RPPAL - Raspberry Pi Peripheral Access Library

RPPAL is a Rust library that provides access to the Raspberry Pi's GPIO peripheral. Support for additional peripherals will be added in future updates. The library is compatible with the Raspberry Pi A, A+, B, B+, 2B, 3B, 3B+, Compute, Compute 3, Zero and Zero W.

Backwards compatibility for minor revisions isn't guaranteed until the library reaches v1.0.0.

Supported peripherals

GPIO

For performance reasons, the library accesses the GPIO peripheral mainly through either /dev/gpiomem or /dev/mem. GPIO pin interrupts are controlled using the sysfs interface.

Features:

Get/set pin mode.
Read/write pin level.
Set built-in pull-up/pull-down resistors.
Set synchronous and asynchronous interrupts.

Documentation

Documentation for the latest release can be found at docs.golemparts.com/rppal. Documentation for earlier releases is stored at docs.rs/rppal.

Usage

Add a dependency for rppal to your Cargo.toml.

[dependencies]
rppal = "0.5"

Link and import rppal from your crate root.

extern crate rppal;

Call Gpio::new() to create a new Gpio instance with the default settings. In production code, you'll want to parse the result rather than unwrap it.

use rppal::gpio::Gpio;

let mut gpio = Gpio::new().unwrap();

Example

extern crate rppal;

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

use rppal::gpio::{Gpio, Mode, Level};
use rppal::system::DeviceInfo;

// The GPIO module uses BCM pin numbering. BCM 18 equates to physical pin 12.
const GPIO_LED: u8 = 18;

fn main() {
    let device_info = DeviceInfo::new().unwrap();
    println!("Model: {} (SoC: {})", device_info.model(), device_info.soc());

    let mut gpio = Gpio::new().unwrap();
    gpio.set_mode(GPIO_LED, Mode::Output);

    // Blink an LED attached to the pin on and off
    gpio.write(GPIO_LED, Level::High);
    thread::sleep(Duration::from_millis(500));
    gpio.write(GPIO_LED, Level::Low);
}

Caution

Always be careful when working with the Raspberry Pi's peripherals, especially if you attach any external components to the GPIO pins. Improper use can lead to permanent damage.

Cross compilation

If you're not working directly on a Raspberry Pi, you'll likely need to cross compile your code for the appropriate ARM architecture. Check out this guide for more information, or try the cross project for "zero setup" cross compilation.

rppal 0.5.0