can_hal/
bus.rs

1use crate::error::CanError;
2
3/// The error state of a CAN bus controller.
4#[derive(Debug, Clone, Copy, PartialEq, Eq)]
5pub enum BusState {
6    /// Normal operation. Error counters are below 128.
7    ErrorActive,
8    /// Error counters have reached the warning threshold (128–255).
9    /// The controller can still communicate but may be experiencing issues.
10    ErrorPassive,
11    /// The controller has gone off-bus due to excessive errors (counter > 255).
12    /// No frames can be sent or received until recovery.
13    BusOff,
14}
15
16/// Transmit and receive error counters from the CAN controller.
17#[derive(Debug, Clone, Copy, PartialEq, Eq)]
18pub struct ErrorCounters {
19    pub transmit: u8,
20    pub receive: u8,
21}
22
23/// Query the health and error state of a CAN bus controller.
24///
25/// Not all backends support this - it is an optional trait.
26pub trait BusStatus {
27    type Error: CanError;
28
29    /// Returns the current bus state of the controller.
30    fn bus_state(&self) -> Result<BusState, Self::Error>;
31
32    /// Returns the current transmit and receive error counters.
33    fn error_counters(&self) -> Result<ErrorCounters, Self::Error>;
34}
can_hal/bus.rs

can_hal/
bus.rs
