Module interrupt

Interrupt support

Overview

The interrupt driver is a crucial module for ESP chips. Its primary purpose is to manage and handle interrupts, which are asynchronous events requiring immediate attention from the CPU. Interrupts are essential in various applications, such as real-time tasks, I/O communications, and handling external events like hardware signals.

The core functionality of the interrupt driver revolves around the management of interrupts. When an interrupt occurs, it temporarily stops the ongoing CPU operations, saves its current state, and starts executing the corresponding interrupt service routine (ISR). The interrupt service routine is a user-defined function that performs the necessary actions to handle the specific interrupt. Once the ISR is executed, the driver restores the saved CPU state and resumes normal program execution.

In scenarios where multiple interrupts may occur simultaneously, the interrupt driver determines the priority of each interrupt. This prioritization ensures that critical or high-priority tasks are handled first. It helps prevent delays in time-sensitive applications and allows the system to allocate resources efficiently. This functionality is provided and implemented by the priority enum.

Example

#[entry]
fn main() -> ! {
    ...
    critical_section::with(|cs| SWINT.borrow_ref_mut(cs).replace(sw_int));

    interrupt::enable(
        peripherals::Interrupt::FROM_CPU_INTR0,
        interrupt::Priority::Priority1,
    )
    .unwrap();

    loop {}
}

#[interrupt]
fn FROM_CPU_INTR0() {
    esp_println::println!("SW interrupt0");
    critical_section::with(|cs| {
        SWINT
            .borrow_ref_mut(cs)
            .as_mut()
            .unwrap()
            .reset(SoftwareInterrupt::SoftwareInterrupt0);
    });
}

Structs

TrapFrame

Registers saved in trap handler

Enums

CpuInterrupt

Enumeration of available CPU interrupts. It is possible to create a handler for each of the interrupts. (e.g. interrupt3)

Error

Interrupt Error

InterruptKind

Interrupt kind

Priority

Interrupt priority levels.

Functions

clear

Clear a CPU interrupt

disable

Disable the given peripheral interrupt.

enable

Enables a interrupt at a given priority

enable_cpu_interrupt^⚠

Enable a CPU interrupt

get_status

Get status of peripheral interrupts

interrupt1^⚠

interrupt2^⚠

interrupt3^⚠

interrupt4^⚠

interrupt5^⚠

interrupt6^⚠

interrupt7^⚠

interrupt8^⚠

interrupt9^⚠

interrupt10^⚠

interrupt11^⚠

interrupt12^⚠

interrupt13^⚠

interrupt14^⚠

interrupt15^⚠

interrupt16^⚠

interrupt17^⚠

interrupt18^⚠

interrupt19^⚠

map^⚠

Assign a peripheral interrupt to an CPU interrupt.

set_kind

Set the interrupt kind (i.e. level or edge) of an CPU interrupt

set_priority^⚠

Set the priority level of an CPU interrupt