Esphome and xiaomi LYWSD03MMC sensor and lambda values

ESPHome
1

Hi team…

I have a display connected to my ESP32. I want to display current temperature/humidity values on that display… while the ESP pushes data to MQTT/HomeAssistant etc.

My sensor is defined as :slight_smile: sensor:

  - platform: atc_mithermometer
    id: sensor_kitchen
    mac_address: "A4:C1:38:13:30:17"
    temperature:
      name: "xTemperature Kitchen"
      id: kitchen_temp
    humidity:
      name: "xHumidity Kitchen"
    battery_level:
      name: "xBattery Kitchen"
    battery_voltage:
      name: "xBattery Voltage Kitchen"

The display has coded as below

display:
  - platform: ssd1306_i2c
    model: "SSD1306 64x48"
    reset_pin: 26  #GPIO26 #D0
    address: 0x3C
    lambda: |-
      it.print(0, 0, id(my_font), id(my_light_green), "DGW ESP32 1");
      it.strftime(0, 10, id(my_font), "%d--%H:%M:%S", id(sntp_time).now());
      it.print(0, 20, id(my_font), "Kitchen:  %.2f", id(sensor_kitchen).state);

And the compile fails with:
Compiling .pioenvs/sensoresp32/src/main.cpp.o
src/main.cpp: In lambda function:
src/main.cpp:544:66: error: ‘class esphome::atc_mithermometer::ATCMiThermometer’ has no member named ‘state’
it.print(0, 20, my_font, “Kitchen: %.2f”, sensor_kitchen->state);
^
*** [.pioenvs/sensoresp32/src/main.cpp.o] Error 1

Can I do what I want to do?
If not, is there a work around?

  • David
2

I suspect you want kitchen_temp not sensor_kitchen in your print lambda.

3

Sorry… my bad… too many code changes… that doesn’t work. More spectacular compiler error though!

      it.print(0, 20, id(my_font), "Kitchen:  %.2f", id(kitchen_temp).state);

Compiling .pioenvs/sensoresp32/src/main.cpp.o
src/main.cpp: In lambda function:
src/main.cpp:545:69: error: no matching function for call to 'esphome::display::DisplayBuffer::print(int, int, esphome::display::Font*&, const char [15], float&)'
       it.print(0, 20, my_font, "Kitchen:  %.2f", kitchen_temp->state);
                                                                     ^
In file included from src/esphome.h:14:0,
                 from src/main.cpp:3:
src/esphome/components/display/display_buffer.h:139:8: note: candidate: void esphome::display::DisplayBuffer::print(int, int, esphome::display::Font*, esphome::Color, esphome::display::TextAlign, const char*)
   void print(int x, int y, Font *font, Color color, TextAlign align, const char *text);
        ^
4

Hi

I think you need to use printf and not print in the lambda. If you are printing values.

/Mattias

5

Interesting. Do you know of any code examples or documentation that shows how to do this?

6

It in the esphome dokumentation.

In the section
Formatted Text

There you have an example and documentation.

From the documentation


display:
  - platform: ...
    # ...
    lambda: |-
      it.printf(0, 0, id(my_font), "The sensor value is: %.1f", id(my_sensor).state);
      // If the sensor has the value 30.02, the result will be: "The sensor value is: 30.0"

Basically it seems that you only missing a the f in print statement.

/Mattias

7

Right. Understood. Will try when I get home from work.

8

That’s awesome and I can confirm it’s working. Thank you so kindly for your help.

9

Great that it works.
/Mattias