Controlling a Bluetooth LED strip with HA

Configuration
17

Hi guys,

Wanted to say thanks for the information in this thread. Inspired me to get an oddball bulb working that I had picked up when it was on sale.

Sengled Smart LED with Bluetooth Speaker Bulb – Sengled Canada - that guy

The tricky bit I had to work around was the bulb expecting brightness between 1-100, but in hex which I solved in my bash script. Then Home Assistant wants to use 1-255… :roll_eyes:

Here’s what I came up with.

#!/bin/bash

sendBluetoothCommand() {
  mac="$mac"
  characteristic="$characteristic"
  commandcode="$1"
  gatttool -i hci0 -b $mac --char-write-req -a $characteristic -n $commandcode
}

mac="01:23:45:67:89:AB"
command="$1"
characteristic=0x0017

case $command in
  volume_up)
    commandcode="7efeffffff0000000000000d000101"
    ;;
  volume_down)
    commandcode="7efeffffff0000000000000d000001"
    ;;
  on)
    commandcode="7efeffffff0000000001000000000000"
    ;;
  off)
    commandcode="7efeffffff0000000001000000000001"
    ;;
  [0-9]|[1-9][0-9]|100)
    hex=$(printf '%02x\n' $1)
    commandcode="7efeffffff00000000010001000000ff$hex"
    ;;
  *)
    echo "Unsupported command!"
    exit 22
    ;;
esac

sendBluetoothCommand $commandcode

Then for the light in home assistant - template to the rescue. Here I convert 1-255 to 1-100 which is what the script is expecting.

  - platform: template
    lights:
      workbench_lamp:
        friendly_name: "Workbench Lamp"
        icon_template: mdi:desk-lamp
        turn_on:
          service: shell_command.sengled_control_on
        turn_off:
          service: shell_command.sengled_control_off
        set_level:
          service: shell_command.sengled_brightness_control
          data:
            brightness: "{{ (brightness | float / 255 * 100) | round(0) }}"

Oh right I also made simple shell command that just calls the script with args specified.

# Sengled Pulse Solo control
sengled_control_on: bash /config/scripts/sengled_control.sh on
sengled_control_off: bash /config/scripts/sengled_control.sh off
sengled_control_volume_up: bash /config/scripts/sengled_control.sh volume_up
sengled_control_volume_down: bash /config/scripts/sengled_control.sh volume_down
sengled_brightness_control: bash /config/scripts/sengled_control.sh {{brightness}}

Magically this all works and made an otherwise useless bulb very useful.

Thanks again everybody! :beers:

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