7 years ago rhet0rica:
HUD says button-probe (if device's type not already recognized)
  => device says add-section <name> <button_count>
=> HUD says add-section-confirm <name>
  => device says add-button <name> <image> <command>
    => HUD says add-button-confirm <name> or add-button-fail <name> (if section is already full)

<name> is always the device's name (as with other active light bus messages)—other values would work but can't be removed from the HUD
<command> is sent as an internal 1 COMMAND with the unit's key.