Abstract:
A modem connected to a telephone line and capable of preventing noise from being generating upon the modem being powered-on or reset includes a ring detector for receiving a ring signal associated with an incoming telephone call through the telephone line and converting the ring signal to a binary ring signal; a datapump for processing the incoming telephone call; a controller coupled to the datapump and responsive to the ring detector, for generating an off-hook signal upon the ring signal to be detected, the off-hook signal including a leading portion of a pulse type constituting noise; a noise eliminating circuit for eliminating the leading portion of a pulse type included in the off-hook signal; and a modem driver for driving the modem in response to the off-hook signal from the noise eliminating circuit to cause a remote computer to communicate with a local computer connected to the modem or to switch a calling telephone to communicate with a called telephone. By the use of the modem, an off-hook signal constituting noise can be eliminated, the noise occurring instantly upon the modem being powered-on or reset. Therefore, no noise is introduced into the telephone line while the telephone of one calling subscriber is connected to the telephone of a called subscriber.
Abstract:
A computer system provided with a cable manager capable of connecting or disconnecting a variety of peripheral devices to or from a computer of the computer system by a single operation thereof, includes: a single integrated connector connected to a computer of the computer system, a plurality of peripheral device ports connected to respective ports of the peripheral devices, the peripheral device ports having a variety of shapes, a LAN modular connector for connecting the computer to a LAN server, and a LAN client card connected to the LAN modular connector.
Abstract:
A computer conferencing system is provided with a transmission signal synchronization scheme. An Audio signal frame has a synchronization (sync) signal. The formatted audio including the sync signal is transmitted, together with the video signal frame and data signal frame, to the remote conferencing system via a communications network, such as a PSTN. The conferencing system is provided with a synchronization signal generator coupled to the compressed signal output of the audio board by way of a mixer. Further, the system includes a multiplexer/demultiplexer that mutiplexes/demultiplexes compressed and formatted audio/video/data generated by the audio board, video board, and host processor, respectively, with the communication board for transmission to and reception from the remote conferencing system. A synchronization control unit is coupled to data input lines of the multiplexer/demultiplexer for enabling/disabling addition of the sync signal to the audio signal frame, and for selecting a sync signal source according to the priority set by a software module.
Abstract:
A reset circuit of a modem which permits the exchange of digital data with a remote modem in a computer system having an external reset switch provided thereon for allowing a user to reset the modem. The reset circuit includes a decoder section for receiving information from the computer system and decoding the same information to generate a first reset signal; and a signal output section having a first input terminal coupled to receive occurrence of the first reset signal, and a second input terminal coupled to receive occurrence of a second reset signal generated from the computer system in response to either manual depression of the external reset switch or an execution of a designated program contained in the computer system, for combining occurrence of the first reset signal and the second reset signal to generate a modem reset signal to a reset portion of the modem for resetting operation of the modem.
Abstract:
A specially designed external reset circuit for a modem in a computer system includes an external reset switch provided on the computer system accessible to a user and operable to generate a manual reset signal in response to the user's manipulation of said external reset switch. A signal stability circuit is connected to the external reset switch, for stabilizing the manual reset signal and preventing occurrence of a sudden surge of voltage when the external reset switch is turned on and turned off. A signal combination circuit includes a first input terminal coupled to receive occurrence of the manual reset signal and a second input terminal coupled to receive occurrence of a computer reset signal generated from the computer system, for logically combining occurrence of the manual reset signal and the computer reset signal to generate a modem reset signal. And a modem control circuit including a modem having a reset terminal connected to the signal combination circuit, for resetting operation of the modem in response to reception of the modem reset signal.
Abstract:
A portable computer has a modem telephone line expansion system, and includes: modem circuitry coupled to the portable computer system; a line interface section for reducing a line voltage across a telephone line to a low voltage analog signal level; and a line switch provided between an output of the line interface section and an input of the modem circuitry, and an expansion port the line switch selecting one of the telephone lines leading from the output of the line interface and the expansion port to the line input of the modem circuitry in response to a control signal produced when the portable computer is coupled to a docking station. The line interface includes a transformer with its primary coil connected to the telephone line and of its secondary coil connected to selected terminals of the line switch. Further, an expansion system for use with the above-mentioned type portable computer has a telephone line input port for connecting to a telephone cable; and an extra line interface section provided near the telephone line input port for connecting the telephone line to a port to be coupled to the portable computer.
Abstract:
A modem system having a voice message function of generating voices corresponding to a calling tone, an answering tone and a series of handshake operations, in which one modem calls another modem, answers thereto, exchanges parameters and digital data between them and terminates a connection between them. The modem system comprises a modem circuit, and a voice message control apparatus for performing the voice message function. The voice message control apparatus has a detector for detecting the operation state of a modem, a storage section for storing the voice message corresponding to the operation states of the modem, a message output section for outputting a voice message stored in the storage section, and a controller for enabling the message output section to output the voice message according to the operation state of the modem detected by the detector.
Abstract:
A wireless data communication system using a microphone/headphone jack of a portable phone. The system may be constructed with a computer modem; a microphone jack and a headphone jack of a portable computer; a portable phone having said microphone/headphone jack; and an interface module which transmits signals by electrically connecting said computer modem and said microphone/headphone jack of said portable phone. A dedicated cable for interfacing the modem and the portable phone is unnecessary, a private protocol for wireless communication is unnecessary, and the private protocol does not need to be previously written into a random access memory when the data of the portable computer is transmitted/received by wireless using the portable phone. The interface module circuit between the computer modem and the portable phone is simplified, by using less cables, and an existing jack may be used for coupling the modem and the portable telephone.