home-assistant.io/source/_components/sensor.bme280.markdown

layout	title	description	date	sidebar	comments	sharing	footer	logo	ha_category	ha_release	ha_iot_class
page	BME280 Sensor	Instructions on how to integrate a BME280 sensor into Home Assistant.	2017-06-10 00:00	true	false	true	true	raspberry-pi.png	Sensor	0.48	Local Push

The bme280 sensor platform allows you to read temperature, humidity and pressure values of a Bosch BME280 Environmental sensor connected via I2c bus (SDA, SCL pins). It allows you to use all the operation modes of the sensor described in its datasheet.

Tested devices:

• Raspberry Pi

To use your BME280 sensor in your installation, add the following to your configuration.yaml file:

# Example configuration.yaml entry
sensor:
  - platform: bme280

Configuration variables:

• name (Optional): The name of the sensor
• i2c_address (Optional): I2c address of the sensor. It is 0x76 or 0x77.
• i2c_bus (Optional): I2c bus where the sensor is. Defaults to 1, for Raspberry Pi 2 and 3.
• operation_mode (Optional): Power mode for the sensor. Use 2 for forced mode or 3 for normal mode. Defaults to normal mode.
• time_standby (Optional): Standby time in ms for normal mode of operation as described in the sensor datasheet. Defaults to 5 ms.
• oversampling_temperature (Optional): Oversampling multiplier as described in the sensor datasheet. Can be 0 (no sampling), 1, 2, 4, 8, or 16. Default is 1.
• oversampling_pressure (Optional): Oversampling multiplier as described in the sensor datasheet. Can be 0 (no sampling), 1, 2, 4, 8, or 16. Default is 1.
• oversampling_humidity (Optional): Oversampling multiplier as described in the sensor datasheet. Can be 0 (no sampling), 1, 2, 4, 8, or 16. Default is 1.
• filter_mode (Optional): IIR filter coeficient as described in the sensor datasheet. Default is 0, for filter off.
• delta_temperature (Optional): Absolute delta for temperature correction.
• monitored_conditions array (Optional): Conditions to monitor. Available conditions are temperature, humidity and pressure. By default all three are displayed.

{% linkable_title Full Examples %}

If you want to specify the working mode of the digital sensor or need to change the default I2c address (which is 0x76), add more details to the configuration.yaml file:

# Example of customized configuration.yaml entry
sensor:
  - platform: bme280
    name: Ambient
    i2c_address: 0x77
    operation_mode: 2  # forced mode
    time_standby: 5
    oversampling_temperature: 4
    oversampling_pressure: 4
    oversampling_humidity: 4
    delta_temperature: -0.5
    monitored_conditions:
      - temperature
      - humidity
      - pressure
    scan_interval: 40

This sensor is somehow famous for generating relatively high temperature measurements compared to other sensors (it looks like self-heating does not feel good for some encapsulations). If you experience this problem, you can define an absolute delta of temperature correction using a negative number.

{% linkable_title Customizing the sensor data %}

Give the values friendly names and icons, add the following to your customize: section.

# Example configuration.yaml entry
customize:
  sensor.ambient_temperature:
    icon: mdi:thermometer
    friendly_name: "Temperature"
  sensor.ambient_humidity:
    icon: mdi:weather-rainy
    friendly_name: "Humidity"
  sensor.ambient_pressure:
    icon: mdi:gauge
    friendly_name: "Pressure"

To create a group, add the following to your groups section.

# Example configuration.yaml entry
group:
  ambient_sensor:
    name: BME280 Environment sensor
    entities:
      - sensor.ambient_temperature
      - sensor.ambient_humidity
      - sensor.ambient_pressure

{% linkable_title Directions for installing smbus support on Raspberry Pi %}

Enable I2c interface with the Raspberry Pi configuration utility:

# pi user environment: Enable i2c interface
$ sudo raspi-config

Select Interfacing options->I2C choose <Yes> and hit Enter, then go to Finish and you'll be prompted to reboot.

Install dependencies for use the smbus-cffi module and enable your homeassistant user to join the i2c group:

# pi user environment: Install i2c dependencies and utilities
$ sudo apt-get install build-essential libi2c-dev i2c-tools python-dev libffi-dev

# pi user environment: Add homeassistant user to the i2c group
$ sudo addgroup homeassistant i2c

# pi user environment: Reboot Raspberry Pi to apply changes
$ sudo reboot

{% linkable_title Check the i2c address of the sensor %}

After installing i2c-tools, a new utility is available to scan the addresses of the connected sensors:

$ /usr/sbin/i2cdetect -y 1

It will output a table like this:

     0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
00:          -- -- -- -- -- -- -- -- -- -- -- -- --
10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
20: -- -- -- 23 -- -- -- -- -- -- -- -- -- -- -- --
30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
40: 40 -- -- -- -- -- UU -- -- -- -- -- -- -- -- --
50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
70: -- -- -- -- -- -- -- 77

So you can see the sensor address what you are looking for is 0x77 (there are more i2c sensors in that Raspberry Pi).