Home Assistant is an open source home automation software which tracks the state of the smart-devices in your home so you don't have to. It easily integrates with most smart-devices (Google Cast, Philips Hue, Nest, Sonos, etc) and even interfaces with smart-assistants like Alexa or Google Assistant. 

Adafruit sells a lot of different types of sensors. Following this guide will let you quickly connect them to Home Assistant using an Adafruit Feather.

We're going to set up an Adafruit Feather ESP8266 with a BME280 sensor to create a temperature, pressure, and humidity logging node. Then we'll install, set up, and configure Home Assistant on a Raspberry Pi.

We'll configure the Feather to broadcast its sensor data to both Home Assistant and Adafruit IO using ESPHomeYAML.

While Home Assistant is fantastic at displaying data in real-time, you might want to manipulate and log the data. We'll be using Adafruit IO to perform real-time and long-term logging for visualization of data, and export the data from sensor feeds.

Parts

Note: While you can run HassOS on a Pi Zero W, we do not suggest using one with this guide. The process of flashing firmware from a Pi Zero W is difficult. Compiling and uploading the Feather's firmware from a Pi Zero W takes significantly more time than a Pi 3B+. 

Materials

You'll need the items below for this project. If you do not have them already, grab them from the Adafruit Store:

You may also want to connect a LiPo battery to the JST connector on the Feather Huzzah for wire-free logging. This one is ideal for Feathers:

If you do not already have an Adafruit IO account set up, head over to io.adafruit.com to link your Adafruit.com account to Adafruit IO.

Navigate to the feeds page on Adafruit IO. Then click Actions -> Create New Feed, and name this feed humidity. 

• If you do not already know how to create a feed, head over to Adafruit IO Basics: Feeds.

Then, create a temperature and pressure feed for the BME280's temperature and pressure sensors.

Also, create an additional feed named status. When your Feather turns on or off, it'll broadcast its connection status to this feed.

We're also going to need our Adafruit IO username and secret API key.

Navigate to your profile and click the View AIO Key button to retrieve them. Write them down in a safe place, we'll need them for later.

With Adafruit IO set up, we'll move on to installing HassOS

We'll be installing Home Assistant locally on a Raspberry Pi using Hass.io, an All-in-One image which turns your Pi into a home assistant hub.

The process of installing and configuring HassOS takes a while. Luckily, you only have to do it once.

First, download the latest Hass.io image for your device from the home assistant downloads page.

Then, unzip the .img.gz file. You should now have a .img file.

Burn the OS image to a fresh SD card (Home Assistant's website suggests a 32GB SD card or larger). 

• If you do not know how to install an OS onto a SD card for the Raspberry Pi, follow this page and come back when you're done.

WiFi Configuration

If you want to connect your Pi over WiFi, you'll need to configure Hass first. HassOS uses NetworkManager to control the host network and defaults to ethernet. 

HassOS uses a USB Drive to load configuration files like WiFi onto the Pi. The capacity of the stick does not matter - we'll be adding one file to the drive. 

Once reformatted, make a folder on the drive named network. 

Then, create a new file called my-network inside the network folder we just created.

Copy and paste the following into the file:

[connection]
id=hassos-network
uuid=72111c67-4a5d-4d5c-925e-f8ee26efb3c3
type=802-11-wireless

[802-11-wireless]
mode=infrastructure
ssid=MY_SSID
# Uncomment below if your SSID is not broadcasted
#hidden=true

[802-11-wireless-security]
auth-alg=open
key-mgmt=wpa-psk
psk=MY_WLAN_SECRET_KEY

[ipv4]
method=auto

[ipv6]
addr-gen-mode=stable-privacy
method=auto

[connection]
id=hassos-network
uuid=72111c67-4a5d-4d5c-925e-f8ee26efb3c3
type=802-11-wireless

[802-11-wireless]
mode=infrastructure
ssid=MY_SSID
# Uncomment below if your SSID is not broadcasted
#hidden=true

[802-11-wireless-security]
auth-alg=open
key-mgmt=wpa-psk
psk=MY_WLAN_SECRET_KEY

[ipv4]
method=auto

[ipv6]
addr-gen-mode=stable-privacy
method=auto

In the configuration, change ssid to your network's ssid and change psk to the password of your network.

Save the file to the USB drive and eject the drive from your computer. Safely eject the SD card from your computer at this time, too.

HassOS Setup

After setup, you'll be directed to the Home Assistant login page. Remove the USB drive from the Raspberry Pi.

