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:
May. 03, 1988
Filed:
Dec. 31, 1984
Applicant:
Inventors:
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G06F / ;
U.S. Cl.
CPC ...
364900 ;
Abstract
A master station and a plurality of slave stations are connected in multi-drop connection. A carrier wave on an upstream transmission line between the master station and the slave stations is demodulated and re-modulated in each slave station and always maintained to be on-state. Both the modulating and demodulating devices are performed by a MODEM following the protocol CCITT V.28, respectively. Each MODEM used is connected to the respective slave station by a signal line following the protocol EIAR3 232C.