Serial Sensor Topic with multiple sensors

Configuration
1

Hi, I am attempting to configure multiple DS18B20 sensors that are read serially (json formatted) from a connected Arduino. The serial data from the arduino looks like this:

image
image616×322 7.97 KB

My configuration.yaml entry looks like this:

Example configuration.yaml entry

sensor:

  • platform: serial
    serial_port: /dev/ttyUSB0
    baudrate: 9600

Use template sensors to parse the data.

template:

  • sensor:
    • name: “28AA35F0541401C6”
      unit_of_measurement: “°F”
      device_class: temperature
      state: >
      {% if {{ state_attr(‘sensor.serial_sensor’, ‘sensor’) }} == ‘28AA35F0541401C6’ %}
      # update the sensor value with the new value
      {{ state_attr(‘sensor.serial_sensor’, ‘value’) }}
      {% else %}
      #no match so keep the current data
      {% endif %}
    • name: “28AA6819551401CE”
      unit_of_measurement: “°F”
      device_class: temperature
      state: >
      {% if {{ state_attr(‘sensor.serial_sensor’, ‘sensor’) }} == ‘28AA6819551401CE’ %}
      # update the sensor value with the new value
      {{ state_attr(‘sensor.serial_sensor’, ‘value’) }}
      {% else %}
      #no match so keep the current data
      {% endif %}

This logic appears to completely fail and then neither of the values get updated at all. Any help would be appreciated. thanks in advance!

2

Please format your configuration properly.

f6be36681e0da431418ec7781fb6c62712941803

You are nesting templates, which isn’t allowed.

{% if state_attr('sensor.serial_sensor', 'sensor') == '28AA6819551401CE' %}

Then you will need to use the self-referencing variable this in the else or you will end up without a state most of the time.

3

Thank you… can you propose how better to handle this?

4

I already did… Look at the quoted portion from your original post and what I posted… you need to remove the expression delimiters {{ }} that are inside your statement delimiters {% %}.

5

apologies… i see that now… and thanks for the tip on posting

ok i have the new configuration as this:

sensor:
  - platform: serial
    serial_port: /dev/ttyUSB0
    baudrate: 9600
# Use template sensors to parse the data.
template:
  - sensor:
      - name: "28AA35F0541401C6"
        unit_of_measurement: "°F"
        device_class: temperature
        state: >
            {% if state_attr(‘sensor.serial_sensor’, ‘sensor’) == ‘28AA6819551401C6’ %}
               # update the sensor value with the new value
               {{ state_attr('sensor.serial_sensor', 'value') }}
            {% else %}
                {{ this.state }}
            {% endif %}
      - name: "28AA6819551401CE"
        unit_of_measurement: "°F"
        device_class: temperature
        state: >
            {% if state_attr(‘sensor.serial_sensor’, ‘sensor’) == ‘28AA6819551401CE’ %}
               # update the sensor value with the new value
               {{ state_attr('sensor.serial_sensor', 'value') }}
            {% else %}
                {{ this.state }}
            {% endif %}

This still is not updating the values at all

6

You haven’t provided tests and defaults for the first run where this is not defined…

I would recommend switching to trigger-based template sensors instead of state-based. Since your Serial sensor provides an attribute for the sensor ID, you could uses distinct State triggers for each one instead of needing if/then and self-referencing.

template:
  - triggers:
      - trigger: state
        entity_id: sensor.serial_sensor
        attribute: sensor
        to: 28AA35F0541401C6
    sensor:
      - name: '28AA35F0541401C6'
        unit_of_measurement: '°F'
        device_class: temperature 
        state: "{{ trigger.to_state.attributes.value }}" 
  - triggers:
      - trigger: state
        entity_id: sensor.serial_sensor
        attribute: sensor
        to: 28AA6819551401CE
    sensor:
      - name: '28AA6819551401CE'
        unit_of_measurement: '°F'
        device_class: temperature
        state: "{{ trigger.to_state.attributes.value }}"
1 Like
7

Ok switching to trigger-based template sensors seems to do exactly what I want… I will keep playing with it… Thanks so much!