#no-std #device #driver #toolkit

no-std device-driver

A toolkit to write better device drivers, faster

7 unstable releases

0.4.1 Dec 13, 2022
0.4.0 Dec 13, 2022
0.3.1 Dec 22, 2021
0.3.0 May 2, 2021
0.1.0 Sep 28, 2020

#89 in Hardware support

Download history 1/week @ 2023-06-09 33/week @ 2023-06-16 19/week @ 2023-06-23 22/week @ 2023-06-30 30/week @ 2023-07-07 9/week @ 2023-07-14 15/week @ 2023-07-21 9/week @ 2023-07-28 10/week @ 2023-08-04 9/week @ 2023-08-11 18/week @ 2023-08-18 13/week @ 2023-08-25 13/week @ 2023-09-01 48/week @ 2023-09-08 13/week @ 2023-09-15 6/week @ 2023-09-22

82 downloads per month
Used in 2 crates


1.5K SLoC

Device driver toolkit #![no_std] crates.io Documentation

A toolkit to write better device drivers, faster.

See this example to see how it works. There's also this OPL2 device driver that is used as reference register implementation for this crate.

You can now also generate an async interface. See this example. This is only supported on a recent nightly as of writing (13-12-22).

Feedback and feature requests are appreciated! Just open an issue on github.


// Create our low level device. This holds all the hardware communication definitions
    /// Our test device
    MyDevice {
        // The types of errors our low level error enum must contain
        errors: [InterfaceError],
        hardware_interface_requirements: { RegisterInterface },
        hardware_interface_capabilities: {
            fn reset(&mut self) -> Result<(), InterfaceError>;

// Create a register set for the device
    /// The global register set that uses a u8 as register address
    MyDevice.registers<u8> = {
        /// The identification register (which is RO (Read Only))
        #[generate(Debug)] // We want a fancy debug impl
        id(RO, 0, 3) = {
            /// The manufacturer code
            manufacturer: u16 as Manufacturer = RO 0..16, // Cast the raw int to an enum
            /// The version of the chip
            version: u8 = RO 16..20,
            /// The edition of the chip
            edition: u8 = RO 20..24,
        // ....
        // ....
        // ....

/// Does some random register things to showcase how everything works
fn run<SPI, CS, RESET>(
    device: &mut MyDevice<ChipInterface<SPI, CS, RESET>>,
) -> Result<(), LowLevelError>
    SPI: Transfer<u8> + Write<u8>,
    CS: OutputPin,
    RESET: OutputPin,
    // We read the manufacturer
    let id = device.registers().id().read()?;

    // Print the id. It is marked with `#[generate(Debug)]`,
    // so it should only show all fields
    println!("{:?}", id);

    // Enable output on pin 0
        .write(|w| w.output_0(Bit::Set).mask_0(Bit::Set))?;

    // Disable the irq status bit
        .modify(|_, w| w.irq_status(Bit::Cleared))?;



Licensed under either of

at your option.


Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.


  • Better error handling. (Suggestions?)
  • Adding memory devices support.
  • Allow user to specify default register values.
  • Create tools for helping create high level layers.
  • Allow register specification based on files? (Work together with bitinfo?)


This crate is far from stable. But if it works for you, then I see no reason why you couldn't use it already. Only updating to a new version may break stuff and proper Semver will be used.


0.4.1 (13-12-22)

  • Accidentally left the async flag on by default for 0.4.0 which caused it not to compile on stable.

0.4.0 (13-12-22) (yanked)

  • Added async support for the register interfaces. Use the async feature flag to activate it. When you do, you will have access to the ll::register_async module that will generate async code for you.
  • Updated dependencies (mainly bitvec to 1.0, which makes this release a technically breaking change)

0.3.1 (22-12-21)

  • Added docs to low level error (#14)

0.3.0 (02-05-21)

  • Added better Debug impls to all register R that prints the raw value in hex. There's now also the option (#[generate(Debug)]) to get an even better Debug impl that also prints out all the fields, but does require all fields to impl Debug themselves. See (#10) to see how it works.

0.2.0 (19-04-21)

  • All user interaction with a 'W' is now through &mut instead of directly to support more kinds of code structuring (#7)


~23K SLoC