Network terminal apparatus
First Claim
1. An ISDN network terminal apparatus comprising:
- a U-interface circuit for coupling to an ISDN switchboard and for executing transmission/reception therewith using two B-channels of data and one D-channel of data;
an S-interface circuit for coupling to a terminal and for executing transmission/reception of data on said two B- and one D-channels said data exchange being carried out in accordance with a predetermined CCITT standardand wherein said U-interface circuit comprises;
U-interface transmission/reception circuit for executing activation and non-activation activities by exchanging data with said S-interface circuit,a hybrid circuit coupled to said U-interface transmission/reception circuit for converting 4-wire signals on the terminal side to 2-wire signals on the switchboard side and vice versa,a transformer for coupling said hybrid circuit to a jack switchboard,said jack for coupling said transformer to said switchboard, andan oscillator for providing a predetermined clock pulse signal to said U-interface transmission/reception circuit for synchronizing the operation thereof,and wherein said S-interface circuit comprises;
an S-interface transmission/reception circuit in said S-interface circuit for exchanging data with said U-interface circuit,an overvoltage protection circuit coupled via four wires to said S-interface transmission/reception circuit for protecting said S-interface transmission/reception circuit against voltages higher than a predetermined level which will damage the circuitry of the S-interface circuit,first and second transformers provided for transmission and reception of data and coupled to said S-interface transmission/reception circuit through said overvoltage protection circuit,a jack for physically coupling said first and second transformers to said terminal,and a selection switch coupled to said S-interface transmission/reception circuit for controlling whether point-to-point or point-to-multipoint terminal operation is desired.
4 Assignments
0 Petitions
Accused Products
Abstract
This invention relates to a network terminal apparatus in ISDN for connecting a two-wire U-interface on the switchboard side and a four-wire S-interface on the terminal side to each other. A network terminal apparatus disclosed for causing signals from the switchboard or the terminal to enable or disable the circuitries in the periphery of transmission/reception means of S- and U-interfaces, thus dispensing with use of a microprocessor and notifying the user of the status by LED display means. It comprise U-interface means connected to a switchboard for transmitting/receiving channel data 2B+D as a reference transmission rate, S-interface means connected to a terminal for transmitting/receiving channel data 2B+D, a status display for displaying activation status of the system, and electric supply means for supplying a regular and backup source, and reset means for performing a system resetting action.
12 Citations
6 Claims
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1. An ISDN network terminal apparatus comprising:
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a U-interface circuit for coupling to an ISDN switchboard and for executing transmission/reception therewith using two B-channels of data and one D-channel of data; an S-interface circuit for coupling to a terminal and for executing transmission/reception of data on said two B- and one D-channels said data exchange being carried out in accordance with a predetermined CCITT standard and wherein said U-interface circuit comprises; U-interface transmission/reception circuit for executing activation and non-activation activities by exchanging data with said S-interface circuit, a hybrid circuit coupled to said U-interface transmission/reception circuit for converting 4-wire signals on the terminal side to 2-wire signals on the switchboard side and vice versa, a transformer for coupling said hybrid circuit to a jack switchboard, said jack for coupling said transformer to said switchboard, and an oscillator for providing a predetermined clock pulse signal to said U-interface transmission/reception circuit for synchronizing the operation thereof, and wherein said S-interface circuit comprises; an S-interface transmission/reception circuit in said S-interface circuit for exchanging data with said U-interface circuit, an overvoltage protection circuit coupled via four wires to said S-interface transmission/reception circuit for protecting said S-interface transmission/reception circuit against voltages higher than a predetermined level which will damage the circuitry of the S-interface circuit, first and second transformers provided for transmission and reception of data and coupled to said S-interface transmission/reception circuit through said overvoltage protection circuit, a jack for physically coupling said first and second transformers to said terminal, and a selection switch coupled to said S-interface transmission/reception circuit for controlling whether point-to-point or point-to-multipoint terminal operation is desired. - View Dependent Claims (2, 3, 4, 5, 6)
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Specification