Next, we'll configure Home Assistant to be used with the Feather.

HassOS requires a bit of configuration before it's ready to be used with the Feather.

Home Assistant uses a YAML file named configuration.yaml for each component used by Home Assistant. Previously, editing this file involved setting up SSH or SAMBA sharing on the Raspberry Pi.

We're going to use an add-on which lets us edit this file right from our browser.

Configuring Add-ons

While the Configurator and esphomeyaml add-ons are installed, they need some configuration. We'll start with the Configurator add on. 

After you've configured both the IP and the password, click Start. A button to Open Web UI will appear when the Configurator successfully starts.

In the Configurator editor, make sure the file you are editing is /config/configuration.yaml.

Then, add an entry in the configuration.yaml file to enable MQTT Discovery:

# MQTT Discovery
mqtt:
  discovery: true
  discovery_prefix: homeassistant

# MQTT Discovery
mqtt:
  discovery: true
  discovery_prefix: homeassistant

and Click Save.

Since we changed the configuration.yaml, we'll want to validate the file to make sure nothing goes wrong when we restart Home Assistant. 

Click Check Config

After checking the configuration, we'll want to restart the server. We don't need to SSH into the Raspberry Pi and issue a restart command - Home Assistant lets us do this from within the Configuration page.

From the Configuration page, scroll down to Server Management and click Restart.

If you refresh the page, you'll encounter a Connection lost. Reconnecting... message. Since we restarted the server, it'll take a few minutes to get itself back online.

After a few minutes, refresh the page.

Once we're connected back to HassOS, we'll proceed to configuring the Feather with ESPHomeYAML.

Flashing firmware with Raspberry Pi

ESPHomeYAML is a tool which creates custom firmware for ESP8266/ESP32 boards and sensors from a Yet-Another-Markup-Language (YAML) file. We're going to be using the official Home Assistant add-on for ESPHomeYAML to help generate firmware for the Feather. Then, we'll upload the firmware directly to the board.

Note: If you are using any single-board computer slower than a Pi 3, such as a Pi Zero, expect to wait a significant amount of time while the firmware compiles and uploads to the Feather Huzzah. 

Plug the Feather into a USB Cable, and then into one of the Raspberry Pi 3B+'s USB ports.

From the ESPHomeYAML dashboard, click the Plus Icon to launch the ESPHome Setup Wizard. 

After the setup wizard completes, a new node will appear on the ESPHome dashboard. We're not ready to upload the settings yet.

Click Edit

The feather_bme280.yaml file below is based off of the template provided in Boris Hajduk's guide `Using adafruit.io MQTT with esphomeyaml`. 

Copy and paste the file below into the ESPHome Dashboard file editor:

# ESPHomeYAML Configuration
# for Home Assistant and Adafruit IO

substitutions:
  device_name: feather_bme280
  io_username: YOUR_ADAFRUIT_IO_USERNAME
  io_key: YOUR_ADAFRUIT_IO_KEY
  update_interval: 30s

esphomeyaml:
  name: ${device_name}
  platform: ESP8266
  board: huzzah

# WiFi Configuration
wifi:
  ssid: 'YOUR_SSID'
  password: 'YOUR_SSID_PASSWORD'
  # Uncomment this for Static IP Configuration
  #manual_ip:
    # Set this to the IP of the ESP
    #static_ip: 10.0.0.0
    # Set this to the IP address of the router. Often ends with .1
    #gateway: 10.0.0.1
    # The subnet of the network. 255.255.255.0 works for most home networks.
    #subnet: 255.255.255.0

# Adafruit IO MQTT Setup
mqtt:
  broker: 'io.adafruit.com'
  username: ${io_username}
  password: ${io_key}
  topic_prefix: '${io_username}/feeds'
  birth_message:
    topic: ${io_username}/feeds/status
    payload: Online
  will_message:
    topic: ${io_username}/feeds/status
    payload: Offline
  log_topic:

# Enable Home Assistant API
api:

# Enable OTA Access
ota:

# Enable verbose logging over serial
logger:

# Create BME Sensor on I2C
i2c:
  sda: SDA
  scl: SCL
  scan: False
binary_sensor:
    - platform: status
      name: "BME280 Status"
      id: status
      internal: True
sensor:
  - platform: bme280
    address: 0x77
    temperature:
      name: "BME280 Temperature"
      id: temperature
      state_topic: ${io_username}/feeds/temperature
      discovery: False
      filters: []
    pressure:
      name: "BME280 Pressure"
      id: pressure
      state_topic: ${io_username}/feeds/pressure
      discovery: False
      filters: []
    humidity:
      name: "BME280 Humidity"
      id: humidity
      state_topic: ${io_username}/feeds/humidity
      discovery: False
      filters: []
    update_interval: ${update_interval}

