J1939

A Rust crate for the SAE J1939 automotive protocol.

Getting Started

Build a J1939 frame with PGN 'address claimed'.

let id = j1939::IdBuilder::from_pgn(j1939::PGN::AddressClaimed)
    .priority(3)
    .sa(0x11)
    .da(0xff)
    .build();

let frame = j1939::FrameBuilder::new(id)
    .copy_from_slice(&name.to_bytes()[..])
    .build();

Note that this just an example and not the actual 'address claimed' frame as specified by the SAE J1939 standard.

Some common PGNs have defined data structures. For example the Time/Date PGN is fully implemented.

let timedate = j1939::spn::TimeDate {
    year: 2024,
    month: 4,
    day: 20,
    hour: 10,
    minute: 1,
    second: 58,
    local_hour_offset: Some(0),
    local_minute_offset: Some(0),
};

let id = j1939::IdBuilder::from_pgn(j1939::PGN::TimeDate)
    .sa(0x28)
    .build();

let frame = j1939::FrameBuilder::new(id)
    .copy_from_slice(&timedate.to_pdu())
    .build();

Example

$ cargo run --example j1939decode 0x0CB34A29

This runs a J1939 ID decoder on the ID '0x0CB34A29'. Each of the J1939 aid properties can be accessed with this crate.

$ cargo run --example j1939decode 0x18FEE6EE#243412024029837D

This runs a J1939 decoder on the ID '0x18FEE6EE' and the data '243412024029837D' (which is PGN TimeDate).

When invoked without an argument and stdin is piped, the decoder reads one frame per line and prints a one-line summary. The last whitespace-separated token of each line is parsed as <id>#<data>, so candump -L output works directly.

$ candump -L can0 | cargo run --example j1939decode
0x18FEE6EE pri=6 PGN=TimeDate(0xFEE6) SA=0xEE GE=0xE6 DATA=243412024029837D
0x0CF00400 pri=3 PGN=ElectronicEngineController1(0xF004) SA=0x00 GE=0x04 DATA=0000000000000000

no_std

This crate supports no_std. By default the crate creates no_std targets which means you can use the J1939 crate on embedded systems that do not support dynamic allocation.

Contribution

All feedback welcome. Feel free to file bugs, requests for documentation and any other feedback to the [issue tracker][issues].

License

J1939 is distributed under the terms of GPL-3.0.

See LICENSE for details.