A control system is provided which allows the operator of a marine vessel to select a transmission position and an engine speed in the event that a throttle lever malfunctions. With a typical AWS transceiver placed in close proximity to a PCS transceiver, the AWS device will include a band reject filter to eliminate interference from the PCS signals. When the initial bill is presented, a balance due will be displayed and the indication will be provided that the bill has yet to be paid in full. Therefore, it is possible to improve the reliability of a system to which a semiconductor memory apparatus is applied.