Struct DmaRxTxBuf

pub struct DmaRxTxBuf { /* private fields */ }

Available on crate feature unstable only.

DMA transmit and receive buffer.

This is a (single) contiguous buffer linked together by two sets of DMA descriptors of length 4092 each. It can be used for simultaneously transmitting to and receiving from a peripheral’s FIFO. These are typically full-duplex transfers.

Implementations

impl DmaRxTxBuf

pub fn new( rx_descriptors: &'static mut [DmaDescriptor], tx_descriptors: &'static mut [DmaDescriptor], buffer: &'static mut [u8], ) -> Result<Self, DmaBufError>

Creates a new DmaRxTxBuf from some descriptors and a buffer.

There must be enough descriptors for the provided buffer. Each descriptor can handle 4092 bytes worth of buffer.

Both the descriptors and buffer must be in DMA-capable memory. Only DRAM is supported.

pub fn set_burst_config( &mut self, burst: BurstConfig, ) -> Result<(), DmaBufError>

Configures the DMA to use burst transfers to access this buffer.

pub fn split( self, ) -> (&'static mut [DmaDescriptor], &'static mut [DmaDescriptor], &'static mut [u8])

Consume the buf, returning the rx descriptors, tx descriptors and buffer.

pub fn capacity(&self) -> usize

Return the size of the underlying buffer.

pub fn len(&self) -> usize

Return the number of bytes that would be transmitted by this buf.

pub fn as_slice(&self) -> &[u8]

Returns the entire buf as a slice than can be read.

pub fn as_mut_slice(&mut self) -> &mut [u8]

Returns the entire buf as a slice than can be written.

pub fn set_length(&mut self, len: usize)

Reset the descriptors to only transmit/receive len amount of bytes with this buf.

len must be less than or equal to the buffer size.

Trait Implementations

impl Debug for DmaRxTxBuf

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl DmaRxBuffer for DmaRxTxBuf

type View = BufView<DmaRxTxBuf>

A type providing operations that are safe to perform on the buffer whilst the DMA is actively using it.

fn prepare(&mut self) -> Preparation

Prepares the buffer for an imminent transfer and returns information required to use this buffer.

fn into_view(self) -> BufView<DmaRxTxBuf>

This is called before the DMA starts using the buffer.

fn from_view(view: Self::View) -> Self

This is called after the DMA is done using the buffer.

impl DmaTxBuffer for DmaRxTxBuf

type View = BufView<DmaRxTxBuf>

A type providing operations that are safe to perform on the buffer whilst the DMA is actively using it.

fn prepare(&mut self) -> Preparation

Prepares the buffer for an imminent transfer and returns information required to use this buffer.

fn into_view(self) -> BufView<DmaRxTxBuf>

This is called before the DMA starts using the buffer.

fn from_view(view: Self::View) -> Self

This is called after the DMA is done using the buffer.

impl Format for DmaRxTxBuf

where DescriptorSet<'static>: Format, &'static mut [u8]: Format, BurstConfig: Format,

fn format(&self, f: Formatter<'_>)

Writes the defmt representation of self to fmt.