40d:Lever

A lever is a device that can be linked to other devices to control them. A lever is pulled through its q menu with aP. A nearby dwarf will then pull it. Pressure plates are like levers, but are activated automatically by creatures stepping on it.

Levers have an 'on' and a 'off' state. Upon being flipped, everything they're connected to updates to the lever's new state. This becomes important if you have several levers attached to the same building.

Furthermore, there's a delay when sending the update signal: If you pull a lever on then off too fast, it will only send the 'off' signal.

Objects that can be controlled by levers include:

Multiple Uses

• Bridge
  • On: Turns the bridge into either a raised drawbridge, or a retracted bridge, depending on which option was chosen when the the bridge was constructed.
  • Off: Returns the bridge to normal.

• Door – Note that once you connect a door, it is either completely open, or locked. There is no "closed, but can be opened by a dwarf" state anymore.
  • On: Opens the door.
  • Off: Closes the door.

• Floodgate – After the lever is installed, it works exactly like a door.
  • On: Opens the floodgate.
  • Off: Closes the floodgate.

• Hatch – When open it just disappears and allows water through. Note it is suspected that like doors - once you connect a hatch, it is either completely open, or locked.
  • On: Opens the hatch.
  • Off: Closes the hatch.

• Grate – When it is open, it just disappears. Water goes through it just the same, but it cannot be walked on anymore. Anybody on it will probably fall through^[Verify].
  • On: Opens the grate.
  • Off: Closes the grate.

• Upright Spear/Spikes
  • On: Retracts spears/spikes.^[Verify]
  • Off: Extends spears/spikes.^[Verify]

• Gear assembly – When it is disengaged, no power goes through it and anything that is being kept up by its presence (like a windmill right on top of it) falls down.
  • On: Disengages the gear assembly.
  • Off: Engages the gear assembly.

One-Shot

• Cage/Restraint – Opens the cage/chain/rope and releases whatever it held. This is permanent and you will have to reinstall and relink the cages/restraints after one use. You recover the mechanism used in the cage/restraint.

• Support – Deconstructs the support, except without a dwarf next to it. Most commonly used to effect cave-ins.

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