i2cdev 0.3.2

Provides API for safe access to Linux i2c device interface. https://www.kernel.org/doc/Documentation/i2c/dev-interface

Rust I2cdev

Build Status Version License

Documentation

The Rust i2cdev crate seeks to provide full access to the Linux i2cdev driver interface in Rust without the need to wrap any C code or directly make low-level system calls. The documentation for the i2cdev interace can be found at https://www.kernel.org/doc/Documentation/i2c/dev-interface and in the lm-sensors projects.

Example/API

The source includes an example of using the library to talk to a Wii Nunchuck (which has an i2c interface). Go View the Example.

Here's a real quick example showing the guts of how you create device and start talking to it... This device only requires basic functions (read/write) which are done via the Read/Write traits (if you actually want to use the Wii Nunchuck you should use i2cdev::sensors::nunchuck::Nunchuck:

extern crate i2cdev;

use std::thread;
use std::time::Duration;

use i2cdev::core::*;
use i2cdev::linux::{LinuxI2CDevice, LinuxI2CError};

const NUNCHUCK_SLAVE_ADDR: u16 = 0x52;

// real code should probably not use unwrap()
fn i2cfun() -> Result<(), LinuxI2CError> {
    let mut dev = try!(LinuxI2CDevice::new("/dev/i2c-1", NUNCHUCK_SLAVE_ADDR));

    // init sequence
    try!(dev.smbus_write_byte_data(0xF0, 0x55));
    try!(dev.smbus_write_byte_data(0xFB, 0x00));
    thread::sleep(Duration::from_millis(100));

    loop {
        let mut buf: [u8; 6] = [0; 6];
        dev.smbus_write_byte(0x00).unwrap();
        thread::sleep(Duration::from_millis(10));
        dev.read(&mut buf).unwrap();
        println!("Reading: {:?}", buf);
    }
}

In addition to the Read/Write traits, the following methods are available via the I2CDevice trait.

Features

The following features are implemented and planned for the library:

  • Implement the Read trait
  • Implement the Write trait
  • Implement SMBus Methods
  • Add Tests/Example for SMBus Methods
  • Add sensor library for handy sensors (and examples)
  • Add higher-level APIs/Macros for simplifying access to devices with large register sets
  • Add Support for Non-SMBus ioctl methods
  • Add examples for non-smbus ioctl methods
  • Unit Testing

Cross Compiling

Most likely, the machine you are running on is not your development machine (although it could be). In those cases, you will need to cross-compile. See https://github.com/japaric/rust-cross for pointers.

License

Copyright (c) 2015, Paul Osborne <ospbau@gmail.com>

Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
http://www.apache.org/license/LICENSE-2.0> or the MIT license
<LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
option.  This file may not be copied, modified, or distributed
except according to those terms.