Module interrupt 

Interrupt support

This module contains code to configure and handle peripheral interrupts.

Overview

Peripheral interrupt requests are not handled by the CPU directly. Instead, they are routed through the interrupt matrix, which maps peripheral interrupts to CPU interrupts. There are more peripheral interrupt signals than CPU interrupts, and multiple peripheral interrupts can be routed to the same CPU interrupt. A set of CPU interrupts are configured to run a default handler routine, which polls the interrupt controller and calls the appropriate handlers for the pending peripheral interrupts.

This default handler implements interrupt nesting - meaning a higher Priority interrupt can preempt a lower priority interrupt handler. The number of priorities is a chip-specific detail.

Usage

Peripheral drivers manage interrupts for you. Where appropriate, a set_interrupt_handler function is provided, which allows you to register a function to handle interrupts at a priority level of your choosing. Interrupt handler functions need to be marked by the [#[handler]] attribute. These drivers also provide listen and unlisten functions that control whether an interrupt will be generated for the matching event or not. For more information and examples, consult the documentation of the specific peripheral drivers.

If you are writing your own peripheral driver, you will need to first register interrupt handlers using the [peripheral singletons’] bind_X_interrupt functions. You can use the matching enable and disable functions to control the peripheral interrupt in the interrupt matrix, or you can, depending on the peripheral, set or clear the appropriate enable bits in the int_ena register.

[#[handler]]: crate::handler [peripheral singletons’]: crate::peripherals::I2C0

Software interrupts

The software module implements software interrupts using peripheral interrupt signals.

Modules

softwareunstable

Software Interrupts

Structs

InterruptHandlerunstable

An interrupt handler

InterruptStatusunstable

Representation of peripheral-interrupt status bits.

InterruptStatusIteratorunstable

Iterator over set interrupt status bits

IsrCallbackunstable

Represents an ISR callback function

TrapFrameunstable

Registers saved in trap handler

Enums

CpuInterruptunstable

Enumeration of available CPU interrupts.

DirectBindableCpuInterrupt

Enumeration of CPU interrupts available for direct binding.

ElevatedRunLevel

Interrupt run levels.

InterruptKindunstable

Interrupt kind

Priority

Interrupt priority levels.

PriorityErrorunstable

Priority Level Error

RunLevel

Represents the priority level of running code.

Constants

DEFAULT_INTERRUPT_HANDLERunstable

Default (unhandled) interrupt handler

Traits

InterruptConfigurableunstable

Trait implemented by drivers which allow the user to set an InterruptHandler

Functions

bind_handlerunstable

Binds the given handler to a peripheral interrupt.

bound_handlerunstable

Returns the currently bound interrupt handler.

disableunstable

Disable the given peripheral interrupt.

enableunstable

Enables a peripheral interrupt at a given priority, using vectored CPU interrupts.

enable_directunstable

Enable an interrupt by directly binding it to an available CPU interrupt

wait_for_interruptunstable

Wait for an interrupt to occur.