rpi_gpio.dart
rpi_gpio is a Dart package for accessing the Raspberry Pi GPIO pins.
Overview
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The Gpio library provides the API for accessing the various General Purpose I/O pins on the Raspberry Pi.
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RpiGpio provides the implementation for the Gpio API derived from the WiringPi library.
Setup
RpiGpio accesses the GPIO pins using a native library written in C. For security reasons, authors cannot publish binary content to pub.dartlang.org, so there are some extra steps necessary to compile the native library on the RPi before this package can be used. These two steps must be performed when you install and each time you upgrade the rpi_gpio package.
- Activate the rpi_gpio package using the pub global command.
pub global activate rpi_gpio
- From your application directory (the application that references the rpi_gpio package) run the following command to build the native library
pub global run rpi_gpio:build_native
pub global activate makes the Dart scripts in the rpi_gpio/bin directory runnable from the command line. pub global run rpi_gpio:build_native runs the rpi_gpio/bin/build_native.dart program which in turn calls the build_native script to compile the native librpi_gpio_ext.so library for the rpi_gpio package.
Alternately, if you checked out rpi_gpio into it's own directory
and are modifying it or referencing it from a different pubspec.yaml using a relative path,
then you can skip #1 and #2 above, and just run
cd /to/your/local/rpi_gpio
dart bin/build_native.dart
Example
The example launches the example app to demonstrate:
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Blinking an LED along with software based PWM on a second LED.
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Responding to a button press by turning on an LED.
The example is structured such that the example test can inject a mock gpio to facilitate testing and allow test execution on platforms other than the Raspberry Pi.