Methods, devices, and systems for laser eye surgery generally make use of a console that interchangeably accepts multiple types of eye treatment cassettes. The cassettes enable one or both of displacement-based or vacuum-based aspiration. The console and the cassette may communicate to establish the functionality of the installed cassette by utilizing a component indigenous to the operation of the cassette. A dual-mode cassette may include a separable holding tank for enabling vacuum-based aspiration. A displacement-based pump may be provided to drain the holding tank while the vacuum system continues to aspirate fluids. A vacuum sensor for controlling the flow of aspirated fluids may have three ports for communicating with a handpiece, a displacement-based pump, a vacuum-based pump, or an irrigation source. The handpiece may be vented during vacuum-based aspiration by opening a vent valve interposed between the handpiece and the vacuum source.
