Key telephone system

Claim 1

A key telephone system including a plurality of key telephone stations of a first type, a switching network for connecting said key telephone stations to CO/PBX or intercom telephone lines, and system control means for controlling said key telephone stations and said switching network in accordance with system data stored in system data memory means, and further including a key telephone station of a second type operable in a first mode as a key telephone station of the first type and in a second mode as an input means for setting system data in said system data memory means, and menu memory means in which are stored in advance a plurality of combinations of system data, prepared for each kind of service, wherein said system control means effects control, on the basis of system data selected to control operation of the key telephone stations as key telephone stations of the first type, by loading said system data memory means with system data selected from said menu memory means by push-button operation of said key telephone station of the second type in said system data setting mode; wherein said key telephone station of the second type includes function buttons generating function codes and dial buttons generating numerical codes; said system control means includes a mode memory section for designating either said first mode or said second mode, and a menu number memory section, responsive to said dial buttons for designating a menu number, the contents of which re to be written into the system data memory means; said menu memory means including a read only memory array, a data read port, and an address selector responsive to the menu number stored in said menu number memory section and; wherein said system data memory includes a random access memory array, an address selector responsive to address information from a selected menu address for addressing areas in said random access memory array, a data read/write port, a buffer memory storing data from the selected menu address, gate means responsive to a function button of said key telephone station of the second type for selectively passing data stored in said buffer means to said data read/write port, whereby data from the selected menu address is written into the random access memory array at the address designated by said system data address selector in response to address information received from the selected menu address.