Eidolons go unconscious at negative HP right?

[Frosty]

Assuming that is the case, how is an eidolon supposed to use aHarness, Eidolon Anchoring (http://www.d20pfsrd.com/magic-items/wondrous-items/wondrous-items/h-l/harness-eidolon-anchoring) assuming it doesn't have Diehard? I mean, it needs to take an action (albeit a free one) in order to use it, and if it's unconscious, then it can't use it right?

[TuggyNE]

They should have made it an immediate action, or a free action that takes effect before the trigger, or similar. As it is it just doesn't work at all, since the eidolon is already gone.

[grarrrg]

One of the main uses would be if the Summoner dropped unconscious (whether through Spell or negative HP), then the Eidolon would normally be sent back instantly, but would otherwise still be able to take actions.

Pretty sure they fall unconscious just like everybody else below 0, but I'm too tired to go digging.