OUTGOING*INCOMING CONTROL SYSTEM OF KEY TELEPHONE SET

摘要

PURPOSE:To make it possible to set originating control individually only through switch operation by judging the outgoing/incoming control of a main wire that corresponds to a line bus by a main control unit and by exercising connection control over key telephone sets. CONSTITUTION:Outgoing/incoming control unit OAD is provided which has diodes D and switch circuits DSO1-DSOn and DSA1-DSAn into respective intersections between line buses Y1-Y4 and Y11-Y14 that correspound to main wires and telephone-set bus X1-Xn that corresponds to key telephone sets MFT1-MFTn. Originating control of main wires that correspond to line buses Y1-Y4 and Y11-Y14 with regard to key telephone sets is judged by main control unit MCU to exercise connection control over telephone sets MFT1-MFTn. Consequently, the originating control can individually be set only through switch operation.