Documentation for MAX31855 sensor (#97)

* MAX 31855 documentation

* Fix link

* Update image

api/sensor/max31855.rst

@@ -0,0 +1,16 @@
+MAX31855 K-Type Thermocouple Temperature Sensor
+===============================================
+
+.. cpp:namespace:: nullptr
+
+See :cpp:func:`Application::make_max31855_sensor`.
+
+API Reference
+-------------
+
+.. cpp:namespace:: nullptr
+
+.. doxygenclass:: sensor::MAX31855Sensor
+    :members:
+    :protected-members:
+    :undoc-members:

esphomeyaml/components/sensor/max31855.rst

@@ -0,0 +1,59 @@
+MAX31855 K-Type Thermocouple Temperature Sensor
+===============================================
+
+.. seo::
+    :description: Instructions for setting up MAX31855 Thermocouple temperature sensors.
+    :image: max31855.jpg
+
+The ``max31855`` temperature sensor allows you to use your max31855 thermocouple
+temperature sensor (`datasheet <https://datasheets.maximintegrated.com/en/ds/MAX31855.pdf>`__) with esphomelib
+
+As the communication with the MAX66775 is done using SPI, you need
+to have an :ref:`spi bus <spi>` in your configuration with the **miso_pin** set (mosi is not required).
+
+Connect ``GND`` to ``GND``, ``VCC`` to ``3.3V`` and the other three ``MISO`` (or ``SO`` for short),
+``CS`` and ``CLOCK`` (or ``CLK``) to free GPIO pins.
+
+.. figure:: images/temperature.png
+    :align: center
+    :width: 80.0%
+
+.. code:: yaml
+
+    # Example configuration entry
+    spi:
+      miso_pin: D0
+      clk_pin: D1
+
+    sensor:
+      - platform: max31855
+        name: "Living Room Temperature"
+        cs_pin: D2
+        update_interval: 15s
+
+Configuration variables:
+------------------------
+
+- **name** (**Required**, string): The name for the temperature sensor.
+- **cs_pin** (**Required**, :ref:`Pin Schema <config-pin_schema>`): The Chip Select pin of the SPI interface.
+- **update_interval** (*Optional*, :ref:`config-time`): The interval to check the sensor. Defaults to ``15s``.
+  See :ref:`sensor-default_filter`.
+- **spi_id** (*Optional*, :ref:`config-id`): Manually specify the ID of the :ref:`SPI Component <spi>` if you want
+  to use multiple SPI buses.
+- **id** (*Optional*, :ref:`config-id`): Manually specify the ID used for code generation.
+- All other options from :ref:`Sensor <config-sensor>` and :ref:`MQTT Component <config-mqtt-component>`.
+
+See Also
+--------
+
+- :ref:`sensor-filters`
+- :doc:`dallas`
+- :doc:`dht`
+- :doc:`adc`
+- :doc:`sht3xd`
+- :doc:`max6675`
+- `MAX31855 Library <https://github.com/adafruit/Adafruit-MAX31855-library>`__ by `Adafruit <https://www.adafruit.com/>`__
+- :doc:`API Reference </api/sensor/max31855>`
+- `Edit this page on GitHub <https://github.com/OttoWinter/esphomedocs/blob/current/esphomeyaml/components/sensor/max31855.rst>`__
+
+.. disqus::

esphomeyaml/index.rst

@@ -95,6 +95,7 @@ Sensor Components
     INA219, components/sensor/ina219, ina219.jpg
     INA3221, components/sensor/ina3221, ina3221.jpg
     HTU21D, components/sensor/htu21d, htu21d.jpg
+    MAX31855, components/sensor/max31855, max31855.jpg
     MAX6675, components/sensor/max6675, max6675.jpg
     MH-Z19, components/sensor/mhz19, mhz19.jpg
     MPU6050, components/sensor/mpu6050, mpu6050.jpg