Template Cover usage in Homekit

Hi all,

Newbie here. Did some searching on the forum, but couldn’t find the answers I’m looking for.

I’m aiming to control my covers (screens) from homekit via home assistant.

Hardware: Somfy motors, home IO wireless, Somfy Tahoma Switch box (Overkiz)
Software: Home Assistant 2023.4.2, Supervisor 2023.04.0, Operating System 9.5, Overkiz integration

Initial issue: Some Somfy screens work in reverse in Home Assistant. The larger screens are identified as ‘Awnings’ in the Somfy App. Both in the Somfy App and the Somfy remote these work well (Up is Up, Down is Down), but in Homekit this is reversed. As far as I can tell this is a known issue.

To mitigate this I’ve created a cover template, to reverse the direction of the screen in Home Assistant.

- platform: template
  covers:
    screensix:
      friendly_name: Screen Six Reverse
      position_template: "{{ 100 - (state_attr('cover.screensix', 'current_position') | int) }}"
      open_cover:
        service: cover.close_cover
        data:
          entity_id: cover.screensix
      close_cover:
        service: cover.open_cover
        data:
          entity_id: cover.screensix
      stop_cover:
        service: cover.stop_cover
        data:
          entity_id: cover.screensix
      set_cover_position:
        service: cover.screensix
        data:
          entity_id: cover.screensix
          position: "{{ 100 - (position) }}"
    big_screen:
      friendly_name: Big Screen Reverse
      position_template: "{{ 100 - (state_attr('cover.big_screen', 'current_position') | int) }}"
      open_cover:
        service: cover.close_cover
        data:
          entity_id: cover.big_screen
      close_cover:
        service: cover.open_cover
        data:
          entity_id: cover.big_screen
      stop_cover:
        service: cover.stop_cover
        data:
          entity_id: cover.big_screen
      set_cover_position:
        service: cover.big_screen
        data:
          entity_id: cover.big_screen
          position: "{{ 100 - (position) }}"          

This works great in Home Assistant.

However when I expose this cover template via a Homekit bridge, the cover does appear, but it doesn’t respond to up or down commands via Homekit (phone / laptop)

So I can’t seem to figure out how to send a position command from Home assistant to my screen / cover

Up / Down commands work fine. As the the ‘MyPosition’ button. However I can’t find a ‘go to 50%’ command.