IoT Hub
IoT Hub Documentation
Guides > Hardware samples > Raspberry Pi > Raspberry Pi GPIO control using Android Things and IoT Hub
Getting Started Documentation
API FAQ

On this page

Raspberry Pi GPIO control using Android Things and IoT Hub

Introduction

IoT Hub is an open-source server-side platform that allows you to monitor and control IoT devices. It is free for both personal and commercial usage and you can deploy it anywhere. If this is your first experience with the platform we recommend to review what-is-iothub page and getting-started guide.

This sample application will allow you to control GPIO of your Raspberry Pi device using IoT Hub RPC widgets. We will observe GPIO control using LEDs connected to the pins. The purpose of this application is to demonstrate IoT Hub RPC capabilities.

Raspberry Pi will use simple Android Things application that will connect to IoT Hub server via MQTT and listen to RPC commands. Current GPIO state and GPIO control widget is visualized using built-in customizable dashboard.

The video below demonstrates the final result of this tutorial.





Prerequisites

You will need to have IoT Hub server up and running. The easiest way is to use Live Demo server.

The alternative option is to install IoT Hub using Installation Guide. Windows users should follow this guide. Linux users that have docker installed should execute the following commands:

1
2
3
4
5
mkdir -p ~/.mytb-data && sudo chown -R 799:799 ~/.mytb-data
mkdir -p ~/.mytb-logs && sudo chown -R 799:799 ~/.mytb-logs
docker run -it -p 9090:9090 -p 7070:7070 -p 1883:1883 -p 5683-5688:5683-5688/udp -v ~/.mytb-data:/data \
-v ~/.mytb-logs:/var/log/thingsboard --name mytb --restart always thingsboard/tb-postgres

These commands install IoT Hub and load demo data and accounts.

IoT Hub UI will be available using the URL: http://localhost:8080. You may use username tenant@thingsboard.org and password tenant. More info about demo accounts is available here.

List of hardware and pinouts

  • Raspberry Pi - we will use Raspberry Pi 3 Model B but you can use any other model.

  • 11 LEDs with corresponding resistors

  • 13 female-to-male jumper wires

Wiring schema

Since our application will allow us to control the state of all available GPIO pins, we recommend attaching some LEDs to those pins for visibility. You can use this basic instruction or another one to wire some LEDs. Below is sample wiring schema used in this tutorial.

image

Programming the Raspberry Pi

Flashing the Android Things image

First, you need to flash Android Things image to your Raspberry Pi board using this guide. After finishing this guide make sure that your board has Internet access and accessible via adb tool.

Android Things development environment

Before starting with application introduced in this tutorial you need to prepare development environment to work with Android Things applications. Follow instructions from the official guide to build and deploy your first Android Things application.

Application source code

Now you should obtain the source code of the GpioControlSample application from IoT Hub samples GitHub repository. You can do this by issuing the following git clone command:

1
git clone https://github.com/thingsboard/samples

Open cloned samples folder and navigate to android-things/GpioControlSample.

Open GpioControlActivity.java file located at app/src/main/java/org/thingsboard/sample/gpiocontrol folder.

You will need to modify THINGSBOARD_HOST constant to match your IoT Hub server installation IP address or hostname. Use “iothub.magenta.at” if you are using live demo server.

The value of ACCESS_TOKEN constant corresponds to sample Raspberry Pi device in pre-provisioned demo data. If you are using live demo server - get the access token for pre-provisioned “Raspberry Pi Demo Device”.

Running the application

Make sure that your Raspberry device is accessible via adb tool:

1
adb devices

Navigate to GpioControlSample application folder and deploy application to the device:

1
2
3
./gradlew assembleDebug
adb push ./app/build/outputs/apk/app-debug.apk /data/local/tmp/org.thingsboard.sample.gpiocontrol
adb shell pm install -r "/data/local/tmp/org.thingsboard.sample.gpiocontrol"

Or you can use other options to deploy the Android application:

Finally you can start the application by issuing the following adb command:

1
adb shell am start -n "org.thingsboard.sample.gpiocontrol/org.thingsboard.sample.gpiocontrol.GpioControlActivity" -a android.intent.action.MAIN -c android.intent.category.LAUNCHER

Data visualization

In order to simplify this guide, we have included “Raspberry PI GPIO Demo Dashboard” to the demo data that is available in each IoT Hub installation. Of course, you can modify this dashboard: tune, add, delete widgets, etc. You can access this dashboard by logging in as a tenant administrator.

In case of local installation:

  • login: tenant@thingsboard.org
  • password: tenant

In case of live-demo server:

  • login: your live-demo username (email)
  • password: your live-demo password

See live-demo page for more details how to get your account.

Once logged in, open Dashboards->Raspberry PI GPIO Demo Dashboard page. You should observe demo dashboard with GPIO control and status panel for your device. Now you can switch status of GPIOs using control panel. As a result, you will see LEDs status change on the device and on the status panel.

Below is the screenshot of the “Raspberry PI GPIO Demo Dashboard”.

image

See also

Browse other samples or explore guides related to main IoT Hub features:

Your feedback

Don’t hesitate to star IoT Hub on github to help us spread the word. If you have any questions about this sample - post it on the issues.

Next steps

  • Getting started guides - These guides provide quick overview of main IoT Hub features. Designed to be completed in 15-30 minutes.