivers
General OS Interrupt Handler
Advanced Interrupt Controller
AT91SAM7S32 Preliminary
Thirty-two
Sources
OS-based Applications
Up to
AIC
RTOS Drivers
APB
External Peripherals
(External Interrupts)
Hard Real Time Tasks
nFIQ
nIRQ
Processor
ARM
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