leachj / vl6180_pi

Raspberry Pi library for the VL6180 i2c distance sensor

Synopsis

This library provides convenient access to distance measurements from the VL6180 i2c time of flight distance sensor on the raspberry pi. The sensor board I have been using is from SparkFun https://www.sparkfun.com/products/12785

Although it is designed for the Pi it is likely to work with most linux systems.

Code Examples

The library is very simple to use, here is the basic code for getting distance measurements

#include <vl6180_pi/vl6180_pi.h>

...

vl6180 handle = vl6180_initialise(1);

int distance = get_distance(handle);

The integer passed into initialise is the i2c device number /dev/i2c-n

The distance returned will be in mm

#include <vl6180_pi/vl6180_pi.h>

...

vl6180 handle = vl6180_initialise(1);

float ambient_light = get_ambient_light(handle, GAIN);

The ambient light returned will be in lx.

GAIN - predefined value from vl6180_pi.h. For factory calibrated sensor GAIN_1 is appropriate.

Motivation

Whilst there as already an existing Arduino library for the sensor there was nothing to allow it to work with the Pi. This project solves that.

Installation

To install the library download the code and then run

make
sudo make install

If you do not have the i2c device on your pi you need to enable i2c. This can be done by following the instructions here: https://learn.adafruit.com/adafruits-raspberry-pi-lesson-4-gpio-setup/configuring-i2c

You may also need to install i2c-tools libi2c-dev

sudo apt-get install i2c-tools libi2c-dev

Tests

To test the basic functionality download the code and then run

make check

Contributors

Contributions are welcome. This only implements a very simple usage of the VL6180, it has many other functions which could be added to this library.

License

This software is made available under the MIT license

vl6180_pi's Issues

Initial registers not set under some circumstances

In the vl6180 vl6180_initialise function if register 0x016 doesn't return a 1 the recommended registers don't get set. I have two of these sensors and neither ever seems to return a 1. Oddly enough it seems measure distance just fine without them getting set.

Missing -fPIC

Some newer compilers complain about missing -fPIC in the source file compile. Also, the typedef is outside of the C++ check, so if you build this from C++, it won't work. Patch attached as a .txt file.

build-fixes.txt