Electronically controlled telephone exchange supervisory board - controls remote equipment through minimum number of lines using counter-control unit

摘要

A circuit of the control and storage of switching signals exchanged between remote positions, especially for application in electronically controlled telephone exchanges between a multipurpose supervisory board and the board control unit, a counter-decoder unit in the board control unit supplies a clock signal to the integrated units serving as memory units and converters and also to an amplifier of the supervisory board through which the six circuits, which are controlled by six keys on the board can be interrogated over eighteen lines; a recognition unit monitors the state of engagement of the eighteen lines to ensure that simultaneous engagement of two lines can only be evaluated by one of the circuits if a key is actuated to select a figure; a keying blocking sequence can be programmed by a diode matrix to prevent the keying in of unwanted key data.