Struct DmaRxBuf

pub struct DmaRxBuf { /* private fields */ }

Available on crate feature unstable only.

DMA receive buffer

This is a contiguous buffer linked together by DMA descriptors of length 4092. It can only be used for receiving data from a peripheral’s FIFO. See DmaTxBuf for transmitting data.

Implementations

impl DmaRxBuf

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

Creates a new DmaRxBuf 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 new_with_config( descriptors: &'static mut [DmaDescriptor], buffer: &'static mut [u8], config: impl Into<BurstConfig>, ) -> Result<Self, DmaBufError>

Creates a new DmaRxBuf from some descriptors and a buffer.

There must be enough descriptors for the provided buffer. Depending on alignment requirements, each descriptor can handle at most 4092 bytes worth of buffer.

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

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 [u8])

Consume the buf, returning the descriptors and buffer.

pub fn capacity(&self) -> usize

Returns the size of the underlying buffer

pub fn len(&self) -> usize

Returns the maximum number of bytes that this buf has been configured to receive.

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

Reset the descriptors to only receive len amount of bytes into this buf.

The number of bytes in data must be less than or equal to the buffer size.

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

Returns the entire underlying buffer as a slice than can be read.

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

Returns the entire underlying buffer as a slice than can be written.

pub fn number_of_received_bytes(&self) -> usize

Return the number of bytes that was received by this buf.

pub fn read_received_data(&self, buf: &mut [u8]) -> usize

Reads the received data into the provided buf.

If buf.len() is less than the amount of received data then only the first buf.len() bytes of received data is written into buf.

Returns the number of bytes in written to buf.

pub fn received_data(&self) -> impl Iterator<Item = &[u8]>

Returns the received data as an iterator of slices.

Trait Implementations

impl Debug for DmaRxBuf

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

Formats the value using the given formatter.

impl DmaRxBuffer for DmaRxBuf

type View = BufView<DmaRxBuf>

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<DmaRxBuf>

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.