blinksy 0.11.0

no-std, no-alloc LED control library designed for 1D, 2D, and 3D layouts
Documentation 
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use fugit::NanosDurationU32 as Nanoseconds;

use crate::{
    color::{LedChannels, RgbChannels},
    driver::ClocklessLed,
};

/// # WS2812 (NeoPixel) LEDs
///
/// This type describes the WS2812 (NeoPixel) LEDs, which are widely used due to their
/// simplicity and low cost.
///
/// # Driver
///
/// - [`ClocklessDriver`](crate::driver::ClocklessDriver)
///
/// ## Key Features
///
/// - Single-wire [clockless protocol](crate::driver::clockless) (data only, no clock)
/// - 24-bit color (8 bits per channel, 3 channels)
/// - Fixed update rate: 30μs per pixel
pub struct Ws2812;

impl Ws2812 {
    /// A compile-time function to get a `FRAME_BUFFER_SIZE`, given a `PIXEL_COUNT`.
    ///
    /// ```rust,ignore
    /// layout1d!(Layout, 60);
    ///
    /// let mut control = ControlBuilder::new_1d()
    ///   // ...
    ///   .with_frame_buffer_size::<{ Ws2812::frame_buffer_size(Layout::PIXEL_COUNT) }>()
    ///   .build();
    /// ```
    pub const fn frame_buffer_size(pixel_count: usize) -> usize {
        super::clockless_frame_buffer_size::<Self>(pixel_count)
    }
}

/// ## Protocol Details
///
/// The WS2812 protocol uses precise timing of pulses on a single data line:
///
/// - A '0' bit is represented by a short high pulse (~400ns) followed by a long low pulse (~850ns)
/// - A '1' bit is represented by a long high pulse (~800ns) followed by a short low pulse (~450ns)
/// - After sending all bits, a reset pulse of at least 50µs is required
///
/// (References: [Datasheet](https://cdn-shop.adafruit.com/datasheets/WS2812B.pdf))
///
/// Each LED receives 24 bits (RGB) and then passes subsequent data to the next LED in the chain.
///
impl ClocklessLed for Ws2812 {
    type Word = u8;

    /// Duration of high signal for '0' bit (~400ns)
    const T_0H: Nanoseconds = Nanoseconds::nanos(400);

    /// Duration of low signal for '0' bit (~850ns)
    const T_0L: Nanoseconds = Nanoseconds::nanos(850);

    /// Duration of high signal for '1' bit (~800ns)
    const T_1H: Nanoseconds = Nanoseconds::nanos(800);

    /// Duration of low signal for '1' bit (~450ns)
    const T_1L: Nanoseconds = Nanoseconds::nanos(450);

    /// Reset period (>50µs) - signals the end of a data stream
    const T_RESET: Nanoseconds = Nanoseconds::micros(50);

    /// LED channel specification - WS2812 uses GRB ordering
    const LED_CHANNELS: LedChannels = LedChannels::Rgb(RgbChannels::GRB);
}