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:
Nov. 30, 1993
Filed:
Feb. 21, 1991
Kazuhiko Maruyama, Kasugai, JP;
Yosinori Tuzita, Owariasahi, JP;
Tomoyuki Yukawa, Owariasahi, JP;
Toru Saito, Yamato, JP;
Yutaka Kawakita, Yokohama, JP;
Hitachi, Ltd., Tokyo, JP;
Hitachi Communication System, Inc., Tokyo, JP;
Abstract
A communication control unit for integrated service digital network (ISDN) is disclosed. The ISDN communication control unit includes a data communication adapter for transmitting and receiving data to and from the ISDN and a voice adapter for transmitting and receiving voice data received from the ISDN, through the data communication adapter. The voice adapter includes a memory for storing voice data, a compression and expansion circuit for voice data, a temporary storage circuit for voice data, a monitor unit for voice data, a communication path change-over circuit for changing over a communication path between said temporary storage circuit, said monitor circuit and the ISDN, and a control unit for controlling these. A communication path is changed over by the communication path change-over circuit, to mutually transmit and receive voice data between the temporary storage circuit, the monitor circuit and the ISDN.