In general, in one aspect, the disclosure describes a device to enable a user to move a toilet seat from an up position to a down position. The two states are selected to be the furthest separated of the multiple states, thereby providing an increased margin during two state operation. identify one or more treatment regions based upon the boundaries; and operate the optical scanning system with the pulsed laser to produce a treatment beam directed in a pattern based on the one or more treatment regions. The transmitting mobile terminal may enable retransmission of at least one previously transmitted PDU in the PDU sequence based on the failure indication.