VL53L1X library for Rust on Linux ![Latest Version] ![Documentation]

A Rust library for the VL53L1x Time-of-Flight sensor. Also, a shared library for using the VL53L1X on Linux without Rust.

Usage

``` extern crate vl53l1x;

pub fn main() { let mut vl = vl53l1x::Vl53l1x::new(1).unwrap(); vl.init().unwrap(); vl.startranging(vl53l1x::DistanceMode::Long).unwrap(); loop { println!("Sample: {:?}", vl.readsample()); } } ```

See examples/scan.rs for a more thorough example.

Features

• Set distance mode (short, mid, long).
• Change i2c address of device.
• Get/set region of interest to adjust field of view.
• Makefile can be used to generate static or dynamic library without Rust.
• Verified that the ST library and additions made do not leak memory using valgrind.

Approach

This compiles a C library that is then statically linked to your Rust program via the crate. The C library is based on the official ST C API. Their headers conveniently abstract away platform-specific i2c implementations into vl53l1_platform.c which I've used to implement the Linux i2c interface (linux/i2c-dev.h).

This approach differs from VL53L1XArduinoLibrary which reimplements the official library with mostly replays of i2c data stream captures. That approach results in a smaller memory footprint (good for Arduinos), but is less featured and more fragile. e.g. I've observed discrepancies in distance measurements between their library and the official. Their painstaking work is a direct result of ST not releasing an official i2c register datasheet for the device.

This approach is similar to vl53l1x-python. However, that relies on Python providing an i2c function. This library implements the i2c adapter in C and is fully self-contained, which makes it ideal for being published as a shared library libvl53l1x.so.

Cross Compilation

Specify a custom C-compiler using the VL53L1X_CC env arg. For example:

VL53L1X_CC=arm-linux-gnueabihf-gcc cargo build

Platform

This library has only been tested on the Raspberry Pi 3 B+.

NOTE: Dynamically-Linked Library

At some point, the dynamically-linked library will be published in its own repo without Rust. For now, you can checkout the repo and run the following from the root of the repository:

make libvl53l1x_api.so

The lib will be in the build directory.

Todo

• [ ] Publish libvl53l1x.so for non-Rust, Linux usage.
• [ ] Get/set timing budget.

Resources

• Datasheet

Licenses

ST's library is dual licensed with BSD and their own proprietary one. The rest is licensed under MIT.