The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 09, 1977
Filed:
Jun. 03, 1976
Michael L Ellis, San Diego, CA (US);
ICC, Inc., San Diego, CA (US);
Abstract
A bi-directional digital communication unit for requesting the performance of services by transmitting data to a central computer complex for purposes of processing the data to utilize it to initiate the performance of the requested services and for receiving data from the central computer complex for purposes of determining whether the request for the performed services was received and the performance of the requested services was initiated. Data is transmitted from the central computer to the communication unit on a carrier wave at a first low frequency F.sub.1 and data is transmitted from the communication unit to the central computer at a second low frequency F.sub.2. The data received by the system, on the carrier wave having frequency F.sub.1, is demodulated and applied to valid address check means to determine if the central computer has transmitted a valid address to the unit. A modem register provides a data word which identifies the services that are requested by the user and transmits this data word to a data shift register which, if the system has received a valid address from the central computer, transmits the data word to the central computer, on a carrier wave at frequency F.sub.2, to initiate the performance of the requested services. The system includes a receiver data register which, after a subsequent valid address by the central computer of the communication system, registers the receipt by the unit of a data word from the central computer signifying the receipt by the central computer of the request for services, and controls visual displays in the modem control code generator to visually inform the user of the receipt by the central computer of the data word generated by the modem control code generator and the initiation of the performance of the requested services. The system includes a master clock frequency divider and control logic for providing timing and logic pulses to synchronize the operation of the system and coordinate it with that of the central computer.