# ESPHomeYAML Configuration
# for Home Assistant and Adafruit IO

substitutions:
  device_name: feather_bme280
  io_username: YOUR_ADAFRUIT_IO_USERNAME
  io_key: YOUR_ADAFRUIT_IO_KEY
  update_interval: 30s

esphomeyaml:
  name: ${device_name}
  platform: ESP8266
  board: huzzah

# WiFi Configuration
wifi:
  ssid: 'YOUR_SSID'
  password: 'YOUR_SSID_PASSWORD'
  # Uncomment this for Static IP Configuration
  #manual_ip:
    # Set this to the IP of the ESP
    #static_ip: 10.0.0.0
    # Set this to the IP address of the router. Often ends with .1
    #gateway: 10.0.0.1
    # The subnet of the network. 255.255.255.0 works for most home networks.
    #subnet: 255.255.255.0

# Adafruit IO MQTT Setup
mqtt:
  broker: 'io.adafruit.com'
  username: ${io_username}
  password: ${io_key}
  topic_prefix: '${io_username}/feeds'
  birth_message:
    topic: ${io_username}/feeds/status
    payload: Online
  will_message:
    topic: ${io_username}/feeds/status
    payload: Offline
  log_topic:

# Enable Home Assistant API
api:

# Enable OTA Access
ota:

# Enable verbose logging over serial
logger:

# Create BME Sensor on I2C
i2c:
  sda: SDA
  scl: SCL
  scan: False
binary_sensor:
    - platform: status
      name: "BME280 Status"
      id: status
      internal: True
sensor:
  - platform: bme280
    address: 0x77
    temperature:
      name: "BME280 Temperature"
      id: temperature
      state_topic: ${io_username}/feeds/temperature
      discovery: False
      filters: []
    pressure:
      name: "BME280 Pressure"
      id: pressure
      state_topic: ${io_username}/feeds/pressure
      discovery: False
      filters: []
    humidity:
      name: "BME280 Humidity"
      id: humidity
      state_topic: ${io_username}/feeds/humidity
      discovery: False
      filters: []
    update_interval: ${update_interval}

Before uploading the file, we'll need to make the following adjustments to the YAML file under substitutions:

• Change device_name to reflect the name of the device you created in the ESPHome Wizard.
• Set io_username to your Adafruit IO Username
• Set io_key to your Adafruit IO Key
• Change update_interval to the frequency (in seconds) which you'd like the feather to read the sensor and send its data to Home Assistant and Adafruit IO.

We'll also need to configure the WiFi network:

• Set ssid to your network's ssid
• Set password to your network's password

After configuration of the YAML file is complete, click save.

Finally, we'll move onto uploading the firmware to the ESP8266. 

Under the settings for the Feather, click UPLOAD.

If everything compiles and uploads successfully, the Feather on the ESPHomeYAML dashboard will display as Online.

Flashing firmware using the Command Line

You can also flash firmware from the command line by following the instructions on the esphomeyaml Getting Started documentation. 

Note: To use the PlatformIO Python dependency required by esphomeyaml CLI - you'll need to install Python 2.7.9. If you don't want to mess with multiple installations of Python on your computer - you can install this version through PyEnv.  

Viewing data with Home Assistant 

From the Home Assistant sidebar, click Configuration

Then, click Integrations.

After connecting, the feather with BME280 will appear under Configured with three icons for the three types of data the BME280 sensor produces - humidity, pressure, and temperature.

Navigating to the Home page should bring up the dashboard with the BME280 temperature, pressure, and humidity displayed. 

Logging Sensor Data with Adafruit IO

Data from the Feather Huzzah sensor is also sent to Adafruit IO every updated_interval seconds.

You can view this data in real-time from the Adafruit IO monitor page:

You can also create an Adafruit IO Dashboard with line graphs to visualize the data from the sensor over multiple weeks.

• For more information about working with dashboards in Adafruit IO, visit the Adafruit IO Basics: Dashboards guide. 

Exporting Adafruit IO Data

If you would like to download all of the stored data from a feed (the BME280's temperature data, for example), you can do so by following this guide.