Nextion Sensor Component

The nextion sensor platform supports integers or floats (Xfloat). It can be a component, a variable or a waveform in the Nextion display. It is best to set the component’s vscope to global in the Nextion Editor. This way the component will be available if the page is shown or not.

Note

The Nextion can receive an integer but it can only send 3 bytes for a negative integer. The range if using the Nextion Custom Sensor Protocol is:

-16777215 to 4294967295

See Nextion TFT LCD Display for setting up the display

# Example configuration entry
display:
  - platform: nextion
    id: nextion1
    # ...

sensor:
  - platform: nextion
    name: "Current Humidity"
    component_name: humidity # pageX.humidity for a global
    precision: 1
    update_interval: 4s
  - platform: nextion
    nextion_id: nextion1
    name: "Current Temperature"
    variable_name: temperature
  - platform: nextion
    id: s01
    component_id: 2
    wave_channel_id: 0
    wave_max_value: 100
    waveform_send_last_value: "true"
    wave_max_length: 400
    update_interval: 1s
  - platform: nextion
    id: s02
    component_id: 2
    wave_channel_id: 1
    wave_max_value: 100
    update_interval: 1s

Configuration variables:

  • nextion_id (Optional, ID): Manually specify the ID of the Nextion display.

  • component_name (Optional, string): Manually specify the name of the Nextion component.

  • variable_name (Optional, string): Manually specify the name of the Nextion variable.

  • update_interval (Optional, Time): The duration to update the sensor

  • precision (Optional, int): This is for Nextion float components. This sets the precision that the component is set to. This typically is the vvs1 setting of the component.

  • background_color (Optional, Color): The background color

  • foreground_color (Optional, Color): The foreground color

  • visible (Optional, boolean): Visible or not

Waveform Settings

  • wave_channel_id (Optional, int): The waveform ID in a range of 0-3

  • wave_max_value (Optional, int): The max value. Set dis to the height of the component in the Nextion editor and this to the max value that will be sent. This will set up the proper scaling.

  • waveform_send_last_value (Optional, int): This will send the last value set during an update interval. Setting to true will give a timeseries style graph

  • wave_max_length (Optional, int): How many data points to store. Typically this is the width of the component in the Nextion

  • update_interval (Optional, Time): The duration to update the sensor. This typically should be set for waveforms to send periodic updates.

  • All other options from Sensor.

Only one component_name or variable_name can be set

Note

background_color , foreground_color and visible do not retain their state on page change. Sensor Settings. A Nextion Sensor with a custom protocol sending the current page can be used to execute the API call Update Components By Prefix to update all the components for that page

See How things Update for additional information

Globals

The Nextion does not retain data on Nextion page changes. Additionally if a page is changed and the component_name does not exist on that page then nothing will be updated. To get around this the Nextion components can be changed to have a vscope of global. If this is set then the component_name should be prefixed with the page name (page0/page1 or whatever you have changed it to).

Example

component_name: page0.humidity

sensor.nextion.publish Action

You can also publish a state to a Nextion sensor from elsewhere in your YAML file with the sensor.nextion.publish action.

# Example configuration entry
sensor:
  - platform: nextion
    id: nextion_sensor
    ...
# in some trigger
on_...:
  - sensor.nextion.publish:
      id: nextion_sensor
      state: 100.0
      # These are optional. Defaults to true.
      publish_state: true
      send_to_nextion: true
  # Templated
  - sensor.nextion.publish:
      id: nextion_sensor
      state: !lambda 'return 100.0;'
      # These are optional. Defaults to true.
      publish_state: true
      send_to_nextion: true

Configuration variables:

  • id (Required, ID): The ID of the Nextion sensor.

  • state (Required, string, templatable): The float state to publish.

  • publish_state (Optional, bool, templatable): Publish new state to Home Assistant. Default is true.

  • send_to_nextion (Optional, bool, templatable): Publish new state to Nextion display which will update component. Default is true.

Note

This action can also be written in lambdas. See Lambda Calls

Lambda Calls

From lambdas, you can call several methods to access some more advanced functions (see the full API Reference for more info).

  • set_state(bool value, bool publish, bool send_to_nextion): Set the state to value. Publish the new state to HASS. Send_to_Nextion is to publish the state to the Nextion.

  • update(): Poll from the Nextion

  • set_background_color(Color color): Sets the background color to Color

  • set_foreground_color(Color color): Sets the background color to Color

  • set_visible(bool visible) : Sets visible or not. If set to false, no updates will be sent to the component

How things Update

A Nextion component with an integer value (.val) or Nextion variable will be automatically polled if update_interval is set. To have the Nextion send the data you can use the Nextion Custom Sensor Protocol for this. Add the Nextion Custom Sensor Protocol to the component or function you want to trigger the send. Typically this is in Touch Press Event but some components, like a slider, should have it set in the Touch Release Event to capture all the changes. Since this is a custom protocol it can be sent from anywhere (timers/functions/components) in the Nextion.

Note

There is no need to check the Send Component ID for the Touch Press Event or Touch Release Event since this will be sending the real value to esphome.

Using the above yaml example:

  • “Current Humidity” will poll the Nextion for the humidity.val value and set the sensor accordingly.

  • “Current Temperature” will NOT poll the Nextion. Either the Nextion will need to use the Nextion Custom Sensor Protocol or use a lambda:

Note

No updates will be sent to the Nextion if it is sleeping. Once it wakes, the components will be updated. If a component is invisible, visible(false), then it won’t update until it is set to be visible.

Nextion Custom Sensor Protocol

All lines are required

printh 91
prints "temperature",0
printh 00
prints temperature.val,0
printh FF FF FF

Explanation

  • printh 91 Tells the library this is a sensor (int) data

  • prints "temperature",0 Sends the name that matches component_name or variable_name

  • printh 00 Sends a NULL

  • prints temperature.val,0 The actual value to send. For a variable use the Nextion variable name temperature with out .val

  • printh FF FF FF Nextion command ack

See Also