TELEPHONE SET TERMINAL INTERFACE DEVICE

PURPOSE:To allow each small telephone set terminal group to receive various additional services used by a telephone set terminal without the need for direct processing by a central controller provided to an exchange. CONSTITUTION:This device is provided with a telephone interface circuit 16 to which lots of telephone set terminals are connected and which includes a means separating voice information and control information, an operation information transmission 14 fetching dial button operation information from the telephone interface circuit 16 and sending the information to an exchange, and a terminal control means 13 giving terminal control information to the telephone interface circuit 16. As to operation information requiring a specific additional service, the destination of the operation information is selected to be another terminal in place of a terminal leading to the exchange and a computer receives the control information being the transmission information to execute the additional service.