Data input/output system for gasoline stations

Claim 1

A data input/output system for gasoline stations, comprising a fuel dispensation control panel having a fuel dispensation request lamp operated by a fuel dispensation request signal from a concerned fuel dispenser, a fuel dispensation permission switch for making operable the concerned dispenser, and a fuel dispensation completion lamp operated by a signal from the concerned dispenser; a key board for inputing sales data of dispensed fuel and other merchandise; a display for indicating said data; a printer for printing said data on a slip; a cash box for accommodating cash, checks and the like; alarm means for issuing an alarm signal; and a control unit having a central processing unit (CPU), a memory unit, a display and key controller, a serial communication interface for the fuel dispensers, and a printer controller, said memory unit having an alarm issuance monetary amount area in which a predetermined amount of money is memorized along with means for setting in said predetermined amount in said alarm issuance monetary amount area, said memory unit also having an area for recording the existing amount of cash accommodated in the cash box, said central processing unit having means for arithmetically increasing and decreasing the record of the amount of cash in the existing amount recording area corresponding to the amount of cash placed into and taken out of the cash box, and means for comparing said recorded amount of cash with said predetermined amount of money in the alarm issuance monetary area at each change in the recorded amount of cash and to issue a signal when the former amounts exceeds the latter amount so as to actuate said alarm means.