Nios® V Processor Software Developer Handbook

ID 743810
Date 7/08/2024
Public
Document Table of Contents

9.3.1. HAL APIs for Software Interrupt

Intel provides the HAL Software Interrupt API for writing, registering, and managing ISRs. The Nios® V processor supports one software interrupt only.

The interrupt API includes the following types of routines:
  • Routines to register an ISR
  • Routines to manage ISR environment
  • Routines to control ISR behavior
The interrupt API supports the following types of BSPs:
  • Bare-metal HAL BSP
  • Micrium MicroC/OS-II (uC/OS-II) BSP
  • FreeRTOS* BSP

You need to perform the following steps to implement software ISR with HAL software interrupt API:

  1. Create your ISR functions prototype that handles software interrupt.
  2. Ensure your program registers the ISR with the HAL driver by calling alt_niosv_register_msw_interrupt_handler().
  3. Enable software interrupt with alt_niosv_enable_msw_interrupt().
Table 39.  HAL Software Interrupt API Functions
Function Name Description
alt_niosv_register_msw_interrupt handler() Register an interrupt handler to handle software interrupt.
alt_niosv_enable_msw_interrupt() Enables software interrupt.
alt_niosv_disable_msw_interrupt() Disables software interrupt.
alt_niosv_is_msw_interrupt_enabled() Determine if the software interrupt is enabled.
alt_niosv_trigger_msw_interrupt() Generate a software IRQ.
alt_niosv_clear_msw_interrupt() Clear the current software IRQ