timed-debouncer

no_std Rust crate for debouncing signals from electrical contacts like push-buttons, rotary switches and alike. The processing uses a time-based generic approach and can therefore be used with any simple numeric type (e.g. bool, u8 or f32).

Usage

Call the update() function with a raw input value, a timestamp tick and a tick count for the debouncing. It will return a processed value that is stable for the configured tick count. The tick value can be of any unit, in practice, using milliseconds is a common recommendation. The required debounce time is dependent on the mechanics of the contacts. Using a value in range of 10-20ms is a good choice for most switches to ensure safe operation.

The debouncer will take the default value of the used type as initial value, which is typically 0 for integer types and false for bool. You can use the set_value() method to set a different initial value.

Example

/// Create an instance of the debouncer.
let mut debouncer = timed_debouncer::Debouncer::new();

/// Number of ticks used to freeze the value when processing.
const DEBOUNCE_TICKS: u32 = 20;

// In real world, this is done somewhere in the main loop.
for tick in 0..50 {
    // Provide real values read from pins here.
    let input_value = if tick == 0 { 1 } else { 0 };

    let debounced_value = debouncer.update(input_value, tick, DEBOUNCE_TICKS);
    println!("{}: {:?} {:?}", tick, input_value, debounced_value);
}

Tests

Run cargo test for the unit tests.

License

Published under the MIT license. Any contribution to this project must be provided under the same license conditions.

Author: Oliver Rockstedt info@sourcebox.de