Struct WS2812Driver

pub struct WS2812Driver<const N: u8, const L: usize, PINS: Pins<N, L>>
where
    Instance<N>: Valid,
{ /* private fields */ }

A WS2812 Neopixel LED Strip driver based on the i.MX RT FlexIO module

Implementations

impl<const N: u8, const L: usize, PINS: Pins<N, L>> WS2812Driver<N, L, PINS>

where Instance<N>: Valid,

pub fn init(flexio: Instance<N>, pins: PINS) -> Result<Self, WS2812InitError>

Initializes the FlexIO driver.

IMPORTANT! Make sure that the clock input of the FlexIO instance is at 16MHz prior to calling this function.

Note that not all amounts of pins are always supported. The limiting factor is most likely the number of FlexIO timers; we need two timers plus an additional two per pin.

For example, if the FlexIO instance has 8 timers, it supports up to 3 pins.

pub fn take_interrupt_handler( &mut self, storage: &'static mut Option<InterruptHandlerData<N>>, ) -> InterruptHandler<N>

Take the interrupt handler callback from the driver.

Arguments

• storage - Static memory required by the function to work. See InterruptHandlerData for more information.

For correct functionality of write_dma() in waker-based async runtimes (like RTIC 2), it is required to invoke the returned InterruptHandler every time an interrupt of the given FlexIO peripheral happens.

pub fn write(&mut self, data: [&mut dyn PixelStreamRef; L])

Writes pixels to an LED strip.

If the strips are of different length, the shorter ones will be padded with 0 to match the longest strip.

For technical reasons, an additional [0, 0, 0] pixel will be added at the of the transmission.

pub async fn write_dma<F, R, const N2: usize, const P: usize>( &mut self, data: &PreprocessedPixels<N2, L, P>, dma: &mut Channel, dma_signal_id: u32, concurrent_action: F, ) -> Result<WriteDmaResult<R>, Error>

where F: Future<Output = R>,

Writes pixels to an LED strip.

In contrast to write(), this one performs the actual copy via DMA, whilst allowing for something else (like the next frame) to be computed concurrently.

Arguments

• data - Preprocessed pixel data to send to the LED strips
• dma - The dma channel that should be used to transmit the data
• dma_signal_id - The signal the FlexIO unit uses to communicate with the DMA. This is chip specific and must therefore be supplied by the user. The value can be found in the reference manual.
• concurrent_action - A function that will be executed while the pixels get transferred. Typically used to render the next frame, so it can be transmitted afterwards without a delay, to achieve the maximum possible framerate.

For technical reasons, an additional [0, 0, 0] pixel will be added at the of the transmission.

pub fn write_dma_blocking<F, R, const N2: usize, const P: usize>( &mut self, data: &PreprocessedPixels<N2, L, P>, dma: &mut Channel, dma_signal_id: u32, concurrent_action: F, ) -> Result<WriteDmaResult<R>, Error>

where F: FnOnce() -> R,

Same as write_dma(), but blocks until completion.

Do not use this function in an async context as it will busy-wait internally.