Nios II Classic Software Developer’s Handbook

ID 683282
Date 5/14/2015
Public
Document Table of Contents

8.2. Nios II Interrupt Service Routines

Software often communicates with peripheral devices using hardware interrupts. When a peripheral asserts its IRQ, it diverts the processor’s normal execution flow. When such an interrupt occurs, an appropriate ISR must handle this interrupt and return the processor to its pre-interrupt state on completion.

When you create a board support package (BSP) project, the build tools include all needed device drivers. You do not need to write HAL ISRs unless you are interfacing to a custom peripheral. For reference purposes, this section describes the framework provided by HAL BSPs for handling hardware interrupts.

For examples of HAL ISRs, refer to existing handlers for Altera components.

For more information about the Altera-provided HAL handlers, refer to the "Developing Programs Using the Hardware Abstraction Layer" section.