Struct hid_io_protocol::buffer::Buffer

pub struct Buffer<const Q: usize, const N: usize> { /* private fields */ }

HID-IO byte buffer This buffer is a queue of vecs with static allocation Each vec is fixed sized as HID-IO interface has a fixed transport payload (even if the actual size of the message is less). This buffer has no notion of packet size so it must store the full transport payload. In the minimal scenario a queue size of 1 is used.

Common HID-IO Vec capacities

• 7 bytes (USB 2.0 LS /w HID ID byte)
• 8 bytes (USB 2.0 LS)
• 63 bytes (USB 2.0 FS /w HID ID byte)
• 64 bytes (USB 2.0 FS)
• 1023 bytes (USB 2.0 HS /w HID ID byte)
• 1024 bytes (USB 2.0 HS)

The maximum queue size is 255

Implementations

impl<const Q: usize, const N: usize> Buffer<Q, N>

pub fn new() -> Buffer<Q, N>

Constructor for Buffer

Remarks

Initialize as blank This buffer has a limit of 65535 elements

pub fn peek(&self) -> Option<&Vec<u8, N>>

Checks the first item array Returns None if there are no items in the queue Does not dequeue

pub fn dequeue(&mut self) -> Option<Vec<u8, N>>

Dequeues and returns the first item array Returns None if there are no items in the queue

pub fn enqueue(&mut self, data: Vec<u8, N>) -> Result<(), Vec<u8, N>>

Enqueues Returns the array if there’s not enough space

pub fn clear(&mut self)

Clears the buffer Needed for some error conditions

pub fn capacity(&self) -> usize

Capacity of buffer

pub fn len(&self) -> usize

Number of elements stored in the buffer

pub fn is_empty(&self) -> bool

Buffer empty

pub fn is_full(&self) -> bool

Buffer full

Trait Implementations

impl<const Q: usize, const N: usize> Default for Buffer<Q, N>

fn default() -> Self

Returns the “default value” for a type.