Adapter for interfacing a computer to a multichannel digital network, with port for a telephone

A data communication adapter for use with a computer system at a single subscriber's premise for interfacing between said computer system and a digital signal communication network, said network having plural lines, each line providing plural channels for data communication including at least two B channels and at least one D channel, each said B channel supporting transmission of digital signals representing computer data and digitized voice signals, said adapter at said subscriber's premises comprising:

• a local telephone port;
• connection means for connecting a telephone handset to said local telephone port;
• said connection means comprising means for translating electrical signals respectively received at said local telephone port and a said handset into signals respectively suitable for audible reproduction at said handset and transmission on said network;
• two network connection ports, said ports serving to connect said adapter to two separate ones of said plural lines;
• said two separate lines together providing at least four separate B channels and at least two separate D channels for communication;
• a time division switch circuit coupled to said computer system, said two network connection ports, and said local telephone port;
• said switch circuit providing time division connections:
• (1) between said two network connection ports for routing digital signals directly between one of said two B (channels on one of said two separate communication lines and either (i) one of said two B channels on said other of said two separate communication lines or (ii) said other of said two B channels on said one of said two separate lines without intervening handling of respective signals in said computer system;
• (2) between said local telephone port and one of said network connection ports for routing digitized voice signals between one of said two B channels on one of said two separate communication lines and said local telephone port without intervening handling of respective signals in said computer system;
• (3) between said two network connection ports, said computer system and said local telephone port for routing signals between (a) one of said two B channels on one of said two separate communication lines and said computer system in one direction and while concurrently routing signals in a direction opposite to said one direction between said one B channel on said one separate communication line and either (i) one of said two B channels on said other of said two separate communication lines, (ii) said other of said two B channels on said one of said two separate lines or (iii) said local telephone port and
• (4) between said two network connection ports and said computer system for routing digital signals between said two network connection ports and said computer system.