Added documentation for bl0942 (#2286)

components/sensor/bl0942.rst

@@ -0,0 +1,68 @@
+Belling BL0942 Energy Monitor
+==================================
+
+.. seo::
+    :description: Instructions for setting up BL0942 power monitors.
+    :image: bl0942.png
+    :keywords: BL0942, Aubess, Mini Smart Switch With Energy Monitor
+
+The ``bl0942`` sensor platform allows you to use BL0942 energy monitors sensors with
+ESPHome. These are used in some Tuya-devices (e.g. Aubess Tuya WiFi Mini Smart Switch With Energy Monitor)
+
+The communication with this integration is done over a :ref:`UART bus <uart>`.
+You must therefore have a ``uart:`` entry in your configuration with both the TX and RX pins set
+to some pins on your board and the baud rate set to 4800 with 1 stop bit.
+
+.. code-block:: yaml
+
+    # Example configuration entry
+    uart:
+      id: uart_bus
+      tx_pin: TX
+      rx_pin: RX
+      baud_rate: 4800
+      stop_bits: 1
+
+    sensor:
+      - platform: bl0942
+        uart_id: uart_bus
+        voltage:
+          name: 'BL0942 Voltage'
+        current:
+          name: 'BL0942 Current'
+        power:
+          name: 'BL0942 Power'
+          filters:
+            multiply: -1
+        energy:
+          name: 'BL0942 Energy'
+        frequency:
+          name: "BL0942 Frequency"
+          accuracy_decimals: 2
+
+        update_interval: 60s
+
+Configuration variables:
+------------------------
+
+- **voltage** (*Optional*): The voltage value of the sensor in Volts.
+  All options from :ref:`Sensor <config-sensor>`.
+- **current** (*Optional*): The current value of the sensor in Amperes. All options from
+  :ref:`Sensor <config-sensor>`.
+- **power** (*Optional*): The (active) power value of the sensor in Watts. Note that some power meters will report this in negative values (probably wired backwards), so you may want to use a filter to multiply it by -1. All options from :ref:`Sensor <config-sensor>`. 
+- **energy** (*Optional*): Use the voltage value of the sensor in kWh.
+  All options from :ref:`Sensor <config-sensor>`.
+- **frequency** (*Optional*): The frequency value of the sensor in Hertz. All options from
+  :ref:`Sensor <config-sensor>`.
+  All options from :ref:`Sensor <config-sensor>`.
+- **update_interval** (*Optional*, :ref:`config-time`): The interval to check the
+  sensor. Defaults to ``60s``.
+- **uart_id** (*Optional*, :ref:`config-id`): Manually specify the ID of the :ref:`UART Component <uart>` if you want
+  to use multiple UART buses.
+
+See Also
+--------
+
+- :ref:`sensor-filters`
+- :apiref:`bl0942/bl0942.h`
+- :ghedit:`Edit`

index.rst

@@ -255,6 +255,7 @@ Electricity
     ATM90E32, components/sensor/atm90e32, atm90e32.jpg, Voltage & Current & Power
     BL0939, components/sensor/bl0939, bl0939.png, Voltage & Current & Power & Energy
     BL0940, components/sensor/bl0940, bl0940.png, Voltage & Current & Power
+    BL0942, components/sensor/bl0942, bl0942.png, Voltage & Current & Power
     CS5460A, components/sensor/cs5460a, cs5460a.png, Voltage & Current & Power
     CSE7761, components/sensor/cse7761, cse7761.svg, Voltage & Current & Power
     CSE7766, components/sensor/cse7766, cse7766.svg, Voltage & Current & Power