1
Raouf Y Halim, Randy D Nash: High performance sigma delta based analog modem front end. Hayes Microcomputer Products, Jones Askew & Lunsford, November 20, 1990: US04972436 (145 worldwide citation)

An improved analog front end circuit for a high performance modem comprising an oversampling sigma delta modulator analog-to-digital converter which employs a novel four phase clocked MOSFET switched capacitor integrator. The integrator is switched in a manner as to eliminate signal dependent charge ...


2
Ashok Dittakavi, Robert L Richards, Raouf Halim: Modem with call waiting. Hayes Microcomputer Products, Jones Askew & Lunsford, July 25, 1989: US04852151 (125 worldwide citation)

A modem is adapted to accommodate a call waiting feature so that a user can select to continue an ongoing call or accept an incoming call. The modem detects a call waiting signal and generates a call waiting message. Where a call waiting signal is preceded by a loss of carrier, the modem detects the ...


3
John A Copeland III: Adaptive data compression method and apparatus. Hayes Microcomputer Products, Jones Askew & Lunsford, August 29, 1989: US04862167 (118 worldwide citation)

A method and apparatus for compressing data, particularly useful in a modem. The preferred method is implemented in a microprocessor within a modem, and dynamically adapts to changing data statistics. Parallel encoding and decoding tables are provided at the encoder and the decoder, and are updated ...


4
Paul E McGlynn, Randy D Nash: Feature negotiation protocol for a synchronous modem. Hayes Microcomputer Products, Jones Askew & Lunsford, August 28, 1990: US04953210 (96 worldwide citation)

A method for feature negotiations between two synchronous modems. To engage in negotiations a modem must be configured to support synchronous operation, a data transfer rate of at least 4800 bits per second, and at least one non-default feature. After the orginating modem and the answering modem hav ...


5
Alan D Clark: Adjusting encoding table size and memory allocation for data compression in response to input data. Hayes Microcomputer Products, Jones & Askew, May 6, 1997: US05627533 (64 worldwide citation)

A real-time method for improving data compression. The correlation between data characters being provided a modem (10) is determined. Two measures are used to determine the correlation between data characters: the shape of tree(s) (6) in encoding table (16) and the compression ratio (96). Once the c ...


6
Paul E McGlynn, Randy D Nash: Feature negotiation protocol and dynamically adjustable retraining sequence for a high speed half duplex modem. Hayes Microcomputer Products, Jones Askew & Lunsford, February 27, 1990: US04905282 (52 worldwide citation)

A feature negotiation protocol for synchronous operation and a dynamically adjustable retraining sequence. An originating modem, after completing conventional or standard handshaking sequences, sends a list of desired features to an answering modem. The answering modem either concurs with the desire ...


7
Jay P Duncanson, Mark R Murray: Synchronous/asynchronous modem. Hayes Microcomputer Products, Jones Askew & Lunsford, October 13, 1987: US04700358 (45 worldwide citation)

An improved modem is described which can selectably operate in a synchronous communications mode, an asynchronous data mode, and an asynchronous command mode. A processor 47 controls the operation of the modem, adds starting and ending flags and frame check sequences to transmitted data, searches fo ...


8
Vikram Bhargava, Donald A Muntner, Ronald H Cone, James R Heberling, Mark E Hicks, Samuel W Harris, David A Kutilek, Joseph A Duvivier: Apparatus for rack mounting multiple circuit boards. Hayes Microcomputer Products, Jones Askew & Lunsford, March 31, 1992: US05101320 (45 worldwide citation)

An improved rack assembly is provided which includes an improved configuration for mounting multiple enclosed circuit boards. The rack assembly includes improvements in heat sinking power supplies incorporated within the assembly, relative adjustability of various elements of the rack after assembly ...


9
Douglas R Kraul, Stuart A Cox: Method and apparatus for implementing an escape sequence. Hayes Microcomputer Products, Jones Askew & Lunsford, May 15, 1990: US04926448 (43 worldwide citation)

A multi-port message buffer which is responsive to an escape sequence. A control unit controls whether the message buffer is in a transparent mode or a command mode with respect to a particular port. The control unit monitors a data port for the escape sequence and, if the escape sequence is detecte ...


10
Taruna Tjahjadi, German E Correa, Matthew F Easley, John N Martin, Charles H McCorvey Jr, Randy D Nash, Cynthia A Panella, Michael L Rubinstein, Martin H Sauser Jr, David F Strawn, George R Thomas: High speed half duplex modem with fast turnaround protocol. Hayes Microcomputer Products, Jones Askew & Lunsford, January 16, 1990: US04894847 (40 worldwide citation)

A modem with improved signal processing and handshaking capabilities as described. Two digital signal processors are used to perform independent, concurrent operations so that a faster execution rate is obtained and more precise calculations are made possible. The modem also uses an improved handsha ...