Crate pamoja_can 

CAN bus framing for the pamoja SDK.

CAN is the bus that connects the moving parts of a machine: motor controllers, servos, battery management, and the engines, gensets, and farm equipment that speak J1939 on top of it. It is how a robot or a vehicle’s pieces talk to each other reliably over a short, noisy two-wire link, which is why it is the SDK’s path to actuators and to the diesel-and-hydraulic world of rural machinery.

This crate is the byte layer for that, with no controller and no allocation:

• CanId - a standard 11-bit or extended 29-bit identifier, always masked to width.
• Frame - a classic CAN 2.0 frame, a CAN-FD frame at the discrete CAN-FD lengths, or a remote frame, with len_to_dlc and dlc_to_len for the length encoding CAN-FD uses above eight bytes.
• J1939Id - the priority, parameter group, and addresses J1939 packs into a 29-bit identifier, decoded from one and composed back into one.

The controller hardware handles the wire itself (arbitration, bit timing, the frame CRC); this is the identifier and payload layer above it, the part an application actually reasons about. Driving a real controller arrives with the hardware-I/O layer.

Examples

use pamoja_can::{CanId, Frame, J1939Id};

// Build a classic frame for a motor controller.
let frame = Frame::new(CanId::standard(0x20A), &[0x01, 0xF4]).unwrap();
assert_eq!(frame.dlc(), 2);

// Decode an engine-speed broadcast from a J1939 genset.
let message = J1939Id::from_id(CanId::extended(0x0CF0_0400)).unwrap();
assert_eq!(message.pgn(), 61_444);
assert!(message.is_broadcast());

Modules

priority

The priorities J1939 conventionally assigns.

Structs

CanId

A CAN arbitration identifier.

Frame

A CAN frame: an identifier and its data.

J1939Id

The fields a J1939 message packs into its 29-bit identifier.

Signals

The eight data bytes of a J1939 frame.

Enums

CanError

What can go wrong building a CAN frame.

Constants

BROADCAST_ADDRESS

The destination address that means every node on the bus.

NOT_AVAILABLE

The byte a J1939 sender writes for a signal it is not reporting.

Functions

dlc_to_len

Maps a data-length code to the number of bytes it represents.

len_to_dlc

Maps a data length to the data-length code that represents it.