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:
Jan. 27, 1998
Filed:
Sep. 06, 1995
Yutaka Takahashi, Sendai, JP;
Toshihiro Ibuka, Sendai, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
A UART (Universal Asynchronous Receiver/Transmitter) is used to interface serial data signals, and is provided to associate with a micro-processor in a micro-processor unit. The micro-processor unit is required to save consumption of power, if employed in such devices as a handy terminal device or the like. The micro-processor unit that can save consumption of power includes a microprocessor having a core section, which performs an arithmetic operation, and a universal asynchronous receiver/transmitter section operatively connected to the core section of the micro-processor. The universal asynchronous receiver/transmitter has a first circuit for receiving an asynchronous serial data signal, which is composed of a start bit, a stop bit and data bits provided between the start and stop bits. The first circuit also detects the start bit. Also included in the universal asynchronous receiver/transmitter is a second circuit for setting a flag indicating that the asynchronous serial data signal is being received when the start bit is detected by the first. When the micro-processor detects that the flag is set, stops the supply of clocks to the core section in a sleep mode.