Add docs for SCD4X (#1429)

* Initial commit

* Fix title underline length

* Add SCD4X to environmental list

Co-authored-by: Oxan van Leeuwen <oxan@oxanvanleeuwen.nl>

components/sensor/scd4x.rst

@@ -0,0 +1,82 @@
+SCD4X CO₂, Temperature and Relative Humidity Sensor
+===================================================
+
+.. seo::
+    :description: Instructions for setting up SCD4X CO₂ Temperature and Relative Humidity Sensor
+    :image: scd4x.jpg
+
+The ``scd4x`` sensor platform  allows you to use your Sensirion SCD4X CO₂
+(`datasheet <https://www.sensirion.com/fileadmin/user_upload/customers/sensirion/Dokumente/9.5_CO2/Sensirion_CO2_Sensors_SCD4x_Datasheet.pdf>`__) sensors with ESPHome.
+The :ref:`I²C Bus <i2c>` is required to be set up in your configuration for this sensor to work.
+
+.. figure:: images/scd4x.jpg
+    :align: center
+    :width: 80.0%
+
+.. code-block:: yaml
+
+    # Example configuration entry
+    sensor:
+      - platform: scd4x
+        co2:
+          name: "Workshop CO2"
+        temperature:
+          name: "Workshop Temperature"
+        humidity:
+          name: "Workshop Humidity"
+
+
+Configuration variables:
+------------------------
+
+- **co2** (*Optional*): The information for the CO₂ sensor.
+
+  - **name** (**Required**, string): The name for the CO₂eq sensor.
+  - **id** (*Optional*, :ref:`config-id`): Set the ID of this sensor for use in lambdas.
+  - All other options from :ref:`Sensor <config-sensor>`.
+
+- **temperature** (*Optional*): The information for the Temperature sensor.
+
+  - **name** (**Required**, string): The name for the temperature sensor.
+  - **id** (*Optional*, :ref:`config-id`): Set the ID of this sensor for use in lambdas.
+  - All other options from :ref:`Sensor <config-sensor>`.
+
+
+- **humidity** (*Optional*): The information for the Humidity sensor.
+
+  - **name** (**Required**, string): The name for the humidity sensor.
+  - **id** (*Optional*, :ref:`config-id`): Set the ID of this sensor for use in lambdas.
+  - All other options from :ref:`Sensor <config-sensor>`.
+
+- **temperature_offset** (*Optional*, float):  The temperature offset can depend
+  on various factors such as the SCD4x measurement mode, self-heating of close
+  components, the ambient temperature and air flow. This variable allows the
+  compensation of those effects by setting a temperature offset. Defaults to
+  ``4°C``.
+
+- **automatic_self_calibration** (*Optional*, bool): Whether to enable
+  automatic self calibration (ASC). Defaults to ``true``.
+
+- **ambient_pressure_compensation** (*Optional*, int): Enable compensation
+  of measured CO₂ values based on given ambient pressure in mBar.
+
+- **altitude_compensation** (*Optional*, int): Enable compensating
+  deviations due to current altitude (in metres). Notice: setting
+  *altitude_compensation* is ignored if *ambient_pressure_compensation*
+  is set.
+
+- **address** (*Optional*, int): Manually specify the I²C address of the sensor.
+  Defaults to ``0x62``.
+
+- **update_interval** (*Optional*, :ref:`config-time`): The interval to check the
+  sensor. Defaults to ``60s``.
+
+
+
+See Also
+--------
+
+- :ref:`sensor-filters`
+- :doc:`scd30`
+- :apiref:`scd4x/scd4x.h`
+- :ghedit:`Edit`

index.rst

@@ -180,6 +180,7 @@ Air Quality
     SDS011 Sensor, components/sensor/sds011, sds011.jpg, Particulate
     SenseAir, components/sensor/senseair, senseair_s8.jpg, CO2
     SCD30, components/sensor/scd30, scd30.jpg, CO2 & Temperature & Humidity
+    SCD4X, components/sensor/scd4x, scd4x.jpg, CO2 & Temperature & Humidity
     SGP30, components/sensor/sgp30, sgp30.jpg, CO2 & Volatile organics
     SGP40, components/sensor/sgp40, sgp40.jpg, Volatile organics
     SM300D2, components/sensor/sm300d2, sm300d2.jpg, Air quality
@@ -280,6 +281,7 @@ Environmental
     NTC Thermistor, components/sensor/ntc, ntc.jpg, Temperature
     RuuviTag, components/sensor/ruuvitag, ruuvitag.jpg, Temperature & Humidity & Accelerometer
     SCD30, components/sensor/scd30, scd30.jpg, CO2 & Temperature & Humidity
+    SCD4X, components/sensor/scd4x, scd4x.jpg, CO2 & Temperature & Humidity
     SDP3x, components/sensor/sdp3x, sdp31.jpg, Pressure
     SHT3X-D, components/sensor/sht3xd, sht3xd.jpg, Temperature & Humidity
     SHT4X, components/sensor/sht4x, sht4x.jpg, Temperature & Humidity