Telephone exchange with central control device - reading selector data from connection stores associated with sub-control devices

摘要

The centrally-controlled telephone exchange has the storage devices that store the stages of an existing connection via the switching matrix grouped together in a connection via the switching matrix grouped together in a connection storage area such that the subcontrol devices are assigned individually, i.e. not duplicated. After the path-finding storage assigned to the central control device has been cleared (correctly or incorrectly) the stored data needed for route finding are read from the connection stores assigned to the subcontrol devices by the central control device without deleting and written into the selector store. The advantage lies in reducing storage space by duplicating both the central control device and its associated storage devices but avoiding duplicating the stores associated with the subcontrol devices.