Ble_client, reading multiple values from the same service_uuid in a decent way

ESPHome
1

I am reading multiple values via Bluetooth from the same Service UUID of a G32 barbeque unit. The way I am doing this is as follows:

  - platform: ble_client
    ble_client_id: ow_g32
    type: characteristic
    name: "G32 Zone 1"
    id: g32_T_1
    service_uuid: 'dc0f41ea-b6ae-46a8-a19e-1a3bf4342bcb'
    characteristic_uuid: 'dc0f41e2-b6ae-46a8-a19e-1a3bf4342bcb'
    device_class: "temperature"
    unit_of_measurement: "°C"
    update_interval: 10s
    lambda: |-
      return (x[6]*10.0+x[7]/10.0);
    on_value:
      - lambda: id(zone1_value) = x;
      - lvgl.widget.refresh: [zone1_label, zone1_arc, zone1_label2]

  - platform: ble_client
    ble_client_id: ow_g32
    type: characteristic
    name: "G32 Zone 2"
    id: g32_T_2
    service_uuid: 'dc0f41ea-b6ae-46a8-a19e-1a3bf4342bcb'
    characteristic_uuid: 'dc0f41e2-b6ae-46a8-a19e-1a3bf4342bcb'
    device_class: "temperature"
    unit_of_measurement: "°C"
    update_interval: 3000s
    lambda: |-
      return (x[8]*10.0+x[9]/10.0);
    on_value:
      - lambda: id(zone2_value) = x;
      - lvgl.widget.refresh: [zone2_label, zone2_arc, zone2_label2]

The update interval shall be 10 seconds. When reading the Service UUID,
the G32 sends the complete data block with 31 bytes containing all the values I need.
So, reading the first value g32_T_1 (first temperature probe) I will get the full 31 bytes (and all values are updated after this read!) and reading the next value g32_T_2 (second temperature probe) I will receive the same 31 bytes again (and update all values again). Reading all (~12) values will read the same 31 bytes 12 times.
This is the reason why I changed the update interval of all other values to a big number.

This is not very elegant. Is there any other way this could be accomplished?

Jörg.

2

I have never used ble_client sensor, so there can be more elegant ways for this, but you can simply pass the data on your lambda to multiple template sensors before return.

3

How would this look like in my example?

4

I don’t have time to get into it right now, but as an example your zone1 sensor lambda could pass zone 2 sensor value to template sensor like this: (just an example, I don’t know what type of data your device outputs).

I hope I made the concept clear.

1 Like
5

I changed my code according to your information and it is much cleaner now!
Thank you very much!

Jörg.

6

Happy to help you.

1 Like