Subscriber switch controller for controlling connections between a plurality of telephone subscriber lines and a pair of multitime-slot digital data buses

In a telephone system operating in time frames each consisting of a plurality of time slots having a first time slot rate, said system including a base switch connected to a plurality of multitime-slot buses for switching data between any of the time slots and including a subscriber switch connected to a plurality of local subscriber lines and to a pair of said plurality of buses for switching encoded data between said subscriber lines and time slots on said pair of buses specified by said base switch, said subscriber switch including a pair of subscriber switch controllers for enabling the switching of encoded data between said plurality of subscriber lines and said pair of buses, an arrangement wherein each of said controllers comprises:

• interface means responsive to control signals for switching first encoded data from said subscriber lines in specified time slots in one of said pair of buses and for switching second encoded data from one of said pair of buses to specified ones of said subscriber lines,
• processor means responsive to said time slots specified by said base switch for generating said control signals,
• said interface means including attenuation memory means for storing predetermined encoded data representing predetermined attenuation states and means connected to said receive data bus for addressing said attenuation memory means at locations corresponding to an attenuated value for switching said attenuated data to said subscriber lines.

In a telephone system operating in time frames each consisting of a plurality of time slots having a first time slot rate, said system including a base switch connected to a plurality of multitime-slot buses for switching data between any of the time slots and including a subscriber switch connected to a plurality of local subscriber lines and to a pair of said plurality of buses for switching encoded data between said subscriber lines and time slots on said pair of buses specified by said base switch, said subscriber switch including a pair of subscriber switch controllers for enabling switching of encoded data between said plurality of subscriber lines and said pair of buses, an arrangement wherein each of said controllers comprises:

• interface means responsive to control signals for switching first encoded data from said subscriber lines in specified time slots in one of said pair of buses and for switching second encoded data from one of said pair of buses to specified ones of said subscriber lines,
• processor means responsive to the time slots specified by said base switch for generating said control signals,
• said interface means including assignment memory means having a number of storage locations corresponding to said multitime-slot data buses for storing said control signals specifying the switching of said first encoded data to the specified time slots on said data buses, means for writing said control signals into said locations, and means for reading said control signals at said locations thereby providing enabling signals.

In a telephone system operating in time frames each consisting of a plurality of time slots, said system including a base switch connected to a plurality of multitime-slot buses for switching data between any of the time slots and including a subscriber switch connected to a plurality of local subscriber lines and to a pair of said buses for switching encoded data between said subscriber lines and time slots on said pair of buses specified by said base switch, said subscriber switch including a subscriber switch controller for enabling switching of encoded data between said plurality of subscriber lines and said pair of buses, an arrangement comprising:

• a receive multitime-slot data bus for carrying first encoded data from said pair of buses to said subscriber lines,
• a receive multitime-slot command bus for carrying control signals specifying switching of said first encoded data on said receive data bus to particular ones of said subscriber lines,
• a transmit multitime-slot data bus for carrying second encoded data from said subscriber lines to said pair of buses,
• a transmit multitime-slot command bus for carrying control signals specifying the switching of said second encoded data on said transmit data bus to time slots on said pair of buses specified by said base switch,
• interface means connected to each of said transmit and receive buses and to said pair of buses for switching said first and second encoded data between said subscriber lines and said pair of buses, and
• processor means for generating said control signals responsive to the time slots specified by said base switch.

In a telephone system operating in time frames each consisting of a plurality of time slots having a first time slot rate, a subscriber switch controller comprising:

• a receive multitime-slot data bus having a second time slot rate, faster than said first time slot rate, for carrying first encoded data from a pair of multitime-slot data buses to a plurality of subscriber lines,
• a receive multitime-slot command bus having said second time slot rate for carrying control signals specifying the switching of said first encoded data on said receive data bus to specified ones of said subscriber lines,
• a transmit multitime-slot data bus having said second time slot rate for carrying second encoded data from said subscriber lines to said pair of buses,
• a transmit multitime-slot command bus having said second time slot rate for carrying control signals specifying the switching of said second encoded data on said transmit data bus to said time slots on said pair of buses,
• interface means connected to each of said transmit and receive buses and to said pair of buses and responsive to control signals for switching said second encoded data from said subscriber lines to specified time slots on said pair of buses, and for switching said first encoded data from said pair of buses to specified ones of said subscriber lines, and
• processor means for generating said control signals.