Struct Button 

pub struct Button<'a> { /* private fields */ }

Available on target_os=none only.

A device abstraction for a button with debouncing and press duration detection.

Hardware Requirements

The button can be wired in two ways:

• PressedTo::Voltage: Button connects pin to 3.3V when pressed (uses pull-down)
• PressedTo::Ground: Button connects pin to GND when pressed (uses pull-up)

Important: Pico 2 (RP2350) has a known silicon bug (erratum E9) with pull-down resistors that can leave the pin reading HIGH after release. Wire buttons to GND and use PressedTo::Ground on Pico 2.

Usage

Use wait_for_press() when you only need a debounced press event. It returns on the down edge and does not wait for release.

Use wait_for_press_duration() when you need to distinguish short vs. long presses. It returns as soon as it can decide, so long presses are reported before the button is released.

Example

use device_envoy::button::{Button, PressDuration, PressedTo};

async fn example(p: embassy_rp::Peripherals) {
    let mut button = Button::new(p.PIN_13, PressedTo::Ground);

    // Wait for a press without measuring duration.
    button.wait_for_press().await;

    // Measure press durations in a loop
    loop {
        match button.wait_for_press_duration().await {
            PressDuration::Short => {
                // Handle short press
            }
            PressDuration::Long => {
                // Handle long press (fires before button is released)
            }
        }
    }
}

Implementations

impl<'a> Button<'a>

pub fn new<P: Pin>(pin: Peri<'a, P>, pressed_to: PressedTo) -> Self

Creates a new Button instance from a pin.

The pin is configured based on the connection type:

• PressedTo::Voltage: Uses internal pull-down (button to 3.3V)
• PressedTo::Ground: Uses internal pull-up (button to GND)

pub fn is_pressed(&self) -> bool

Returns whether the button is currently pressed.

pub async fn wait_for_press(&mut self)

Waits for the next press (button goes down, debounced). Does not wait for release.

See Button for usage example

pub async fn wait_for_press_duration(&mut self) -> PressDuration

Waits for the next press and returns whether it was short or long (debounced).

Returns as soon as it can decide, so long presses are reported before release.

See Button for usage example

pub async fn wait_for_release(&mut self)

Waits until the button is released (debounced).