Digital key telephone connecting apparatus and method in a digital key telephone system

A method for connecting a first digital key telephone to a second digital key telephone in a digital key telephone system, comprising the steps of:

• designating said first digital key telephone directly connected to said digital key telephone system as a masterphone, and designating said second digital key telephone connectable to said first digital key telephone as a slavephone, said first and second digital key telephones being separated by a prescribed distance;
• and
• connecting transmission devices within said masterphone and said slavephone to each other via a connecting medium to enable said masterphone and said slavephone to mutually transmit data and voice signals, the connecting medium including a transmission line and a transformer connected to the slavephone through the transmission line;
• wherein the transmission devices comprise a first transmitter connected to data transmission and receiving terminals, a D channel clock terminal and an input/output control port of a microprocessor of said masterphone, said first transmitter including synchronizing signal terminals and a B channel clock terminal connected to a second transmitter of said masterphone.

A device for connecting a first digital key telephone to a second digital key telephone in a digital key telephone system, said device comprising:

• a first transmitter electrically connected to receive B channel data and synchronizing signals from a second transmitter installed within said first digital key telephone, and to receive D channel data from a microprocessor installed within said first digital key telephone;
• a transformer for connecting said device to said second digital key telephone via a transmission line;
• and
• means for connecting input and output terminals of said first transmitter to said transformer to connect said device to said second digital key telephone and enable electrical communication between said first digital key telephone and said second digital key telephone.

A method for connecting a first digital key telephone to a second digital key telephone in a digital key telephone system, comprising the steps of:

• designating said first digital key telephone directly connected to said digital key telephone system as a masterphone, and designating said second digital key telephone connectable to said first digital key telephone as a slavephone, said first and second digital key telephones being separated by a prescribed distance;
• and
• connecting transmission devices within said masterphone and said slavephone to each other via a connecting medium to enable said masterphone and said slavephone to mutually transmit data and voice signals, the connecting medium including a transmission line and a transformer connected to the slavephone through the transmission line;
• wherein the transmission devices comprise a first transmitter electrically connected to recieve B channel data and synchronizing signals from a second transmitter installed within said masterphone, and to receive D channel data from a microprocessor installed within said slavephone.

An apparatus for providing electrical communication between a first digital key telephone and a second digital key telephone in a digital key telephone system, said apparatus comprising:

• a first transmitter having a B channel clock port, a B channel receiving port, a B channel transmission port, a D channel clock port, a D channel receiving port, a D channel transmission port, a synchronization port, an input port and an output port,
• said B channel clock port electrically connected to a second transmitter installed within said first digital key telephone to receive B channel clock signals,
• said B channel receiving port electrically connected to said second transmitter through a first tri-state buffer to receive first B channel data from said first digital key telephone and transmit said first B channel data to said second digital key telephone via said output port,
• said B channel transmission port electrically connected to said second transmitter through a second tri-state buffer to transmit second B channel data received from said second digital key telephone via said input port to said first digital key telephone,
• said D channel clock port electrically connected to a microprocessor installed within said first digital key telephone to transmit D channel clock signals, and
• said D channel receiving port electrically connected to said microprocessor to receive first B channel data from said first digital key telephone and transmit said first B channel data to said second digital key telephone via said output port.